hybridfree/eevblog-posts huggingface dataset:
IR camera stuck in Black/white, replaced a component to fix, need to ID it.  - Page 1
Forum section: electronics / beginners

author: TT_Vert
author_rank: Regular Contributor
timestamp: June 02, 2020, 12:55:47 pm
content: I'm fairly sure it's a SOT23 PNP transistor but I just want an opinion as i think there are variants that may exhibit this same behavior? In the image you'll see what I'm talking about but if i put my negative lead on on terminal 1 and the positive to terminal 2 I get .653Vf, if i leave negative on 1 and positive to 3 I get .643Vf, would this indicate this is just a standard PNP transistor? How can I perhaps see if there is anything special about it? I do not have an details and the component just says M6 on it.Thanks guysDave

author: Benta
author_rank: Super Contributor
timestamp: June 02, 2020, 04:34:24 pm
content: What do you mean by "stuck in B/W?"I've never heard of a colour IR camera.

author: mikerj
author_rank: Super Contributor
timestamp: June 02, 2020, 08:17:47 pm
content: The polarity indicates a PNP bipolar transistor, and the M6 marking means it may be a2SA812

author: magic
author_rank: Super Contributor
timestamp: June 03, 2020, 09:05:49 am
content: What makes you thing there is anything wrong with this tranny?

author: Brumby
author_rank: Unknown
timestamp: June 03, 2020, 12:15:51 pm
content: Quote from: Benta on June 02, 2020, 04:34:24 pmMy first reaction also.

author: Muttley Snickers
author_rank: Unknown
timestamp: June 03, 2020, 01:00:24 pm
content: Quote from: Brumby on June 03, 2020, 12:15:51 pmThe OP might be referring to a CCTV camera which is colour during the day and automatically switches to black and white at night or in low light conditions. On some cameras such as auto-domes the change over threshold can be adjusted to suit the local lighting conditions. Some other cameras also incorporate infrared illuminators and use an LDR or light dependent resistor to switch on the IR illumination.

author: Benta
author_rank: Super Contributor
timestamp: June 03, 2020, 03:55:44 pm
content: Quote from: Muttley Snickers on June 03, 2020, 01:00:24 pmThat's the only sane explanation I can think of.

author: Kasper
author_rank: Frequent Contributor
timestamp: June 03, 2020, 04:44:34 pm
content: Some cameras have a small motor to move an IR cut filter for day/night mode. Called IR cut filter switchers, they make an audible click when switching.That component could be the drive tranny for that motor, the problem could also be a stuck filter.A friend had one stuck half way open, he said half the screen was proper colors and the other half was black and white with a pink hue. I told him to shake it while forcing mode change between day and night (by turning lights on/off or covering illum sensor) and that fixed it.https://www.amazon.ca/Fityle-6pieces-Infrared-IR-CUT-Switcher/dp/B07B7612CF

author: TT_Vert
author_rank: Regular Contributor
timestamp: June 03, 2022, 07:48:47 pm
content: Quote from: Benta on June 03, 2020, 03:55:44 pmWow sorry for the delay, that is what I meant. I never got notified of replies, didn't mean to leave you guys hanging.
IR circuits  - Page 1
Forum section: electronics / beginners

author: bullonwheels
author_rank: Contributor
timestamp: July 01, 2018, 02:26:39 am
content: Hi guys, I would like to know, what exactly these attached circuit is exactly doing ?From what I see I think it is decoding IR data and extracting the carrier signal. Correct me if I am wrong.Also I am looking for a good IR learning circuit using discrete components. Can any one suggest me a tutorial or so ?Screen 2 I think It is a IR pass through ?

author: Paul Price
author_rank: Super Contributor
timestamp: July 01, 2018, 05:13:00 pm
content: Seems really a waste of time to try to build your own remote control IR receiver, these days, when you can salvage a tiny 3-pin complete IR receiver from any discarded DVD player, TV, or VCR.You don' want to extract the carrier, you want to extract the digital data stream from the remote's ultrasonic freq. (38-43KHz) carrier.But this circuit is not decoding the output digital data stream. The recovered digital output is just data, and without a decoder, could not be used to control anything.The top circuit would function to extract the data from the carrier if the remote receiver is just using an infrared photo-transistor to detect the remote signal and you are satisfied with poor sensitivity, working only over a small range of remote Xmiter distance, and also having poor immunity to room lighting or sunlight interfering with remote operation.Google remote control circuits and you will find tons of info on how they work.
IR Led and Phototransistor on the same package? - Page 1
Forum section: electronics / beginners

author: Flick
author_rank: Newbie
timestamp: June 26, 2014, 06:21:55 pm
content: Hi, guys!I've got this very old board(circa 1999/2000) that has this strange 'IR Led and Phototransistor' in one single package.This works fine, but I want to buy new ones, but I can't figure out it's manufacturer nor the model!Here's some pics:https://drive.google.com/file/d/0B8x2Zzv23LVvN0tablA5VVhGbUFEWmRsN254R3VLQTVRSUw0/edit?usp=sharinghttps://drive.google.com/file/d/0B8x2Zzv23LVvZVBOd2lwSWZZUXdCb0E5V09iekdtSHNKcWg4/edit?usp=sharinghttps://drive.google.com/file/d/0B8x2Zzv23LVveU9hdmdyN3NpZ2I5TTdxREpIazVLNE5TamhB/edit?usp=sharingCan anyone help me out?Thanks.

author: RazSlack
author_rank: Contributor
timestamp: June 26, 2014, 07:14:39 pm
content: "IR LED and phototransistor in a single package" pretty much clarifies as an opto coupler. They use it to electrically isolate signals. The pics are kinda noisy and I can't make much out of it, but I think you can hack a different part in.

author: Flick
author_rank: Newbie
timestamp: June 26, 2014, 07:38:21 pm
content: Thanks for you reply, RazSlack!But this is actually a 'reflective sensor'. It is used to 'read' a black/white pattern(much like a barcode) from a plastic block and send some ASCII to a computer.But thanks for you help!

author: Flick
author_rank: Newbie
timestamp: June 26, 2014, 07:52:39 pm
content: Well, I finally found it!It's an "Reflective Object Sensor" from Fairchild. The model is an QRD1114!
IR LED array tracker - Page 1
Forum section: electronics / beginners

author: Roeffus
author_rank: Newbie
timestamp: November 11, 2017, 01:58:13 pm
content: A little while ago I found a project named opentrack. Opentrack can track your head orientation and position by using IR LEDs and a camera.I found that many users used AA batteries and resistors to control the leds. "This can be made way more compica... efficient and easier in use" i thought to myself.----What do i want?High power IR LEDs which emit light in a width degree.efficiënt LED current sourcelong operating time (~20hrs @ max led power useage.)usb charging (0.5 A)charge feedback state with rgb(red = battery low no charger connecter device on, blue = battery charging device off, green= battery full charger connected)----Found:Leds:https://www.adafruit.com/product/38785mW/sr@100mA Forward voltage 1.4@100mA view angle 20 deg.(140mW)OS-3038F~80mW/sr@100mA Forward voltage ~1.5 @ 100mA view angle 30 deg.(150mW)Current source:http://www.instructables.com/id/Power-LED-s---simplest-light-with-constant-current/Battery:Ebay LiPo battery1200mAh 3.7v ~29.6hr (for only powering led's 100% eff.)charger:BQ24075battery fuel gauge:not that lucky. Just found I2C's, and a mController probably uses to much power.----Does anyone know a good battery fuel gauge for my application, or has some feedback about my parts?Thanks in advance

author: Benta
author_rank: Super Contributor
timestamp: November 11, 2017, 04:00:52 pm
content: A tip: for IR stuff, always check Vishay.
IR LED cone angle - Page 1
Forum section: electronics / beginners

author: FrankT
author_rank: Regular Contributor
timestamp: June 27, 2012, 01:38:29 am
content: I'm looking at this data sheet for an IRDA transceiver.http://www.vishay.com/docs/84672/tfbs4650.pdfIt says 'Link distance: 30 cm/20 cm full 15° cone'. Does anyone know if this is +/-15 degrees, or +/-7.5 degrees? I can't see anything else in the datasheet to clarify this. Other data sheets say +/- angle.

author: Short Circuit
author_rank: Frequent Contributor
timestamp: June 27, 2012, 02:30:39 am
content: Optical characteristics mention conditions "? = 0°, 15°" for the Output radiant intensity.I'd say this implies an angle of +/-15 degrees. Makes sense, since a total angle of 15 degrees seems impractically narrow.Maybe the Irda spec is more clear on the required angle?

author: hlavac
author_rank: Frequent Contributor
timestamp: June 29, 2012, 07:56:41 pm
content: You can power on the LED, take a webcam and look! Most webcams can see near infrared

author: SeanB
author_rank: Super Contributor
timestamp: June 30, 2012, 05:40:16 am
content: 15 degree cone means 15 degrees off the optical axis. Thus 30 degrees total.
IR led transmitter and receiver - Page 1
Forum section: electronics / beginners

author: u666sa
author_rank: Frequent Contributor
timestamp: November 12, 2024, 09:50:10 am
content: I have an unusual question. How the infra red LED's are called, the transmitter and receiver?What are common wave lengths?Most importantly, how they called in Russian? Because I went to a store and thought I'd buy me a set, but the old man asked how they called, and I had no idea. Not a bad store, they have everything. But to get something in particular I have to know how it's called, wavelength, etc, so it could be found.

author: xvr
author_rank: Frequent Contributor
timestamp: November 12, 2024, 03:09:28 pm
content: For pure infrared LED seehttps://www.chipdip.ru/catalog/infrared-ledsPhotodetectors -https://www.chipdip.ru/catalog/photosensitive
IR LED tx/rx for object detection - Page 1
Forum section: electronics / beginners

author: engineheat
author_rank: Frequent Contributor
timestamp: September 11, 2019, 02:46:07 am
content: Hi,I need a quick and dirty way to detect the presence of a small black matte object, using ArduinoI want to try using a IR LED like this:and the corresponding receiver:The object moves along a fixed track. At the location of interest, I plan to orient the two LEDs (tx/rx) facing each other, and if the object blocks the IR ray, the Arduino would get the signal.The challenge is that the object is small (2mm diameter). It's too small to block all the IR light. To better "focus" the IR beam, I want to build a conical opaque "cover" to the transmitting LED with a tiny 1mm or so opening so that the object can fully block the IR ray. Is this a good approach?Thanks

author: engineheat
author_rank: Frequent Contributor
timestamp: September 11, 2019, 02:46:52 am
content: Quote from: engineheat on September 11, 2019, 02:46:07 am

author: wraper
author_rank: Unknown
timestamp: September 11, 2019, 03:10:48 am
content: Is it possible to use photo interrupter sensor like in mouse wheel? How big distance there should be between emitter and receiver?QuoteIt's not something you should use. It's for IR remote control, way too sensitive so will catch even reflections from walls and needs signal to be modulated at certain frequency.

author: ledtester
author_rank: Super Contributor
timestamp: September 11, 2019, 04:48:50 am
content: A photo interrupter like wraper suggests is a better approach.You want to shield the detector so that it can only receive light from the emitter.https://www.rohm.com/electronics-basics/photointerrupters/what-is-a-photointerrupterThe detector is a simple photo-transistor.In a pinch you can use an LED:https://wiki.analog.com/university/courses/electronics/electronics-lab-led-sensorand there are a bunch of videos on youtube demoing this -- i.e. search for "using an led as a light sensor"

author: jackthomson41
author_rank: Regular Contributor
timestamp: September 11, 2019, 08:11:09 am
content: I would suggest you to simply use ultrasonic sensorHC-SR04, withIR Proximity Sensor in Proteusyou need to interface both receiver & transmitter while in ultrasonic sensor simply plug trigger and echo pin and detect the object.

author: mikerj
author_rank: Super Contributor
timestamp: September 11, 2019, 08:20:22 am
content: Quote from: jackthomson41 on September 11, 2019, 08:11:09 amHow on earth do you think a 2mm object is going to be reliably detected via ultrasonic sensors of that size?

author: Gyro
author_rank: Super Contributor
timestamp: September 11, 2019, 08:33:46 am
content: Quote from: wraper on September 11, 2019, 03:10:48 amAs you can see from wraper's photo, the interrupter sensors have a narrow slit in front of the IR receiver. Without this, you're unlikely to be able to cleanly sense a 2mm diameter object. With just an LED and phototransistor you'd probably just see a minor dip in amplitude.
Ir Light Or laser for door alarm? - Page 1
Forum section: electronics / beginners

author: Ian
author_rank: Contributor
timestamp: April 20, 2011, 01:34:08 pm
content: HiSo i wanted to build a door alarm. So i found this project online.http://www.robotroom.com/Comparator.htmlIt does everything i need. Except i have one problem, do i use Ir light or a laser? I was going to use ir but i cant see IR so that complicates things. But if i use laser then they have to be perfectly lined up, it only has to be a little bit off and i have a false alarm. So i was thinking of using IR light but lining that up would be hard. The reason i was thinking Ir light was because it is not as directional. By the way i am going to be using the thing on my bedroom door, so i dont wont to use read switches. Any suggestions?

author: XynxNet
author_rank: Regular Contributor
timestamp: April 20, 2011, 01:59:32 pm
content: Just use an IR-LED. Lining up IR is pretty simple because the LEDs don't have a tight fokus.If you really want to check, you could use a webcam. Most of them are still a little bit sensitive for (near) IR, although they usually have IR filters.

author: Psi
author_rank: Super Contributor
timestamp: April 20, 2011, 02:00:53 pm
content: There are many ways to do itSimplest is probably an IR led at the end of a tube (the tube insures there is only a small angle where the IR light can escape and reach the other side.Pulse the led at a specific frequency using a 555 or similarThe receiver is just an LDR or photodiode which can also be mounted at the end of a tube to reduce interfearence if needed. You feed the signal through a filter to filter-out all but the frequency your led is pulsing at. Then you can use a diode and capacitor to convert that to a on/off signal for when the beam is interrupted.

author: FreeThinker
author_rank: Frequent Contributor
timestamp: April 20, 2011, 02:10:19 pm
content: Quote from: XynxNet on April 20, 2011, 01:59:32 pmYou could try a digital camera or your camera on your phone, most will pick up bit of IR as said above

author: Ian
author_rank: Contributor
timestamp: April 20, 2011, 03:33:53 pm
content: how powerful of a IR led do i wont?

author: Zero999
author_rank: Super Contributor
timestamp: April 20, 2011, 06:31:45 pm
content: Quote from: Ian on April 20, 2011, 01:34:08 pmThat article annoys me: there's no schematic and when comparators are unused their inputs should be connected to opposite supply rails, not both to 0V which can cause instability and I don't understand why he didn't just choose an MCU with built-in comparators.

author: Neganur
author_rank: Unknown
timestamp: April 20, 2011, 07:55:20 pm
content: I used an IR-LED with 180mW/sr in a similar project.It has an angle of half intensity of +/- 10 degrees, you can see the corresponding light cone at a distance of about 5 inches in this video.

author: Ian
author_rank: Contributor
timestamp: April 20, 2011, 09:49:08 pm
content: thanks
IR over distance - Page 1
Forum section: electronics / beginners

author: remix
author_rank: Contributor
timestamp: November 03, 2022, 05:31:34 pm
content: Hello,i am having issues with two TSOP4838 38khz IR Receivers, both connected to ESP32 at the same time.One is half meter away, the other one is about 2 meters away, both connected using unshielded cable.With the same software, the one closer to the ESP32 works without issues, but the other does not.Connecting it to my oscilloscope, it's obvious that the rising time on both ir receivers is different.Chan 1 (Yellow) is the further receiver and chan 2 (blue) is the one closer to the esp32Can you help me understand why 1.5 meters of wire are causing the slow rising time ?

author: pqass
author_rank: Super Contributor
timestamp: November 03, 2022, 06:01:08 pm
content: Inductance?Try adding a 10-30k pullup resistor at the ESP32 input pin (yellow).

author: Manul
author_rank: Super Contributor
timestamp: November 03, 2022, 07:11:16 pm
content: That's because of cable capacitance and weak drive. The receiver has an open colector output (with internal 30k pullup). Although it can drive LOW at reasonable current, driving HIGH is only achieved through that 30k pullup. Include cable capacitance and you get slow rising edge (capacitance is being charged through pullup and it takes time).If you use long cables, either use low value pullup, like 2.2k or even less, or add a buffer to drive a cable (cmos output logic gate should do fine, may need to include small series resistor to reduce ringing like 56R or so).Edit: Oh, and you should really add some supply bypass capacitor directly on your TSOP4838 pins. Be careful with ceramics though. They may cause voltage overshoots and damage the IC if long cables are used. You want some ESR here. So small electrolytic (like 4.7u) plus a small ceramic is ideal. You can also use just a ceramic, but add a small series resistor like 1-3 Ohms.

author: EPAIII
author_rank: Super Contributor
timestamp: November 04, 2022, 07:36:30 am
content: This is an excellent demonstration of why transmission lines need to have lower characteristic impedance for higher frequency signals.

author: remix
author_rank: Contributor
timestamp: November 04, 2022, 09:27:28 am
content: Adding 2k pull up improved the rising time.Manul - I will later add the bypass capacitor as well.Thank you all

author: Manul
author_rank: Super Contributor
timestamp: November 04, 2022, 11:24:00 am
content: To be honest, the rising edge looks bad but not so so bad. I bet that part of your problem is that you have multiple edges detected simply due to slow rise time and noise. This is a classic case of why we need schmitt trigger inputs for slow/dirty signals. So you should add a buffer with schmitt trigger input before ESP32 for proper signal conditioning.

author: remix
author_rank: Contributor
timestamp: November 04, 2022, 11:36:03 am
content: Yes, you are right. I was measuring too fast for changes and sometimes i was getting wrong readings.It this particular case - IR is a slow protocol ~590us between pulses and i can easily compensate for the wrong readings in software.
IR Photo-Diodes/Phototransistors == IR LEDs ??? - Page 1
Forum section: electronics / beginners

author: Axel1973
author_rank: Regular Contributor
timestamp: January 08, 2012, 06:28:58 am
content: Hi there,im pretty much noob, so i need some backup on this one.over years i salvaged a lot of parts, also IR LEDs , phototransistors and/or photodiodes. lately im trying to "sort" the junk (now talking about pretty much Infrared Stuff only) into EMITTERS (LEDs) and IR Photodiodes/Phototransistors.There yet i figgured some problem.Often IR LEDs and some sort of Photodiode/Phototransistors seem to have similar casing/housing (often LED cases).Using my Multimeter in DIODE TESTING MODE and some USB Microscope/Webcam i started to sort "IR Emitting" parts from "non-emitting" parts. IR emitting parts can easily be identified using the webcams picture, since the webcam is much more sensitive to IR light than human eye.i also did some measuring on some parts using the multimeter in resitance mode and mV range and i figgured out that "some" IR emitting parts "seem" to act pretty sensitive to incoming light (lumi lamp shining) and/or body-warming (hand palm).some change massively its resistance on alternating lighting, some even seem to produce a small voltage up to 500mv. So now im pretty unsure if all those IR emitting things are "IR LEDS ONLY" or "maybe" some sort of IR Photodiodes anyway.So MY QUESTION now is:Are there any known 2-pin IR Photodiodes / Photodiodes, Phototransistors (All Light sensitive Parts) out there who would also do emit at least some IR light when used like a simple LED (resistor + part in forward direction).? Or is any IR emitting Part FOR SURE an IR LED?Thanks for any Advice/Help/Feedback!best wishesAxel

author: Rerouter
author_rank: Super Contributor
timestamp: January 08, 2012, 06:48:25 am
content: in a 2 pin package, a photo transistor shouldn't act as a ir led, or if it does, an incredibly weak one

author: IanB
author_rank: Super Contributor
timestamp: January 08, 2012, 08:29:01 am
content: Well in general what goes up must come down, and what goes in must come out. Which is to say that LEDs are also sensitive to illumination and can act as detectors, and phototransistors or diodes might emit some radiation if biased in the right way. When testing them you want to find out what they do best. The things that are strong emitters and relatively insensitive receivers are LEDs, and the things that are sensitive receivers and poor or non-emitters are the photodiodes or transistors.
ir pre heaters - Page 1
Forum section: electronics / beginners

author: ant17
author_rank: Regular Contributor
timestamp: July 27, 2020, 05:51:09 am
content: hi guys i built my own ir preheater with 300 watt quartz ir lamps with indutrial ramp and soak controller and it seem to hold the pcb at a set temperature after it has finnished ramping but it is very bright and was hoping to be a be able to use it with my microscope and i was worried about effect o my eyes is there any solutions or am worrying about nothing
IR preamplifier with decoder - need help - Page 1
Forum section: electronics / beginners

author: falexandru18
author_rank: Newbie
timestamp: August 30, 2021, 06:23:41 pm
content: I want to make a preamplifier for an IR diode, similar to LT1328 or CXA1511L/M, I want to be able to adjust the bandwidth. I need your help with a circuit or at least an IC equivalent to LT1328. The circuit must do what TSOP2438 (or similar) does but at a much higher frequency, preferably to be adjustable.CXA1511L/M I can't find it anywhere and LT1328 is not available in europe.I watched this video, but it doesn't have the demodulation part, where the burst is converted into bits.Thank you!

author: Terry Bites
author_rank: Super Contributor
timestamp: August 31, 2021, 02:00:51 pm
content: Hmmmhttps://ro.mouser.com/Analog-Devices-Inc/Optoelectronics/Infrared-Data-Communications/Infrared-Receivers/LT1328-Series/_/N-6qrgm?P=1y9993bZ1yyh4l4You might even be able to get a free sample from AD!

author: Terry Bites
author_rank: Super Contributor
timestamp: September 01, 2021, 12:32:03 pm
content: There are hardware decoders eg HT12D/HT12F and loads of decoder libraries for arduino etc. You can get ready buit IR to USB infra red sniffer copies. see this hackhttp://www.hifi-remote.com/wiki/index.php/JP1_-_Just_How_Easy_Is_It%3F#Installing_RMIR_and_preparing_it_for_use.Desiging your IR front end is a doddle. AD and Others offer tools to optimise the IR diode amplifierhttps://tools.analog.com/en/photodiode/
IR receiver - 1.8V? - Page 1
Forum section: electronics / beginners

author: Tantalum
author_rank: Regular Contributor
timestamp: February 10, 2019, 10:46:21 am
content: HelloIs there a 1.7-1.8V IR receiver available somewhere???I can't find any, everything seems to need at least 2.0V.Thanks

author: Twoflower
author_rank: Frequent Contributor
timestamp: February 10, 2019, 11:17:40 am
content: If you have still the 3.3V available and only the level of the data line is the problem you simply need a level shifter for that to go from 3.3V down to 1.8V.

author: Tantalum
author_rank: Regular Contributor
timestamp: February 10, 2019, 12:25:07 pm
content: Well, no I only have 1.8 available and and there is not much room left for a step-up boost converter.

author: Zero999
author_rank: Super Contributor
timestamp: February 10, 2019, 03:15:40 pm
content: This the only thing I could find, but it doesn't seem like it's what you need.https://datasheets.maximintegrated.com/en/ds/MAXQ617.pdfHow many are you building?If it's just the one off, then you'll probably find most ICs specified for 2V operation will work down to 1.8V, so long as the temperature isn't too low. Another thing you might want to consider is increasing the 1.8V rail to 1.9V or even 2V, which no doubt your 1.8V devices will tolerate.http://www.vishay.com/docs/82834/tsop942.pdfhttps://docs-emea.rs-online.com/webdocs/1301/0900766b813013b7.pdfThe only other way is to build your own, from op-amps but I doubt there's room for that.
IR Receiver Modules for Remote Control TSOP4838 - Page 1
Forum section: electronics / beginners

author: andybarrett1
author_rank: Regular Contributor
timestamp: March 11, 2020, 10:58:50 am
content: Hi Thanks for readingI am using a TSOP4838 IR Receiver as per circuit below into a 16F628 Microchip processor.All I need it to do is see the presence of IR and switch an output accordingly. All of that works fine.However I am finding after a period of good in service use, that the input is being triggered by a fridge turning on...or maybe a light switch, the oven thermostat ..... My circuit is on a battery supply so not coming down the mains..Reasoning it to be EMI. The device states that it it is EMI Shielded and have placed in a earthed metal bot but still the noise is triggering it. Yes I know I could use the pulses to eliminate the issue but I do need any IR to activate my output.Thinking further as i write it maybe the input to the Microchip that is seeing the spikes rather than the IR Device?Circuit as per enclosed file but I do have a 10K pull up on output of IR going to MicroprocessorAny advice welcomeThank you for readingAndy

author: StillTrying
author_rank: Super Contributor
timestamp: March 11, 2020, 11:55:04 am
content: All I need it to do is see the presence of IR and switch an output accordingly. All of that works fine.It's designed to see only 38kHz IR.You might be able to put a few pF of filtering between the TSOP4838 and uP input.Are all unused pins on the 16F628 set as outputs rather than left floating.

author: andybarrett1
author_rank: Regular Contributor
timestamp: March 11, 2020, 12:12:59 pm
content: "It's designed to see only 38kHz IR. "It is and that works fine....No problems in it working at all but it does trigger on a light turning on or any other noisy switch which is telling me it is EMI.Yes unused pins are set to outputsAndy

author: StillTrying
author_rank: Super Contributor
timestamp: March 11, 2020, 12:20:49 pm
content: Can't the uP check that the IR ON time is there solidly for >200us, any EMI noise spikes should be shorter than that.

author: andybarrett1
author_rank: Regular Contributor
timestamp: March 11, 2020, 12:29:41 pm
content: "IR ON time is there solidly for >200us"I do have a check on the input but might only be 50us....... so you might have got it for meI not thought of thatAndy

author: Buriedcode
author_rank: Super Contributor
timestamp: March 12, 2020, 07:06:02 pm
content: The output will be triggered by EMI and even with heavy filtering on VCC will have some random pulses. That's why we have IR protocols with specific timing, to prevent false triggers.I have used RC filters on those which greatly reduces the random pulses, but don't stop it picking up EMI - thats what shielding does. Values used have been 33-100R and 22-47uF cap. You might have to use lower resistor values depending on your VCC and the power requirement of the IR receiver - the ones I use operate on about 0.5mA so the voltage drop across the filter resistor is small.The output has an internal pull-up, but is usually about 33k. Putting a 10k in parallel with this can't hurt.
IR reciver and transmitter Question  - Page 1
Forum section: electronics / beginners

author: christos
author_rank: Regular Contributor
timestamp: July 13, 2014, 02:39:01 pm
content: hello.. i have a question about IR recivers and transmitters ..this is the circuit i want to buildhttp://www.circuitstoday.com/infrared-intrusion-barrieri want to build two of these but i dont want them to mix together..for example the TX(1) to the RX(2)..does the IR reciver works only for a specific frequency? or can i change it?if i can ,,can someone tell me how?also, how can i control the distance?

author: Asim
author_rank: Regular Contributor
timestamp: July 13, 2014, 03:14:31 pm
content: The TSOP1836 IR receiver only receives around 36KHz, so if you use this receiver and another IR receiver that responds to a different frequency, in this case you might get it to work.Quotechoose another one that is away from 36kHz like 40KHzkeep in mind that you will need to adjust the frequency of the transmitter to send at 40KHz.for controlling the distance you can change R5 and R6, this will control the current going to the IR transmitter which will control the distance.

author: christos
author_rank: Regular Contributor
timestamp: July 13, 2014, 04:44:01 pm
content: is there any RX IR that can be adjustable?i need to know

author: Asim
author_rank: Regular Contributor
timestamp: July 13, 2014, 05:04:36 pm
content: Not as far as i know

author: christos
author_rank: Regular Contributor
timestamp: July 13, 2014, 05:22:24 pm
content: ok thx
IR Spot sensor/alarm. - Page 1
Forum section: electronics / beginners

author: paulca
author_rank: Super Contributor
timestamp: April 07, 2023, 09:22:43 pm
content: Off the tip of the hat...A simple, cheap IR camera you hang over your bench (or where ever). It, much like an IR fire sensor but a little more touchy, will look for heat spots. If a heat spot gets above a certain temp, it raises an alarm.How cheap can you make it and how effective would it be?It's ... something that might light up a few seconds before you smell the magic smoke about to release... it might save you from what I did last week and ... touch the MCU to see how hot was while shorted and consuming about 20W.A 60*C orange light. 80*C Falshing orange. 100*C auidble alarm say. All adjustable.Note. The MCU was NOT 60*C, or 80*C... it's was Awwwwww fuc....!!! hot and 3 days heeling.

author: jpanhalt
author_rank: Super Contributor
timestamp: April 07, 2023, 09:37:59 pm
content: Internet:QuoteIn terms of temperature, 1100 nm is a lot hotter than I want my MCU to be running at.(See:attachment)

author: JustMeHere
author_rank: Frequent Contributor
timestamp: April 08, 2023, 12:38:15 am
content: Use the temperature sensor in the MCU.

author: barshatriplee
author_rank: Regular Contributor
timestamp: April 08, 2023, 12:15:22 pm
content: I think adding an LM35 or DS18B20 to your circuit will be more convenient.
IR trace on Sony remote - Page 1
Forum section: electronics / beginners

author: Unknown
author_rank: Unknown
timestamp: November 28, 2009, 03:21:11 am
content: I am attempting to build an IR remote receiver for a project I'm working on.I decided to test to see what my Sony remote output looks like to help see, firsthand, what the carrier frequency would be, so I cracked open a Sony remote, connected the IR LED to my new Rigol scope and started hitting keys on the remote. I figured I could lock on the carrier and take some measurements to see what's what.It wasn't that easy.First problem, I could not get a stable carrier to appear onscreen no matter where I set my triggering line. Not sure why, this is my first issue. However, when I paused the sampling, I could take some measurements. (Please check my math)I see an overall repeat of the cycle every 1200us (1.2ms), or 833Hz. This cycle goes through this: Voltage rises from about -1.5 volts sharply to +1.5 volts, then pulses about 24 times at 25us each for a total of 600us with +1.5V down to to +0.5V waveform. This 600us long section of pulses calculates out to be 40kHz. This completes half the overall cycle. The next half of the cycle (lassting 600us) causes the voltage to drop in a 1/4 of a sinusoldal waveform down to -1.5 volts.The overall cycle lasts 1200us (1.2ms), or 833Hz. (Is my math correct?)How is this an 80kHz carrier, or am I missing something? And why won't the scope get a stable triggering on this?I'll attempt to attach a photo of the scope trace.Thanks,Edward

author: cybergibbons
author_rank: Frequent Contributor
timestamp: November 28, 2009, 06:08:07 pm
content: This page here explains what is going on with the signal:http://www.sbprojects.com/knowledge/ir/sirc.htmYou'll want to set the scope to single shot trigger to capture a signal like this. The 40kHz carrier can be seen during the 0.6ms pulse.

author: dexters_lab
author_rank: Unknown
timestamp: November 28, 2009, 06:32:29 pm
content: also might help if you rig up an IR receiver circuit, it means you can see and work with the demodulated signal and also means you don't need to hack apart your remotes

author: Unknown
author_rank: Unknown
timestamp: December 05, 2009, 09:11:40 am
content: Great stuff! I obtained a IR receiver from sparkfun and with single-shot capture, I can totally see the sony command set, as described in the link provided by cybergibbons. And with this codehttp://www.rtfa.net/2008/12/31/arduino-infra-red-ir-remote-control, I was able to capture the actual codes (his codes were wrong for my Sony remotes, but the code basis worked).Thanks, everyone.

author: Raj
author_rank: Frequent Contributor
timestamp: May 23, 2020, 07:17:48 am
content: Why reinvent the wheel... The working of tv remotes he already been documented in huge amount of detail. It literally took me a day to make a simple 8 button tv remote that transmitted to a BPL tv (sanyo circuitry) and sky set top box
IR transmitter circuit 3V -> 5V - Page 1
Forum section: electronics / beginners

author: symbianas
author_rank: Regular Contributor
timestamp: September 20, 2025, 03:05:31 pm
content: Hi, in google I see a lot of different IR transmitter circuits and getting a bit confused.I have taken out old TV remote and the circuit looks like this:How do I adjust it to be driven from 5V and ESP32 GPIO pin? Do I just increase 2ohm resistor to 20ohm? Do I need additional resistor for transistor base?

author: Zero999
author_rank: Super Contributor
timestamp: September 20, 2025, 09:30:35 pm
content: That circuit looks wrong. It should be something like this.

author: symbianas
author_rank: Regular Contributor
timestamp: September 21, 2025, 08:52:16 am
content: That's what I thought but remote circuit is like I posted before.Would it mean that its forward 2.4V 300mA?How do you calculate transistor base resistor?For diode I would calculate that it needs ~22ohm resistor, I dont know exact specs of IR Led though:

author: Zero999
author_rank: Super Contributor
timestamp: September 21, 2025, 09:51:49 am
content: Forget reverse engineering a TV remote and salvaging.If you're making a new design then buy the appropriate parts. Since you're running off 5V, then you save power. Put two LEDs in series and run them at half the current. They'll output the same ore more light and last longer.The base current needs to be high enough for the transistor to pass the desired collector current. In this case achieving a very low saturation voltage isn't necessary, do you can safely go with IB=1/50to1/20IC. If IC = 150mA, then a base resistor of 1k should give adequate base drive, of 4.3mA.

author: xvr
author_rank: Frequent Contributor
timestamp: September 22, 2025, 10:34:03 pm
content: In the original design, the transistor is connected according to the emitter follower circuit (common collector). And the LED is drawn in the opposite direction.QuoteNoQuoteThe power supply voltage does not matter - the emitter follower operates as a current source with any sufficient supply voltage.But the output voltage of the microcontroller will determine the LED current. It equal (VMCU-Vbe)/REmmiter
IR2153 / LM311 class D amplifier repair - Page 1
Forum section: electronics / beginners

author: Herschel
author_rank: Regular Contributor
timestamp: June 21, 2025, 05:12:11 am
content: I bought a 400watt(not actually 400watts) class D audio amp which is based on IR2153 and a LM311 comparator. So, I was running it on ±42 volts(max it could handle is ±45volts), also i noticed that the 13005 transistor which regulates supply for ir2153 gets really hot. But I never mid about that because i was running it below the ±45volts limit. one day when I turned it on, the amplifier just stopped working.found out to be the 13005 transistor started to shorted out damaging the IR2153, 2N5401 and overloaded the lm311 comparator which eventually got damaged. But there wasn't any magic smoke. later I replaced all damaged parts and upgraded the 13005 to 13007 transistor. now i can even run it at ±56volts.But now when i tried to increase the volume, the low frequency starts to get crackling for some reason.first I suspect it was of fake Lm311 or IR2153 or 2N5401 but not,So I upgraded the 10uf capacitors powering the LM311 to 100uf but nothing changed.I was running it on ±56volts but nothing was getting warm except the 13007 transistor.

author: Herschel
author_rank: Regular Contributor
timestamp: June 21, 2025, 09:07:12 am
content: I think using a snubber network across each of the mosfets drain and source did reduce the crackling now i have to increase the volume more to hear the crackling. is there any way to calculate the proper snubber values for this? connecting a snubber across(parallel) to inductor or across the mosfets?

author: Vovk_Z
author_rank: Super Contributor
timestamp: June 21, 2025, 09:41:28 am
content: IDK, just guesses: You may put snabbers both to transformar and to fets (and, BTW you can find out which work best). Start with "light" ones (less capacitance, more resistance).Look at some examples with a similar frequency for values examples.
IR2184 alternative - Page 1
Forum section: electronics / beginners

author: toma315
author_rank: Newbie
timestamp: February 16, 2015, 07:44:06 am
content: Hello everyone, I'm new here.I'm trying to design a simple inverter, using a IR2184 to drive two IRFP260 in push-pull mode. However, the IR2184 is kind of hard to find, so I'm wondering if anyone know of an alternative IC I can use in place of the IR2184?Thanks much in advance.

author: Phoenix
author_rank: Frequent Contributor
timestamp: February 16, 2015, 08:53:56 am
content: IR make a huge range of thesehttp://www.irf.com/product/Gate-Driver-ICs-and-Controllers-General-Purpose-Gate-Driver-ICs/_/N~1njciiCan you define what features you need? Bus voltage, gate voltage, gate drive current, dead-time, complementery outputs, UVLO etc.The IR2184 appears to be in reasonable quantities at the big guys - digikey, mouse, RS, E14.
IR3315 current sense high side switch circuit explanation - Page 1
Forum section: electronics / beginners

author: johm
author_rank: Contributor
timestamp: April 03, 2015, 09:40:09 pm
content: Hello!I'd like to use the IR3315 as overload protection, amongst others, but I don't fully understand how to drive the input control signal.So:- If Vin is referenced to Vcc, when Vcc-Vin reaches VIH the output is ON. (OK, then) Is it alright to connect Vin to Vcc? In case Vcc is shorted to GND will it stop properly and rearm again after this WAIT time has passed?A bit of insight will be fully appreciated.Datasheet:http://www.irf.com/product-info/datasheets/data/ir3315pbf.pdfAppNote:http://www.irf.com/technical-info/appnotes/an-1118.pdf(page 10, section "Controlling IR331X by one wire")

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: April 03, 2015, 10:07:27 pm
content: IN is the on/off control - pull it low (up to 37v below Vin) to turn on.In the case of a fault trip, you need to turn off & on to restore outputThe device has no ground connection - it derives its internal supply from the current coming out of the IN pin.The diagram you show is wrong - look at the datasheet - th ediagram on the first page is fairly clear (though you usually don't need to look at the current feedback output, and it's drawn slightly unconventionally in that the supply is coming from the right)

author: johm
author_rank: Contributor
timestamp: April 03, 2015, 10:33:23 pm
content: That settles it then, thank you.
IR9035 transistor cant find datasheet, price or any other info - Page 1
Forum section: electronics / beginners

author: Bobeletronics
author_rank: Newbie
timestamp: June 23, 2020, 03:23:32 pm
content: Hi everyone, first time I run into a problem when I able to read markings off the part, but a google search gives no result. This transistor (marked Q on the board) from 18 years old miller welder.Can someone suggest how to find datasheet or replacement for the transistor?I know that it is international rectifiers brand. photo of the transistor attached.First line reads 109156, second I(diod sign)R9035, third 3k 1tMuch appreciated

author: AVGresponding
author_rank: Super Contributor
timestamp: June 23, 2020, 04:41:27 pm
content: The 9035 may well be just a date code, year 1990 week 35, the other semi in the pic seems to share the same year.There's a fair chance the six digit number is the equipment manufacturers own part number, with IR (International Rectifier) just putting their customers part number on one of their own parts.You might have to reverse engineer the circuit to figure out what it is, some good quality pics of both sides of the circuit board will help us help you.
IRAMS10UP60A 3-phase driver/ inverter - Page 1
Forum section: electronics / beginners

author: VoidsWarranties
author_rank: Contributor
timestamp: June 14, 2016, 07:47:21 pm
content: I got an IRAMS10UP60A driver out of a washing machine a few years ago and decided i would make a 115v 3-phase driver from it. I was planning on using an arduino and a pot to control it. the data sheet and possibly correct circuit of it are below. i have to supercaps for it but since i am new to these kinds of devices i am not understanding the voltages to the chip or if the extra caps, resistors, and transistor. would it be easier to just use 3 n and p-channel mostfets and make 3 half-bridges. sorry i dont have much of any work or trouble shooting to show. my main questions are if VSS for the chip if gnd or negative like -15v and if there is a way to bypass T/Itrip by simply holding it a voltage.

author: danadak
author_rank: Super Contributor
timestamp: June 15, 2016, 01:18:45 am
content: Here is a datasheet that discusses some of the design issues -http://www.farnell.com/datasheets/1750322.pdfRegards, Dana.
IRFP4668PbF Suitability in application - Page 1
Forum section: electronics / beginners

author: Vindhyachal.takniki
author_rank: Frequent Contributor
timestamp: May 21, 2017, 05:04:54 pm
content: 1. I have a application in which mosfet is used as switch.Max VDs = 84VdcMax Id = 100Adc continuous & 150Adc for 10secLoad is motorUsed 12 IRFP4668PbF in parallel.Vgs = 10V from system2. I was calculating what max current I can pass in single IRFP4668PbF.P(ja)max = [ T(j)max - T(a)max ] / RjaAccording to datasheetT(j)max = 175CT(a)max = 85C (in application max temperature can go to 85C)Rja = 40C/WPutting values in formulaP(ja)max = (175-85) / 40 = 2.25WId = [ P(ja)max / Rdson at T(j)max ] ^ 0.5Rdson at T(j)max = Rdson @175C = 3.1*9.7mohm = 0.03007ohmwhere 3.1 is normalizeing factor for Rdson at T(j)maxPutting values in formulaId = (2.25 / 0.03007) ^ 0.5 = 8.65A3. Comes out to be 8.65A per mosfet,I am using 12 in parallel so total current = 8.65*12= 103.80A4. Are these calculations correct?5. How to select correct heat sink in this?6. Also in datasheet Page 4 in SOA graph,continuous DC graph looking at 10A current, Vds is only 8V, as marked red in pic attached.Does that mean this mosfet can not work in my application as mentioned in point 1 like Vds=84Vdc & if Id/mosfet is 8.65A.Infact it looks from graph that at higher vds like above 10V, mosfet cannot pass more current than 1A, as marked green in attached pic.Or I am doing something wrong in interpreting SOA.

author: danadak
author_rank: Super Contributor
timestamp: May 21, 2017, 06:37:24 pm
content: You have to ballast the design to minimize Rdson device to device variationfrom taking too much current / power in a specific MOSFEThttp://web.mscsoftware.com/support/library/conf/wuc96/08a_para.pdfhttp://www.vishay.com/docs/71619/71619.pdfIf using them as a switch, but driven in a PWM application, or gatesbeing driving at significant rate then gate dissipation also has to beaccounted for.http://ww1.microchip.com/downloads/en/AppNotes/00898a.pdfRegards, Dana.
Iron Holders - Page 1
Forum section: electronics / beginners

author: msknight
author_rank: Regular Contributor
timestamp: February 07, 2022, 10:56:22 am
content: I have an Antex TC50 iron and the usual holder is the Antex H8B0060 ST6A but there are a few failure points. It is a slightly thinner iron than many, so trying to use the usual "coiled spring" holder, the iron disappears far enough down the spring to make retrieving it a bit difficult. I tried an Atten S-11 station but the ST6A holds the iron further up the iron shaft while if I use the S-11, the tip will end up touching the metal tunnel when it's resting, and under heat.The question is whether the tip touching the metal tunnel will cause a problem (I'm presuming that it will) and if so, what other stand can people recommend please?

author: jmelson
author_rank: Super Contributor
timestamp: February 07, 2022, 04:36:59 pm
content: I have a Weller station at work, (WSL station, WMP iron) most of it is great, but the holder is not. Bump the cord to the iron with your thigh, and the hot iron can fall out on your leg or foot. No, I don't have a video of me trying to avoid the falling iron, but it is quite a dance!So, first order of business is to make sure the iron can't fall out of the hoder easily.Jon

author: BILLPOD
author_rank: Frequent Contributor
timestamp: February 07, 2022, 06:57:25 pm
content: Good Morning Msknight, I bought this one for my TS100 iron and I love it. Amazon link:https://www.amazon.com/gp/product/B08TC4QHRT/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1The name is: YIHUA X-4 Premium Soldering Iron Holder .It was $21 USD about a year ago. My TS100 iron is quite small, so I'm sure this will work for you.

author: msknight
author_rank: Regular Contributor
timestamp: February 07, 2022, 09:38:42 pm
content: Quote from: BILLPOD on February 07, 2022, 06:57:25 pmThanks very much. I'll give that a look.

author: msknight
author_rank: Regular Contributor
timestamp: February 08, 2022, 08:28:57 am
content: I solved the problem. I took the bar from the broken stand and put it through the holes in the new one, so that the tip doesn't touch the top any more. Job done.I'm still presuming that the tip touching the sides of the holder is a bad thing.

author: Gyro
author_rank: Super Contributor
timestamp: February 08, 2022, 09:50:04 am
content: QuoteIt's probably not an issue in practice - as long as the surface isn't rough enough to abrade the tip plating. It will transfer a bit more heat to the stand, but from the photo, yours is double walled anyway. If it's made of steel, heat transfer wont be that efficient anyway.