Is there any other similar chip that can replace MIC5842YN, please help!! - Page 1
Forum section: electronics / repair

author: daisizhou
author_rank: Super Contributor
timestamp: January 22, 2022, 02:39:30 pm
content: MIC5842YN has been discontinued, can anyone tell me to use another type of chip instead of using it?Preferably a complete replacement, I don't want to modify the circuit

author: abdulbadii
author_rank: Frequent Contributor
timestamp: January 23, 2022, 05:43:39 am
content: https://octopart.com/mic5821yn-microchip-66526228Similar parts are not intended to be cross-references and may not be drop-in compatiblehttps://octopart.com/mic5842yn-microchip-66803473#SimilarParts

author: Ian.M
author_rank: Super Contributor
timestamp: January 23, 2022, 06:15:07 am
content: Something odd here! Microchip list MIC5842 status as 'In Production':https://www.microchip.com/en-us/product/MIC5842and Microchip Direct have stock of the YN (PDIP) package with dates additional stock is expected:https://www.microchipdirect.com/product/MIC5842YN

author: daisizhou
author_rank: Super Contributor
timestamp: January 23, 2022, 10:35:04 am
content: I don't know why there are so few brand new ones on the market, many of them are refurbished old chips for sale.Can I use 74HC164+ULN2824A instead of MIC5842YN?

author: retiredfeline
author_rank: Frequent Contributor
timestamp: January 23, 2022, 10:42:58 am
content: How about the tpic6b595?

author: daisizhou
author_rank: Super Contributor
timestamp: January 23, 2022, 09:26:33 pm
content: The following picture is the schematic diagram, U2 and U3 are MIC5842YN

author: fzabkar
author_rank: Super Contributor
timestamp: January 23, 2022, 09:31:27 pm
content: I like the 74HC164 + ULN2824A solution. In fact I have had to make little daughter boards on several occasions to circumvent similar problems.

author: daisizhou
author_rank: Super Contributor
timestamp: January 24, 2022, 12:03:05 am
content: Is 74HC164 + ULN2824A the best solution? Can you check for me? The circuit schematic is here

author: fzabkar
author_rank: Super Contributor
timestamp: January 24, 2022, 12:42:30 am
content: I would be careful with the logic levels. These would be determined by the voltages on pins 4 and 5. You may need a CMOS device for this. I can't make out the Vdd voltage, but logic ground seems to be -12V.

author: daisizhou
author_rank: Super Contributor
timestamp: January 24, 2022, 01:04:49 am
content: MIC5842YN (p1, p4, p8, p9) access -12v voltage,p2 access SCK signal,p3 access MOSI signal,p5 (VDD)access -7v voltage,p6 output signal to U3 another MIC5842YN,p7 input CS signal

author: fzabkar
author_rank: Super Contributor
timestamp: January 24, 2022, 01:19:33 am
content: So it's 5V TTL logic referenced to -12V. I can't see a problem with that. Should be OK.

author: daisizhou
author_rank: Super Contributor
timestamp: January 24, 2022, 01:23:15 am
content: This is the optocoupler signal

author: daisizhou
author_rank: Super Contributor
timestamp: January 24, 2022, 01:29:30 am
content: You mean 74HC595+ULN2803 is the best solution? I don't understand why the original author used MIC5842YN (80V withstand voltage), but the 50V MIC5841 seems to work normally.

author: daisizhou
author_rank: Super Contributor
timestamp: January 26, 2022, 08:13:08 am
content: I captured the waveforms of the MIC5842YN pin2 and pin3 clock and data pins.And measured the pin voltage of the chip on the spot.The preliminary plan is to use 74HC595+ULN2803 to make a small PCB, and design the pin definition to be the same as MIC5842YN, insert it into the original PCB board instead of MIC5842YN.I hope you can give me some advice, thank you

author: daisizhou
author_rank: Super Contributor
timestamp: January 26, 2022, 01:39:26 pm
content: I drew a circuit schematic to replace the MIC5842YN, please help me to check if the pin definitions I drew are correct, thanks

author: voltsandjolts
author_rank: Unknown
timestamp: January 26, 2022, 02:24:38 pm
content: The HC595 and ULN2803 are a good option and have good part availability.For future reference there is also these options:NPIC6C596and similar fromTINPIC6C595NPIC6C4894

author: daisizhou
author_rank: Super Contributor
timestamp: January 26, 2022, 10:50:10 pm
content: Fault damage is generally a breakdown or short circuit of one or several Darlington tubes in the Darlington array.So I designed separate self-contained components that can be replaced individually if damaged。I drew the 74HC595 schematic from 10-pin, 11-pin, 12-pin, 13-pin, 14-pin, 15-pin, 16-pin, 17-pin, 18-pin, is the connection correct? I'm afraid my understanding is wrong