hybridfree/eevblog-posts huggingface dataset:
I2C Bus usage - Page 1
Forum section: electronics / projects

author: THORs_Hand
author_rank: Contributor
timestamp: January 23, 2019, 12:21:01 am
content: Hello!I'm gathering the required parts to slap together a custom tablet PC,I'm planning to combine the guts of an ASUS X55A laptop (Intel Celeron 1000M modelhttps://www.asus.com/Laptops/X55A/) with the display and touchscreen of an HP Envy X2 11g-series tablet, now since the tablet is useless (no, really, it barely handles Windows) and the X55A has no display and it doesn't worth repairing, i thought why not combine them into a tablet, since i need one.My problem so far is the touchscreen, the display it's standard LVDS, but the touch panel it's I2C, as far as i remember (since i have no way of checking again) the X55A doesn't have any devices (in device manager) that are connected to the I2C bus;I read online that i could either connect it to the SMBus, or DDC bus, but i don't know if it would work, i don't really have a way to test it.In it's service manual (http://h10032.www1.hp.com/ctg/Manual/c03581901) at page 57/87 you can see the board, i found pictures online of the board (i didn't open the tablet yet out of fear of loosing something important like i always do) but i couldn't find them again to attach them here, these boards seem rare.On the flat flex connecting it to the main PCB there are 8 pins, and a BGA chip on the connector board i can't see the model number on.How can i connect that panel to the laptop?Does the X55A has any I2C bus? or can anyone help me with a schematic of the motherboard? i can't find it anywhere.P.S. I imagine that converting the I2C to USB will make the driver useless, it working with it's driver it's critical since it has the display mapping.Thank you in advance

author: IMI4tth3w
author_rank: Contributor
timestamp: January 23, 2019, 01:08:21 am
content: from my limited experience with touch screens, they usually have multiple options for connectivity. Can you find the main touch IC so we can look up the datasheet? There might be a USB output hidden in there somewhere.

author: THORs_Hand
author_rank: Contributor
timestamp: January 23, 2019, 10:19:03 am
content: Hey,I opened it up (breaking it's glass)The mystery chip is : AtMel MXT1664S-CUCouldn't find it's datasheet
I2C clock low level=1.4V - Page 1
Forum section: electronics / projects

author: Emil
author_rank: Regular Contributor
timestamp: February 14, 2020, 01:11:25 pm
content: I have an I2C bus with an ESP32 master and two devices (TMP1075 and MM7660).SCL has a high level of ~3.3V and a low level of ~1.4V. (SDA is normal at ~3.3V high and ~0.1V low.)I use 4.7K pull-ups on both SCL and SDA. I have also tried removing the resistors and using only the internal pull-ups of the ESP32, with the same result.Measuring SCL with CH1 gives the same result, so not a problem with the probe or channel settings.Any suggestions as to what may be causing this?Code:i2c_config_t conf = {0};conf.mode = I2C_MODE_MASTER;conf.sda_io_num = 21;conf.sda_pullup_en = GPIO_PULLUP_DISABLE;conf.scl_io_num = 22;conf.scl_pullup_en = GPIO_PULLUP_DISABLE;conf.master.clk_speed = 100000;i2c_param_config(i2c_master_port, &conf);i2c_driver_install(i2c_master_port, conf.mode, 0, 0, 0);

author: magic
author_rank: Super Contributor
timestamp: February 14, 2020, 03:27:07 pm
content: Disconnect each device and see what happens?
I2C data lines short - Page 1
Forum section: electronics / projects

author: greencardigan
author_rank: Contributor
timestamp: August 14, 2021, 07:01:54 am
content: Hi,I've just finished building a batch of 6 boards and one has a issue with the I2C lines. There seems to be a short between the data lines and ground. The resistance between either data line and ground is 0.3 ohms. Resistance across my 4.7K data line pull up resistors is 2.36K (i.e. they're in parallel).I can't see any issue with the board or soldering, so I'm assuming there is an issue with one of the three ICs connected to the I2C bus.Is it possible to identify which IC is causing the short before removing them?Schematic pdf for the board is here.https://github.com/greencardigan/TC4-shield/blob/master/hardware/TC4/TC4%20V600/tc4-controller-0600-sch.pdfEdit: I've already tried reflowing the pins on the three ICs.

author: Ian.M
author_rank: Super Contributor
timestamp: August 14, 2021, 08:03:48 am
content: Two of the chips are SOICs, so you can easily lift individual pins. Remove as much solder as possible with desolder braid then lift the pin with a mounted needle while heating it. I always like to slip a sliver of Kapton sheet or waxed paper under the pin to confirm there aren't any solder whiskers maintaining contact so I don't have to lift the pin high enough for visual inspection of the gap.Don't forget to bend the pin back down before resoldering it after you are done testing.

author: greencardigan
author_rank: Contributor
timestamp: August 15, 2021, 05:54:22 am
content: Thanks. I lifted the data pins on both SOICs without any luck. Then removed the smaller IC, I2C headers and pull up resistors. Still no luck.Finally removed the two SOICs completely and found something underneath the EEPROM. It was easily scratched away with tweezers but was probably just a solder bridge up under the chip.Resoldered all the parts and it's back in action. Only needed to replace the MCP9800.
I2C design consideration for mulitple slaves and long-term reliability - Page 1
Forum section: electronics / projects

author: Johannsen
author_rank: Regular Contributor
timestamp: January 15, 2021, 01:27:54 pm
content: Hi,I need a RTC AB1805, an EEPROM and a I2C SSD1306 OLED connected to a MCU SAMD21. I packed everything together on a first prototype board and it's working. However I read several times of I2C being not that reliable. OLED and EEPROM I only need when the MCU is awake. Besides the OLED all slaves are directly connected to 3v3. My Oled is connected to 3v3 via a high-side switch that can be turned off during sleep. The RTC needs to be capable of interrupting the MCU and awake it. All 3 slaves are on a single common I2C bus at the moment.Would it be better to spend a single only I2C line for the RTC? Also I'm asking myself what's happen when I switch off the VCC of the OLED. How does it affect the common I2C line. At the moment it's working as it is but in terms of longtime run I'm not sure.(also in terms of power consumption)
I2C Display freezing after power ON - Page 1
Forum section: electronics / projects

author: anishkgt
author_rank: Frequent Contributor
timestamp: August 15, 2018, 10:25:37 am
content: I have an 16x2 lcd which works at first power on but does not update latter. I did not have pullup resistors for the SDA and SCL when i ordered the PCB. It worked without them as well but often strange characters would scroll, now all i did was add 10k pullup resistors on the SDA and SCL pins.i replaced the PCF interface IC now the screen is completely blank as in solid blocks instead of the characters. It is not contrast either. Otherwise the Atmega IC works with the code.

author: HB9EVI
author_rank: Frequent Contributor
timestamp: August 15, 2018, 01:20:19 pm
content: I2C requires pullups, since it's driven by an open drain circuit.the PCF8574 is found in many lcd backpacks, works ok, but requires the right bus speed and the lcd requires the right timing, which is no so easy to achieve, if you write your lcd lib from the scratchI bet it's a speed or timing issue. some more information about the project/code would be helpful.

author: anishkgt
author_rank: Frequent Contributor
timestamp: August 15, 2018, 03:26:35 pm
content: About the pull-up resistors do they need to be near microcontroller or the interface IC ? The interface IC is on a another pcb connected by a 2x5 connector using a flat ribbon cable of length 15cm.Www.Georgehobby.wordpress.comEquipments: DSO104z, Hakko FX888D, Brymen BM869s

author: lamello
author_rank: Contributor
timestamp: August 15, 2018, 05:45:49 pm
content: The pull-up resisters don't have to be near the uC or interface IC. I use 4k7 or 3k3 resistors for the pull-ups.If you have a scope, you could check if a high on the SDA and SCL is nearly 5Volt. If not, lower the resister value of the pull-up resistors.Just my 2ct.Greetings,Lamello

author: anishkgt
author_rank: Frequent Contributor
timestamp: August 15, 2018, 07:28:22 pm
content: The 10k resistors where taken from the Arduino schematic. never knew why they were there for but now i do.Not sure what am looking at the scope but yes they SDA SCL are at 5v

author: lamello
author_rank: Contributor
timestamp: August 15, 2018, 09:38:32 pm
content: You have changed the PCF8574. Is the new chip really a PCF8574 or is it a PCF8574A?The functionality of those chips are the same, with one exception. They have a different i2c address.PCF8574 i2c address 0x27PCF8574A i2c address 0x3FGreetingslamello
I2C level shifter for a breakout board - Page 1
Forum section: electronics / projects

author: Richard_L
author_rank: Contributor
timestamp: March 10, 2014, 04:45:47 pm
content: Hello all,I'm looking to create a breakout board for a 3V3-only I2C sensor. I'd like to be able to use the sensor with both 5V and 3V3 microcontrollers and have been reading the Philips app note AN97055www.adafruit.com/datasheets/an97055.pdf?(warning, pdf) which details a bi-directional MOSFET-based level shifting circuit.The circuit as given in the data sheet is below, with the pull-up resistors on each side of the level shifting MOSFETs connected to different supplies.Now in order to use the circuit on a breakout board and allow use with either 5V or 3V3 micros, would the following be correct? - The principal deviation from the app note being that all pull-up resistors are permanently tied to 3V3 regardless of whether the "high-side" logic levels are indeed higher at 5V or the same at 3V3. (The headers on the breakout board are the breaks & text in the green outline on the right hand side of the diagram.)Please excuse the melding of circuit diagram and block diagram, I'm still in the planning stage for this project and haven't fired up KICAD yet,thanks,Richard

author: linux-works
author_rank: Super Contributor
timestamp: March 10, 2014, 10:11:44 pm
content: that won't work (well). it might work but its not correct.I built one using that schematic (funny proto shown here):its ok to laugh. it makes me laugh and I built the damned thingall I had on hand was the tiny smd mosfets and so I did the best I could to hand/air wire them.but anyway, you have to tie the pullups to the LOCAL Vcc, be it 5v on one side or 3.3 on the other.the general idea is that it sits at the 'right' high level and gets pulled down on 0's. a zero is a zero to all logic (more or less) but a high could be 5v or 3v.so its best to not try to redefine what 'high' is for the A or B side or your circuit.(btw, this build of mine certainly redefines what it means to use GLUE LOGIC. hahahaha)

author: nctnico
author_rank: Super Contributor
timestamp: March 10, 2014, 11:36:04 pm
content: I'd use a chip made for this purpose. Much easier.
I2C Level Shifters, buffers, Pull-ups, etc - Page 1
Forum section: electronics / projects

author: Pack34
author_rank: Frequent Contributor
timestamp: September 14, 2018, 06:31:16 pm
content: I'm working on a board that has a single I2C bus that's going off-board to six sensors that could be two to three feet from the PCB. Because of this I'm looking at buffering the I2C bus going to each off-board sensor with a buffer to isolate each bus.One big question is, since I'm pulling the bus HIGH before the buffer and next to the MCU, do I need pull-ups on the sensor side of the buffer? I would think the answer would be "no" since the buffer is bi-directional and the input should mirror the output.I'm looking at using the part below since it incorporates ESD protection and allows both sides of the level shifter to be the same voltage level.https://datasheets.maximintegrated.com/en/ds/MAX3372E-MAX3393E.pdfThoughts?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: September 14, 2018, 08:29:01 pm
content: Wow, I finally found a reference...https://incompliancemag.com/article/a-brief-history-of-electrostatic-discharge-testing-of-electronic-products/in case anyone else was wondering, IEC-1000 was actually a standard, so it's  not a typo. Question then remains, why is Maxim sticking to a 23-year-old standard?(Yes, this has been bothering me for some time.)Offhand, I don't see how a bidirectional buffer is supposed to work. I guess the logic-high isn't maintained, and logic-low is transmitted. I suppose the TRISTATE function will have to be active, in which case yes, you'll need pull-ups on both sides (so, add pull-ups on the sensor side).Tim

author: maginnovision
author_rank: Super Contributor
timestamp: September 14, 2018, 09:03:39 pm
content: Typically you do not want pull ups on both sides, but I haven't checked the datasheet. On TI bidirectional txs/txb auto level translators they have alot of data.

author: bson
author_rank: Unknown
timestamp: September 14, 2018, 11:12:58 pm
content: How about an NMOSFET?Actually, I'm curious about it so will put together a small board to test it out...Done and ordered (with JLPCB - $2 for the PCBs and $20 for DHL shipping). Should have them in 4-5 days.

author: texaspyro
author_rank: Super Contributor
timestamp: September 15, 2018, 03:12:22 am
content: Check out the PCA9306 chip...
I2C master IC cheaper than a microcontroller to configure I2C slaves - Page 1
Forum section: electronics / projects

author: ddavidebor
author_rank: Super Contributor
timestamp: August 29, 2022, 12:07:53 pm
content: Hi guys,Does anyone know if the following IC exists ?A simple i2c master, either with embedded memory or supporting external memory, that sends a series of commands to a I2C slave. Basically configuring the IC at power-on.The reason being sometimes you don’t really need a whole microcontroller for it.I figure someone must make it and I just don’t know how it’s called.I’m sure plenty of MCUs could be used to do the job.

author: Ian.M
author_rank: Super Contributor
timestamp: August 29, 2022, 12:18:28 pm
content: *IF* anyone made such an IC, it would most likely consist of a custom programmed small MCU, from an obscure small niche manufacturer, sold at at least a x10 markup, and the programming tool for it would be ridiculously expensive! The number of possible command sequences and the need for programmable delays, and possibly also decision making capability, and signaling status to the rest of the system almost demands that a general solution would run a scripting language, and hence run on a MCU.Get over your 'need a MCU' related hang-ups and use any small low pin-count MCU you are reasonably familiar with, running your own initialization code.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: August 29, 2022, 12:30:56 pm
content: Literally any MCU could do it, e.g. PIC10F200, and if you don't want the hassle of programming it in production, you can order the preprogrammed for a few cents more.If volume cost-sensitive, any of the cheap Chinese MCUs would do it once you've got the toochain working.

author: rstofer
author_rank: Super Contributor
timestamp: August 30, 2022, 12:02:59 am
content: I've been retired for a very long time and nobody pays me anything. Nevertheless, when it comes to decision making I price my time at $100/hr. It clears the mind...I would develop the project with an Arduino board that has a removable DIP chip. Sure, it's overkill but that's going to depend on volume. The Non-Recurring Engineering (NRE) cost is going to balance with the production cost times the number of units. NRE time isn't cheap! After I get it working, I could port the code to an even smaller chip.If the ATmega328 is adequate, the job is simple and can probably be done in an hour or so. Good luck assembling anything for 1 hour of NRE.

author: dobsonr741
author_rank: Frequent Contributor
timestamp: August 31, 2022, 12:45:20 am
content: My goto part for this kind of work is ATtiny85. Developing with the Arduino IDE, using another Arduino to program the 85. Piece of cake and simple development process.

author: pcprogrammer
author_rank: Super Contributor
timestamp: August 31, 2022, 05:52:28 am
content: Here is a nice example project with a ATtiny85 to have it include USB as well.https://github.com/harbaum/I2C-Tiny-USBFar quicker to use one of these then to search for a dedicated IC like you described. Do like others advised, look into a MCU.
I2C parts for audio applications - Page 1
Forum section: electronics / projects

author: qpit3a
author_rank: Contributor
timestamp: September 11, 2013, 09:52:10 pm
content: I am interested in controlling the input selection and volume of an audio amplifier from an embedded controller. Wondering what sort of parts are suitable and reasonably cheap and easy to use. Note: I am using OPA2134 opamps in the pre-amp which have distortion: 0.00008%, and low noise so I wouldn't want to degrade that.Thanks for any help.

author: free_electron
author_rank: Super Contributor
timestamp: September 12, 2013, 01:29:33 am
content: ST has a bunch. TDA family. including input multiplexer, tone and volume control.

author: tszaboo
author_rank: Super Contributor
timestamp: September 13, 2013, 09:27:55 am
content: There are also the famous PGA2310/20 which is SPI, not I2C, but they work.

author: dannyf
author_rank: Super Contributor
timestamp: September 13, 2013, 10:39:36 am
content: QuoteNone of that matters much for audio applications.If you want to switch audio, you need to look for a particular feature.
I2C programming datasheet for SiI9293 HDMI receiver? - Page 1
Forum section: electronics / projects

author: Yansi
author_rank: Super Contributor
timestamp: January 12, 2020, 03:34:15 pm
content: Hello,got interested in this cheap HDMI receiver: Silicon Image SiI9293. But I fail to find an I2C programming datasheet for it.I have only the "main" datasheet, that does not contain any detailed info about the I2C interface and device configuration:https://datasheet.lcsc.com/szlcsc/1903061001_Lattice-SII9293CNUC_C369568.pdfDoes anyone have that document or know where to locate it?Thanks,Y.//EDIT: The document I am looking for seems to have a "SiI-PR-1066" reference. My google-fu seems weak today.

author: amyk
author_rank: Super Contributor
timestamp: January 12, 2020, 08:36:10 pm
content: csdn.net appears to have a copy but there's some form of registration/points download system on that site, maybe someone else can get it for you.

author: Yansi
author_rank: Super Contributor
timestamp: January 12, 2020, 08:51:25 pm
content: Yup, it is somehow listed there, but no way for me to download.https://download.csdn.net/download/ys_slj_1314/11648965//EDIT: CSDN stands for Chinese Software Developer Network. Interesting. Hopefully someone with access can send me a copy. Thx!

author: 7A2636OvuxwY
author_rank: Newbie
timestamp: November 16, 2022, 01:44:06 am
content: Did you ever manage to get this? Something that may help is thishttps://github.com/tomverbeure/color3/blob/master/bringup/sw/bringup/sii9233.c
I2C RGB light sensor that supports at least 6 configurable device addresses - Page 1
Forum section: electronics / projects

author: Psi
author_rank: Super Contributor
timestamp: March 21, 2024, 10:57:08 pm
content: Has anyone seen a I2C RGB light sensor where its i2c address can be configured with 3 of it's i/o pins?I want to put 6x SMT i2C light sensors on a little PCB in a row as part of a test jig to verify the 6 LED on the DUT are working and are the right color, which means all need different i2C addresses. I've been through looking at RGB light sensors datasheet but none had reconfigurable addresses for operation on the same bus.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 21, 2024, 11:25:48 pm
content: How about routing all LEDs with an optical fibre or light guide into one sensor and lighting one at a time?

author: PCB.Wiz
author_rank: Super Contributor
timestamp: March 21, 2024, 11:57:26 pm
content: The OPT4060 shows 4 address choices, and you could try the swapped SCL/SDA trick to double the parts on a i2c bus ?

author: MarkT
author_rank: Frequent Contributor
timestamp: March 23, 2024, 09:42:27 am
content: Not heard of that trick - does it always work?

author: fchk
author_rank: Frequent Contributor
timestamp: March 23, 2024, 09:52:49 am
content: Quote from: Psi on March 21, 2024, 10:57:08 pmUse a PCA9547 I2C Multiplexer. This splits out one I2C bus into eight subbusses where only one is active at a time. This allow you to have 8 devices with the same address - each on a single subbus. Selecting a subbus is also done by I2C, so no extra IOs are needed.https://www.nxp.com/docs/en/data-sheet/PCA9547.pdf

author: Psi
author_rank: Super Contributor
timestamp: March 23, 2024, 01:35:02 pm
content: Quote from: mikeselectricstuff on March 21, 2024, 11:25:48 pmThinking outside the box. I like it.Quote from: fchk on March 23, 2024, 09:52:49 amCool, i might use that
I2C RTC for sun tracking software - Page 1
Forum section: electronics / projects

author: eneuro
author_rank: Super Contributor
timestamp: March 30, 2015, 12:20:05 pm
content: Hello,Need to ugrade my sun stracking software for smaller SMD version and looking for I2C RTC clock.I will have soon in my hands this <$1PCF8563tRTC for testing.Expected operating temperature range -20*C .. 40*C.It looks like it has builtin oscilator, is small SO8 package and probably I will test it in my custom watch first to ensure it works as expected on daily basis.Time accuracy is not critical in sun tracking software, while as an option those units will have additional GPS module, so time reference can be taken from GPS and synchronize RTC clock, but if for some reason GPS data will not be available (Sun storm destoys GPS systemor GPS jammed ) RTC will be used to cross verify those two sensors time reading and if too much difference warning condition for sun tracker softwareAny issues with this PCF8563 I2C RTC? Anyone experienced any problems or maybe are there some traps?

author: dannyf
author_rank: Super Contributor
timestamp: March 30, 2015, 03:33:04 pm
content: QuoteLooks can be deceiving.

author: PeterFW
author_rank: Frequent Contributor
timestamp: March 30, 2015, 03:51:34 pm
content: Quote from: eneuro on March 30, 2015, 12:20:05 pmI am no expert, but you might run intro trouble with the accuracy on this temperature range, depending on how much you need.But if you sync every hour there might be no problem at all.I am using a maxim RTC with integrated temperature compensation.The DS3231 is not that expensive:http://www.maximintegrated.com/en/products/digital/real-time-clocks/DS3231.html

author: eneuro
author_rank: Super Contributor
timestamp: March 30, 2015, 06:16:20 pm
content: Quote from: eneuro on March 30, 2015, 03:51:34 pmYep, here are some hints from PCF8563t datasheet, but hopefully atomic clock not needed to be acurate 1 sun deg within a day or even month without GPS reference timeUPS: deleted my previous message by accident, but everybody knows that sun makes around 1 deg in 4 minutes

author: PeterFW
author_rank: Frequent Contributor
timestamp: March 30, 2015, 06:46:28 pm
content: I just realised... my apologies.The typical RTC is not compatible with flywheel batteries, due to the reversed lepton flow.
I2C splitter with western-ish connectors - Page 1
Forum section: electronics / projects

author: Krotow
author_rank: Regular Contributor
timestamp: March 13, 2025, 11:16:35 am
content: A question for people who use several I2C devices connected by cables and bus splitters in commercial projects where some devices might be affected by slight vibration too. Which connectors you are using? JST-something or something else? I would like to stop on connector which is1) Have western-ish descent, but manufactured also outside US.2) Available also in reputable shops like Mouser or Digikey.3) Are common enough to not worry about them disappearing from the only store that sells them.I will explain, why. There are a ton of random connectors who would fit the purpose. But several of those who are small and convenient enough like JST-GH are available only through Chinese retailers like AliExpress or from Amazon Chinese sellers. Finding them in western retailer shops is near to impossible. When you need to produce few hundreds of items, you don't want to become hit by supply shortage in situation when either some orange moron will throw another tantrum or Chinese sources (who often aren't legit enough for legal production) disappear due to another trade (or even real) war or simply because some guy sold his stock and vanished.Update: In general - which 4-pin connectors EE folk nowadays prefer to use for I2C, CAN and LIN internally inside devices.

author: thm_w
author_rank: Super Contributor
timestamp: March 13, 2025, 11:15:45 pm
content: You can look through the JST catalog:https://www.jst-mfg.com/product/index.php?type=2&key=11&page=1Maybe SM or HMhttps://www.jst-mfg.com/product/index.php?series=238https://www.jst-mfg.com/product/index.php?series=109SM is commonly usedhttps://www.mattmillman.com/info/crimpconnectors/common-jst-connector-types/GH is available on digikey no?

author: Kharn_the_Betrayer
author_rank: Contributor
timestamp: March 14, 2025, 07:43:32 pm
content: I'm personally a fan of the JST PA series. If you're worried about supply, another manufacturer to look into would be Molex, they're American-owned afaik.Something like this maybe (https://www.digikey.com/en/products/detail/molex/0355070400/403470)?
I2C to BQ 2024 with Bus Pirate. - Page 1
Forum section: electronics / projects

author: vasonline
author_rank: Contributor
timestamp: July 30, 2016, 06:05:05 pm
content: Hi,I am working with a old notebook battery.With the "Bus Pirate" I have made a connection with I²C to the BQ 2084Datasheet:http://www.ti.com/lit/gpn/bq2084I can communicate with it:Code:I2C>(1)Searching I2C address space. Found devices at:0x16(0x0B W) 0x17(0x0B R)I2C>I can read some interesting values like Cell Voltage1:Code:I2C>[0x16 0x3f [0x17 r]I2C START BITWRITE: 0x16 ACKWRITE: 0x3F ACKI2C START BITWRITE: 0x17 ACKREAD: 0x9DNACKI2C STOP BITAnd Cell 2 (and so on)Code:I2C>[0x16 0x3e [0x17 r]I2C START BITWRITE: 0x16 ACKWRITE: 0x3E ACKI2C START BITWRITE: 0x17 ACKREAD: 0x99NACKI2C STOP BITI2C>But I do not know how do you unseal them?They say write 0x2084 and 0x7A43 to register 0x00How do can I do that?Like This Below?I am a total newbie when it comes to writing I³C commands...I have broken down 2084 in 0x20 and 0x84. But is this right?Many thanks for any help or suggestionsCode:I2C>[ 0x16 0x00 0x20 0x84 ]I2C START BITWRITE: 0x16 ACKWRITE: 0x00 ACKWRITE: 0x20 ACKWRITE: 0x84 ACKI2C STOP BITI2C>[ 0x16 0x00 0x7a 0x43 ]I2C START BITWRITE: 0x16 ACKWRITE: 0x00 ACKWRITE: 0x7A ACKWRITE: 0x43 ACKI2C STOP BITBelow is a picture of the hardware.
I2C to SPI bridge - Page 1
Forum section: electronics / projects

author: kuon
author_rank: Regular Contributor
timestamp: March 10, 2021, 05:43:15 pm
content: I am making a new design and used the SC18IS602BIPW/S8HP I2C to SPI bridge, but I realize this product is being phased out.Do you know any alternative? I can't find any. I could add another micro controller, but this means another firmware, more tests....

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 10, 2021, 07:11:12 pm
content: Those are pretty rare these days unfortunately.One option would of course be to design your own, either using a MCU as you said, or a small FPGA.Lattice actually has a ready-to-use solution that is free to use AFAIK:https://www.latticesemi.com/Search.aspx?q=RD1172it comes with source code and was designed for iCE40 FPGAs, but should also be easy to port other devices. That said, iCE40 are relatively cheap and for this you would only need for instance an iCE40LP1K (the doc says the whole design takes ~700 LUTs) which is about $3.

author: kuon
author_rank: Regular Contributor
timestamp: March 10, 2021, 08:14:45 pm
content: I have no experience with FPGA, but I worked plenty with ATMega chips. I guess I could add one, but it would require a firmware and programming pins.

author: kuon
author_rank: Regular Contributor
timestamp: March 17, 2021, 09:10:03 pm
content: Actually as I already use ARM for main MCU, I used an STM32 chip, one of the smallest one in ultra low power. Works fine with a very minimal firmware I wrote.

author: rej
author_rank: Contributor
timestamp: March 18, 2021, 11:36:38 am
content: From where do you know, that it is phased out? On the nxp website it is labeled as active.

author: mattselectronics
author_rank: Contributor
timestamp: March 19, 2021, 12:27:25 am
content: Sometimes there are new revisions of long running products which have slightly different partnumbers.Sites like mouser or digikey sometimes find you the old numbers first, which may look like the part is obsolete, but only the old rev is.

author: kuon
author_rank: Regular Contributor
timestamp: March 19, 2021, 08:14:53 pm
content: Quote from: rej on March 18, 2021, 11:36:38 amI found this notehttps://media.digikey.com/pdf/PCNs/NXP/201708035I.pdfabout all /S8 parts being discontinued around 2024.But anyway, having a small low power MCU is actually better for my application. Because I can interrogate the ADC via SPI with a low power MCU and wake up the main MCU less often. This result in lower power use. I'll have to load a firmware, but actually it shouldn't be a problem.

author: tszaboo
author_rank: Super Contributor
timestamp: March 19, 2021, 09:20:23 pm
content: I believe NXP makes these sort of chips. I've only encountered these chips once, and the first thing I did was redesigning the product so it is not needed anymore.

author: kuon
author_rank: Regular Contributor
timestamp: March 20, 2021, 12:27:45 am
content: Yeah, when I realized I was hitting a special "niche" I realized it was better to move to something more "mainstream".
I2C traces layout - Page 1
Forum section: electronics / projects

author: crgarcia
author_rank: Regular Contributor
timestamp: February 28, 2022, 10:15:21 pm
content: I am supper beginner and (unfortunately) self-taught in electronicsI am building my first PCB project with an ESP32 and I am planning to add an Temp I2C sensor to it.I was trying to understand what are the requirements of I2C, but I do not fully understand them. That brings me some questions:* Can I2C traces go under other components in the same layer (resistors, ESP32)"* Do they have any requirements on track width* I understand that they don't need to be routed as differential pairs. In my case they have 21mm and 24mm long. Do I need to match them?* Do I need a ground trace in between them?* Is there anything else I should pay attention to?Thank you very much!!

author: ataradov
author_rank: Super Contributor
timestamp: February 28, 2022, 10:44:48 pm
content: I2C is possibly the least critical interface. Your layout is fine.

author: isometrik
author_rank: Regular Contributor
timestamp: February 28, 2022, 10:54:09 pm
content: The ultimate I2C reference is NXP (previously Philips, the inventors of I2C) document # UM10204 :I2C-bus specification and user manual:https://www.nxp.com/docs/en/user-guide/UM10204.pdf* Can I2C traces go under other components in the same layer (resistors, ESP32)"You can route signals under the ESP32 without issues.I would personally refrain from routing signals between SMD resistor pads, but it's not a huge issue if you do so.* Do they have any requirements on track widthNegative. 10 to 12 mils (0.010" to 0.012") would do the job. Feel free to go above or below these numbers.* I understand that they don't need to be routed as differential pairs. In my case they have 21mm and 24mm long. Do I need to match them?Negative. I2C signals are low speed, and length matching is not required.* Do I need a ground trace in between them?Negative. You can, but it's not required.* Is there anything else I should pay attention to?Excessive capacitive load will slow down the maximum bus speed, but it's not an issue unless you have many devices connected on the bus, or have mega-wide and mega-long signal traces.
I2C tuner datasheet. - Page 1
Forum section: electronics / projects

author: firewalker
author_rank: Super Contributor
timestamp: September 08, 2019, 11:20:24 am
content: I came across to a seemingly pretty nice I2C tuner (QSD-MT-S78). I am not able to find any dtatasheet. The device it came from was missing the logic board, and I can't sniff the I2C bus.Does anyone have the datasheet?http://www.szqsd.cn/product_show.asp?id=125

author: amyk
author_rank: Super Contributor
timestamp: September 08, 2019, 06:38:49 pm
content: TDA6509AandSP9889HNwhich other sites indicate is a clone of theTDA9887HN.
i2cdetect doesn't catch ANY address (no toner chip Ti046b1 device detection) - Page 1
Forum section: electronics / projects

author: nouvelle_adr
author_rank: Contributor
timestamp: December 12, 2018, 09:39:19 am
content: I have ti046b1 chip (Serial I2C F-RAM) to read (Dell Printer cartridge memory).I tried to read it with my raspberry Pi 3, so I connected SDA SCL VDD GND as shown in pictures, but when I run the command "i2cdetect -y 1" on my Raspberry it shows no device connected to I2C interface (empty) like that:pi@raspberrypi:~ $ i2cdetect -y 10 1 2 3 4 5 6 7 8 9 a b c d e f00: -- -- -- -- -- -- -- -- -- -- -- -- --10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --70: -- -- -- -- -- -- -- --do you have any idea to solve that ?- I tried by inverting (swiping) SDA SLC connections- I tried by pulling-up to 3.3V SDA and SCL with 10k resistors (as statedhttps://www.raspberrypi.org/forums/viewtopic.php?t=7664) to end-up with 1.5K pull-up resistance- I checked that there are a built in pull-up 1.8K resistors in the raspberry 3 (see the ohmmeter measure with Pi powerd off of course)- I tried to change I2C baudrate by the command:**sudo modprobe -r i2c_bcm2708****sudo modprobe i2c_bcm2708 baudrate=100000**tested with 100KHZ, 200KHZ, 400KHZ, 800KHZ, 1200KHZ (the result is the same- I have put a scope probes on SCL and SDA when the printer is powered on to see how it negociate (see the piture below)could you please help me to solve that ?And to anticipate your first question : I checked all the connections for this wiringscope probes on SCL and SDA when the printer is powered with the chip is inside[Scope probes on SDA SCL][Circuit Chip and schematic]Existing pi 3 built-in pull-up 1.8K proven (pi is not powered)[i2cdetect response][i2cdetect is enabeled][Wiring to my Raspberry Pi 3]a brilliant guy here "Fang"https://www.eevblog.com/forum/projects/lexmark-toner-chip-ti046b1/msg2024053/#msg2024053suggested to me to do reverse engineering on printer firmware to prevent it to check & update toner memory, but I cant do this due to packed firmware (but I love this idea to get rid of toner industry)Howardlong said herehttps://www.eevblog.com/forum/projects/lexmark-toner-chip-ti046b1/msg925735/#msg925735that this chip uses 10 bits addressing,do you know how to make my PI 3 read/write 1 bits addressing ?
I2S DAC or I2S Class-D amplifier (TI TAS57xx) series - Page 1
Forum section: electronics / projects

author: davorin
author_rank: Unknown
timestamp: January 26, 2016, 06:46:24 pm
content: Following situation...I have a Carambola2 WLAN module with SPDIF and I2S outputs running some down sized version of Volumio audio player (mpd in the back)...Now also have a Keystone DAB+/FM radio module outputting also I2S....Looked at the Class-D amplifier with I2S input from TI, TAS5760M....looks interesting as it would keep components count low...and volume can be controlledvia I2C from the Volumio application...Someone already had experience with this Class D amplifier family? Would it be audible when switching between two different I2S audio sources, taken into account sample rate changes apply as well?Or better go with two seperate I2S DACs and an audio multiplexer/volume control at the back? Dunno if something like that exists....
I2S to TDM conversion help - Page 1
Forum section: electronics / projects

author: tokyoscarab
author_rank: Newbie
timestamp: October 25, 2024, 08:15:25 pm
content: Hi, I'm working on a project for a client and some of the parts being used in it are basically locked in and not within my power to swap. Without being able to go into some details of it, I will give my best explanation of what I'm trying to do. We are using an Analog Devices ADV7623. It is effectively an HDMI hub chip. The 7623 allows us to strip out the audio signal in real time, send it off to an audio dsp and then allow injection of the audio back into the video signal in real time. We already have all of the encoding / de-encoding stuff handled with Dolby. The audio dsp my client is fixed on using works great for many of the things we need in our solution, but does have one downside, the audio input it accepts is TDM. Now I'm not as familiar with the inner workings of TDM and this is where I would love some advice on this. We need to get the audio into this DSP and then back out into the 7623. What is the best / easiest way to handle this conversion?

author: moffy
author_rank: Super Contributor
timestamp: October 25, 2024, 10:46:57 pm
content: There is a nice article at:https://www.analog.com/media/en/technical-documentation/technical-articles/MS-2275.pdfIt talks about the various audio formats/interfaces and they state that:"There is no standard for TDM interfaces, such as the Philips standard for I2S. This means that many ICs have their own slightly-different flavor of a TDM implementation"Perhaps a small FPGA might be the best approach.

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 26, 2024, 02:05:44 am
content: Maybe a RP2040 will do the trick, specifically using the PIO blocks? Cheaper than a FPGA and easier to program.

author: SeoulBigChris
author_rank: Regular Contributor
timestamp: November 19, 2024, 07:33:30 am
content: Do you need any help on the ADV7623 side of things? I've designed and built a few products around this chip set. I haven't dug into the audio side of things yet, although I have a potential new application I'm looking at.
I'd like to buy a few encoders and knobs to fit them that are breadboard friendl - Page 1
Forum section: electronics / projects

author: cdev
author_rank: Super Contributor
timestamp: September 27, 2017, 04:57:04 am
content: One will probably end up eventually tuning SDRs, etc. so I would like a lot of encoder resolution pixels or whatever they would be called.. the others will likely be used for less demanding tasks, maybe ten or twenty digits of spin is probably okay..Does anybody have any favorite encoders that wont break the bank? Only one of them has to be "nice" but I would still like for it to be as cheap as possible. The big one might eventually be getting a lot of use.. I'm just fooling around, dont really have any specific requirements except flexibility, I hate to buy parts I can't use in projects serially until I find one thats worth keeping together.

author: dmills
author_rank: Super Contributor
timestamp: September 27, 2017, 02:28:15 pm
content: Nice usually means optical in this game.If you have 5V available then Bourns make some decent stuff in convenient packages, but it is not cheap (£25 or so) if you want a 128 cycle per rev quadrature part for example (You can get 512 counts per rev out of these by some cleverness with a state machine triggering on both edges of both gray code bits), these are nice for the good encoders.Much lower res is available from the same company in mechanical types, but be a little careful here, they bounce and often have the relative timing of the A and B outputs defined poorly enough to make the quad counting trick to get more resolution a non starter.Avago/Broadcom have some nice stuff in the HEDS series (Especially as they come in up to 1024 cycles per rev), but it can be mechanically a bit of a faff to use, much of this stuff is intended to fit onto motors to close servo loops rather then front panel usage, but it can still be useful if you for example want to add some mass for inertia on a tuning knob.Regards, Dan.
i'd like to design the Sony PSOne mobo, reproducing it with an fpga - Page 1
Forum section: electronics / projects

author: legacy
author_rank: Super Contributor
timestamp: July 19, 2014, 11:54:20 am
content: Sony PlaystationOne (aka PsOne)'s motherboardhi guysi am not an Eagle/OrCad/KiCad/whateverCad expert but i have a nice projecti'd have modified the PsOne's case in order to accept custom boardsso i am currently using fpga breakout(1) mounted on 1000-holes rapid prototyping boardwhich has found its limitsin order to go on i'd better build my own motherboard to be put in the PsOne's casemain problems:1) how do design connectors, Sony has custom connectors, e.g. the Pad, the PowerIn, the Video-Oudio-Out connector ?2) how to design a PCB that has the same shape (and holes at the right position) of the PsOne mobo ?what are your advices ?let me know(1) about fpga, with a friend of mine we are designing a SoC which tries to emulate MIPS_1 plus a VDU plus (eventually) a GPU.at the moment we have a SoftCore not completely validated plus a text-VDU compatible with the PsONE'LCD (PAL version)we are still missing the PAD interface and a lot of things, but … the purpose is- learn VHDL- learn CAD design about solid design- learn CAD design about PCB- learn how to realize good and complex PCB- learn a bit of game programming- having fun

author: Rerouter
author_rank: Super Contributor
timestamp: July 19, 2014, 11:32:39 pm
content: For both problems 1 and 2, i would recommend grab an old original circuit board, steal the connectors, (from there you may be able to find equivalents), and measure the hole centers and board shape, This is what most other people have to do when an enclosure lacks a factory released dimensioned diagramAs for the layout, it sounds like you have played a little with a pcb editor, but i will admit this project is diving in the deep end a little bit,there are a few key topics which i would recommend you read up on before trying to lay it out,- Path of least impedance (At high speeds current wants to flow through the ground plane directly under the signal trace)- Controlled impedance traces (Variations in impedance such as a signal going over a break in the ground plane can distort signals )- Matched length traces (Say your clock has a shorter path than your signals into a latch, it would make the latch miss your input)

author: legacy
author_rank: Super Contributor
timestamp: July 20, 2014, 01:57:13 pm
content: Quote from: Rerouter on July 19, 2014, 11:32:39 pmdone!i have unsoldered connectors from an old died board, fortunately i have not damaged the plasticQuote from: Rerouter on July 19, 2014, 11:32:39 pmOKQuote from: Rerouter on July 19, 2014, 11:32:39 pmyeah, it sounds hard, i am also wandering if i'd better realize a "backplane" pcb in where to put an fpga breakoutthat means reduction issues for the 70%, what do you think ?connectors are:- 1x video out, PAL synchronism- 1x audio stereo out- 2x PAD (joypad) in/out, it is similar to SPI, 3.3V driven
I'm a young player and I found a trap! - Page 1
Forum section: electronics / projects

author: ElectroNub
author_rank: Contributor
timestamp: April 26, 2015, 04:01:31 am
content: I'm working on a power supply project using a few cheap ebay parts and I found a problem that is stumping me.Using a $2 dollar panel voltmeter with 3 wires. Common ground with separate power and sense wires.And a $2 dollar 3 amp PWM module.I'm making a little power box that I can plug in any of my wall warts and make it adjustable.Anyhow, I was whacking my brain against the walltrying to figure out why this simple circuit was not working correctly. It turns out that my PWM module is switching the LOW side!My panel meter is not happy with this configuration. I can hook up all the meter wires to output and it works OK but the meter shuts off under 3 volts. My PWM control goes down to 1.2 volts and this meter is capable of reading 1.2 volts.Is there a trick to wire this up and make it work as intended?Or is this low side switching with a common ground meter pooping on my parade?

author: kjs
author_rank: Regular Contributor
timestamp: April 26, 2015, 04:57:14 am
content: that's an unusual setup. Most of these switchmode controllers have input and output ground completely and hard connected. What type is it? The usual LM2577 and LM2596 ones would work just fine..If it really has a separation there you unfortunately are hosed with that DVM as the supply ground and test ground is identical.Edit: just remembered.... I had several of these 3-wire DVM's (38 out of 50!) which had the jumper (solder) for the 2-wire version still in. You better check whether yours has that too. That would also hose up things if you short input and output. The solder jumper is just after the pads where the + and test wires are soldered to. Looks like they use it for faster testing and then sometimes forget to take it out for the 3-wire version.(picture is of a 2-wire and I circled the "jumper")

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 26, 2015, 06:14:19 am
content: Use a diode and capacitor as a charge pump to power the meter.

author: Zero999
author_rank: Super Contributor
timestamp: April 26, 2015, 09:22:40 am
content: Quote from: kjs on April 26, 2015, 04:57:14 amI doubt it's a switch mode controller. It seems like it's a PWM control unit designed for motor speed control and is completely unsuitable for use as a switched mode power supply.

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 26, 2015, 03:14:30 pm
content: Maybe that's his intention. Apart from motor and resistive loads, there are a few electronic loads (e.g. some LED modules) that are designed specifically to run from PWM.

author: kjs
author_rank: Regular Contributor
timestamp: April 28, 2015, 12:30:00 am
content: Looked to me like he's intending to build a power supply (lab) but let's wait until he comes back...... Could well be that he has chosen the wrong module or wants to use it for something different.
I'm looking for an I2S Audio DAC - Page 1
Forum section: electronics / projects

author: SpiderElectronics
author_rank: Contributor
timestamp: December 11, 2012, 03:12:29 pm
content: Hi everyone.A design I am refreshing currently uses an AK4366 Audio Dac with I2S interface.It's a 24 BIT Audio DAC, up to 48khz sampling rate, with 3.3v VCCI can't find a supplier in the UK for this chip anymore. Neither Farnell, DigiKey nor RS stock it.Can anyone suggest a reasonable quality Audio DAC with I2S Interface that I can use in place of this?Doesn't need to be an exact replacement.

author: Christe4nM
author_rank: Unknown
timestamp: December 12, 2012, 04:50:10 pm
content: I remembered my stm32 discovery board has a Cirrus Logic one, so I looked it up for you: it's the cs43l22.http://www.cirrus.com/en/products/cs43l22.htmlIf this isn't what you are looking for try their website for similar devices.

author: jeroen74
author_rank: Frequent Contributor
timestamp: December 12, 2012, 09:06:17 pm
content: wm8524Carried by Farnell. Cheap as chips too.
IBIS and S-Parameters  - Page 1
Forum section: electronics / projects

author: joniengr081
author_rank: Regular Contributor
timestamp: September 03, 2023, 08:29:54 am
content: Hi, I found two simulations models IBIS and S-Parameters. What is the difference between them ? I know they are different then SPICE which we use to simulate the analog ICs in circuit but if we talk about IBIS and S-Parameters then how do we differentiate them ? I know that IBIS stands for "Input/output Buffer Information Specification" and is used primary for digital IC switching or digital I/O modelling. What are S-Parameters ? and how they differ then IBIS models ?