Need more logic ICs, what ones ? - Page 1
Forum section: electronics / beginners

author: lordvader88
author_rank: Frequent Contributor
timestamp: February 27, 2018, 01:52:24 am
content: I have a few types of common logic ICs, barely played with them yet. Soon I'll have a bunch of DIP switches, waiting til then.I have 2-4 of eachcd4001becd4011becd4007cd4017behcf4024becd4026becd4051becd4081bpcd40106Bsn74hc14nsn74hc595nand some555lm7555What are some more common ones u folks don't see on the list ? I don't know or remember what most of these really do.I need some shift registers, divider/counters?, don't think I have 7-segment display chipsI just want more so that when I want to make something common/average hobby stuff, I don't have to wait months.So recommend some please (and order pizza too please)

author: amspire
author_rank: Super Contributor
timestamp: February 27, 2018, 02:59:55 am
content: Analog switches like the 4051/52/53 and the 74HC4051/52/53 are handy to have. I agree with Wilfred - I wouldn't bother stocking logic chips in general.Buy some Arduino compatible boards instead like:https://www.aliexpress.com/item/USB-Nano-V3-0-ATmega328-16M-5V-Micro-controller-CH340G-board-For-Arduino/32664369950.htmlhttps://www.aliexpress.com/item/WEMOS-D1-Mini-Pro-16M-Bytes-External-Antenna-Connector-ESP8266-WIFI-IoT-Board/32761915000.htmlhttps://www.aliexpress.com/item/Mini-USB-ATmega32U4-Pro-Micro-5V-16MHz-Board-Module-ATMega-32U4-Controller-Pro-Micro-Replace-Pro/32838537588.htmlhttps://www.aliexpress.com/item/1pcs-STM32F103C8T6-ARM-STM32-Minimum-System-Development-Board-Module-For-arduino/32721357650.htmlAll these boards are cheap enough to be built into projects.Once you start using micros, you do not need to use that much logic ICs unless you are fixing pinball machines or something like that. I only buy logic ICs when I need to use them.

author: lordvader88
author_rank: Frequent Contributor
timestamp: February 27, 2018, 03:38:11 am
content: Quote from: wilfred on February 27, 2018, 02:09:02 amNo, the more parts the better, especially since it takes 2-3 months for stuff to get here.

author: SkyMaster
author_rank: Frequent Contributor
timestamp: February 27, 2018, 03:51:58 am
content: Quote from: lordvader88 on February 27, 2018, 03:38:11 amIt is 1-2 day(s) for stuff to get here when buying fromhttps://ca.mouser.com/

author: agehall
author_rank: Frequent Contributor
timestamp: February 27, 2018, 07:57:22 am
content: Get a few CPLD (or small FPGA) boards and you don't need much else for prototyping.

author: paulca
author_rank: Super Contributor
timestamp: February 27, 2018, 08:05:44 am
content: I bought a bunch of 74* logic chips when I just started out. I was watching Ben Eaters videos.ORs, NORs, ANDs, NANDs, XORs, Inverters etc. I think the only ones I have used where the XORs for latches. However the ones I actually ended up wanting where none of the above.595 shift registers, ripple counters and clock dividers are probably more useful.As stated by others, a single Arduino Nano can do the work of several dozen of these chips and the logic can be tailored to whatever you need with a few lines of code.Given that, shift registers, multiplexers, coders/decoders and counters etc. will compliment the Arduino and save you IO pins.

author: LeoTech
author_rank: Regular Contributor
timestamp: February 27, 2018, 10:40:40 am
content: Although you guys a mostly right on the fact that in today's world it is no longer necessary to stock all parts. But...for the average hobbyists who are not focusing on making a project ready for production, but instead for fun and to learn, to later be able to design real products, it still makes sense to stock of few of each common part.Having these common parts at hand makes it easier to learn through practical examples and "hey" if it is fun for you to wire basic logic chips up on a breadboard, then please do.So, please stop disencouraging people to stock up on common parts and bits, if they like rapid prototyping and tinkering. And just want to do it at a hobbyist level, and not as a professional EE for a company.Not everyone is designing products and buys in QTY of thousand.I myself usually order less than 10 of each part for prototyping, learning and experimenting.Leo

author: paulca
author_rank: Super Contributor
timestamp: February 27, 2018, 11:04:59 am
content: While I agree with your sentiment, the problem is that 74HC/LS logic chips are not common components these days. A single $3 microcontroller will do the job of dozens of them.So the only reason to stock a bunch of these chips is if you specifically want to play with discrete logic IC circuits, for purely academic or "fun" reasons. One of those reasons might be to learn how computers work, registers, buses, memory etc. "used" to be based on these chips. Ala Ben Eater and Jullian Ilett on youtube.If you are just buying the keep in stock for that time when you think, "Oh, I need a set of 4 AND gates", those times are so rare if you have an MCU that it's not worth stocking them.That said, you can buy batches of 5 ICs for about $3 from Chinese sellers on ebay. They tend not to mix them. So you would need to buy about 20 or 30 different versions to get a good range of them, costing $60-90 for chips you will probably never really use.

author: LeoTech
author_rank: Regular Contributor
timestamp: February 27, 2018, 11:17:40 am
content: Exactly,Those chips are indeed hard to get and most likely not economical worth it these days.But, as you said yourself, there still has to be room for people like Ben Eater, and this forum should not discourage these people! The road is the goal!On the accounts of FPGA, these are also not suited for small hobbyists and thinkers as they require good soldering skills and equipment, and the ability to write hdl and a programmer for these FPGAs, and the required knowledge.But MCUs definitely!Leo

author: danadak
author_rank: Super Contributor
timestamp: February 27, 2018, 11:54:06 am
content: Think about doing a couple of videos on PSOC where not only are many of thoselogic chips effectively inside the PSOC, but you can, over time, learn how tocreate and roll your own.http://www.cypress.com/training/psoc-101-video-tutorial-series-how-use-arm-cortex-m0-based-psoc-4From simple logic point of view most of these only need one line of code to start theminside the chip. Then over time you can start learning a little C where you use the muchgreater potential of PSOC. Its got a lot of analog inside as well as tons of digital. Thereare many project examples from simple to ones that fully utilize the PSOC.You can get started for $ 10 with this board. There is also a $ 25 board, "PSOC Pioneer",that is arduino footprint compatible (not code compatible), but I recommend the$ 10 board first as it the "complete high end" part on the board.http://www.cypress.com/documentation/development-kitsboards/cy8ckit-059-psoc-5lp-prototyping-kit-onboard-programmer-andAs with all CMOS ICs you have to observe input/output signal voltage/current limitations.In other words simply all inputs positive and ranging from ground to the Vdd supply voltage,in the case of PSOC either 0 - 5V or o - 3.3.Regards, Dana.

author: newbrain
author_rank: Super Contributor
timestamp: February 27, 2018, 12:24:20 pm
content: Many, many years ago I used to buy extra logic ICs...I still have a number of them (from plain TTL, to LS and S, to HC and HCT and some AC).For many 6502/68HC11 SBCs I built in the past, I eschewed sparse logic for a poor man approach to programmable devices: I used a fast enough flash as a general purpose LUT to generate all the needed decoding and enable signal.Nowadays, when I need a logic function I use a cheap and simple MCU (if speed is not of concern), ATtiny or similar - I'm not PICky.If higher speed or prototyping is needed, I often go for the PSoC path...moreover so when some processing is also in the picture.The PSoC creator schematic entry is not top notch but quite usable, so you can just layout your gates and pins, and change them as needed without turning on your soldering iron (Bob Pease might now be rolling in his grave)Only if the function is very simple, I buy logic ICs, though sometimes, after prototyping on a PSoC, I go back to a physical implementation relying on the generosity of my left over IC collection.So, to conclude this boring tirade:Personally, I would not invest in stockpiling glue logic, especially if bought from Aliexpress/eBay or similar (as you say it take months to receive an order).

author: rstofer
author_rank: Super Contributor
timestamp: February 27, 2018, 03:09:42 pm
content: Here is one list, there are others on Googlehttps://en.wikipedia.org/wiki/List_of_7400_series_integrated_circuitsThe modern equivalent of a bin full of chips is an FPGA. It's pretty easy to find one with a million+ gate equivalents.It is just easier to write a line of code to create a 32 bit register than it is to populate a board with 4 sockets and wire-wrap them up. At this point, I think I am out of the wire-wrap business completely.Look at the datasheet for a 7474 D-Flop. The fastest it can run is 25 MHz (33 MHz for the 74LS74). It is dead simple to run logic in an FPGA at over 100 MHz and 200 MHz isn't really a stretch. With clever coding it might be possible to go much faster. Mostly I run my stuff at 50 or 100 MHz. It depends on which crystal is on the board. If necessary, I can use the internal PLL to get whatever speed I need.http://www.ti.com/lit/ds/symlink/sn74ls74a.pdf

author: paulca
author_rank: Super Contributor
timestamp: February 27, 2018, 03:12:33 pm
content: Most beginners will be running their logic chip experiments at 1Hz or less. Anything over 10Hz the LEDs just all light up

author: cowasaki
author_rank: Frequent Contributor
timestamp: February 27, 2018, 04:20:34 pm
content: What I do is when I find that I am buying the same IC a few times I will often order maybe 10 from China.

author: Vtile
author_rank: Super Contributor
timestamp: February 27, 2018, 05:12:10 pm
content: Stock only diodes and resistors.

author: eev_carl
author_rank: Regular Contributor
timestamp: February 27, 2018, 06:55:33 pm
content: You might find an older schematic that uses gates. I'm building a model railroad flasher with 4 NANDs. I know I can use a microcontroller, but then again, I don't even have a model train.

author: jmelson
author_rank: Super Contributor
timestamp: February 27, 2018, 10:03:52 pm
content: Quote from: agehall on February 27, 2018, 07:57:22 amRIGHT! Even the smallest CPLD, today, can replace maybe 20 TTL type chips. I use the Xilinx XC95xxXL series, the bottom of the line, the 9536 costs a little over $1 in small quantities, runs off a single 3.3 V supply, and is 5V tolerant on the I/O pins. This has 36 36-input gates that can be programmed to make up functions of up to 36 inputs. You can make counters, registers and all the common gate functions. It is possible enter the logic as 7400-type components in schematic form, but you will quickly find that VHDL (or Verilog if you prefer) is better. The best part is when you find it doesn't work the way you want, you can edit a line of VHDL, recompile and load it into the chip, and try again. Also, the simulation tools are a bit hard to learn, but being able to write a "testbench" of stimulus signals and then see what your logic will do, is a big help. You can view internal signals of your design with the simulator.Jon

author: danadak
author_rank: Super Contributor
timestamp: February 27, 2018, 10:28:17 pm
content: Here is a list, attached, of all the components in the 5LP parts. Noteyou cannot use them ALL at once, there is a limit, like FPGA, to totalresources used.But you can use many, duplicates or different, in a design.A resource module in PSOC is a component. The attached list shows allthe drag and drop components you can place on a schematic/part. Forexample I had one user requirement that needed a lot of 16 bit PWMs, I wasable to place 16, and still leave a lot of additional resources untouched.Note my list is a tad outdated, there are some newer components since I extractedthe attached list.And do not forget one can design ones own custom component, either using schematiccapture or Verilog.Regards, Dana.

author: rstofer
author_rank: Super Contributor
timestamp: February 27, 2018, 10:34:55 pm
content: Quote from: Vtile on February 27, 2018, 05:12:10 pmYou still need transistors for amplification and inversion. Each gate in the string of logic will be dropping about 0.6V of logic level. Pretty soon you're out of voltage. Thus the need for amplification, either at each gate (DTL) or every couple of levels. Inversion is a necessary function and in the very early days they got around it by using pulses that were inverted through transformers - not a volume conserving idea.I always liked diode logic and even DTL (an upgrade from RTL). A lot of interesting machines (including Burroughs mainframes) were built with diode logic.I would add some 2N2222A transistors to the shopping list. Extra credit for metal cans. At $2+ I think I would reconsider and use the 2N3904 at $0.21 each.For the truly talented, here is a microcomputer built entirely from MOSFETs. I saw this project a couple of years ago at the Computer History Museum in Mountain View, CA.https://monster6502.com/

author: Vtile
author_rank: Super Contributor
timestamp: February 28, 2018, 07:41:40 pm
content: @rstofer You are obviously correct the diode gates do need transistors as buffers. Another route is somewhat higher driving tension (a few tens of volts if small signal diodes are used), but even then the gate count would be small and would need careful potential and current analysis of the resistors involved to maintain the whole gate array at working potential levels (and rated currents).My suggestion obviously weren't meant to be too serious advice.PS. One funny (and flashy) hobby project could be making some functioning circuitry with LEDs as a gate diodes, but that is way too offtopic.

author: Old Printer
author_rank: Frequent Contributor
timestamp: February 28, 2018, 10:52:23 pm
content: I also watched a bunch of videos by Ben Eater ans Derek Molloy about logic gates. I bought a bunch of 74HCxxxx's etc and I did breadboard out a few circuits, but never got to many of them. Many of the chips have never been out of the sleeve, but I have em!not too. Big of an investment, and the are there for that rainy weekend/month that never seems to come along. Still glad I have them though, I was not paying attention when they were the way to go. For practical projects code sure does look like the way to go, but bread boarding basic logic circuits is a good way to teach yourself the principals.

author: lordvader88
author_rank: Frequent Contributor
timestamp: March 01, 2018, 05:58:23 pm
content: Yeah I want to learn some basics on the breadboard with chips. I do own an Ardrino, but I'm not using that yet, plus I barely know any programming.

author: Bassman59
author_rank: Super Contributor
timestamp: March 01, 2018, 08:10:35 pm
content: Quote from: lordvader88 on March 01, 2018, 05:58:23 pmPerhaps you should start by asking, "what do I want to implement?" and then look for the parts required to do that.

author: Wimberleytech
author_rank: Super Contributor
timestamp: March 01, 2018, 09:00:33 pm
content: I do not subscribe to the JIT approach for jellybean parts. The amount of money you spend on shipping your JIT buy, can purchase a lot of stock on hand.That is how I do it...not advising anybody else to do the same.------update-----------I can buy 5 cd4007 pdip on ebay, usa seller, free shipping for $2.99I can buy 5 cd4007 pdip from mouser for $2.10 + shipping. I am sure shipping is at least $8A single data point.

author: paulca
author_rank: Super Contributor
timestamp: March 01, 2018, 09:52:12 pm
content: Quote from: lordvader88 on March 01, 2018, 05:58:23 pmI recommend, Ben Eater on youtube, plus Jullian Ilett. Search for them. Jullian just made a rather bizarre traffic light set up with a 555 timer as clock and an eprom chip using address/data multiplexing and a latch. It's completely pointless but it's probably lot of fun to learn how epproms, addressing and latch stuff work.Then pick a project and order some parts. Depending on where you are you can find some free shipping suppliers, such as RS in the UK. If not, ebay. Shop around, order a bill of materials for the project and maybe throw in a few extras.If you are going to be working with almost any of the more advanced (than simple gate array chips) you will be needing a clock. I would suggest this is your first project. Ben Eater's 8bit breadboard computer starts with about 3 videos on his 555 clock. It's a brilliant little starter project and when you progress to counters, latches, bus transcievers, multiplexers and shift registers they will all use that little breadboard. It will be so hand you could even get it printed onto a PCB for running your projects.Alteratively you can just connect a digital pin of the arduino and use delay() to produce your clock, but... it's probably not as much fun.As to AND, NAND, OR, NOR, XOR... etc. gates. They aren't very interesting to play with. You connect an AND gate to two switches. When you press both the LED comes on. It does not getting any more interesting.If you want to try something a little more challenging just buy NAND gates (or NORs) as they are considered generic or root gates as all other gates can be made from combinations of them. In fact in the past computer chips where made exclusively with NAND gates as it was cheaper to produce all the same gates.https://en.wikipedia.org/wiki/NAND_logic

author: Wimberleytech
author_rank: Super Contributor
timestamp: March 02, 2018, 12:26:34 am
content: Quote from: wilfred on March 01, 2018, 11:12:33 pmOK, maybe I am a hoarder. That is what my wife would say.

author: amspire
author_rank: Super Contributor
timestamp: March 02, 2018, 01:02:34 am
content: I have a few tubes of old 18CV8 programmable ICs. If I need to breadboard some logic, I just program the chip. Most of the programs are just a few lines of code and one 18CV8 often replaces 3 or more logic chips. It can replace a big chunk of logic chips varieties and the speed is 10ns. Never have to add extra inverters to a design to get the right clock edge. Not low power (50mA), but for breadboarding, it doesn't matter.I did once have a collection of a few hundred logic chips, but I ended up getting rid of them. Many were the original 74xx series I had carefully preserved from the 70's.