Is there any other similar chip that can replace MIC5842YN, please help!!

[daisizhou]

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

[abdulbadii]

https://octopart.com/mic5821yn-microchip-66526228

Similar parts are not intended to be cross-references and may not be drop-in compatible
https://octopart.com/mic5842yn-microchip-66803473#SimilarParts

[Ian.M]

Something odd here!  Microchip list MIC5842 status as 'In Production': https://www.microchip.com/en-us/product/MIC5842
and Microchip Direct have stock of the YN (PDIP) package with dates additional stock is expected: https://www.microchipdirect.com/product/MIC5842YN

[daisizhou]

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?

[retiredfeline]

How about the tpic6b595?

[daisizhou]

The following picture is the schematic diagram, U2 and U3 are MIC5842YN

[fzabkar]

I like the 74HC164 + ULN2824A solution. In fact I have had to make little daughter boards on several occasions to circumvent similar problems.

[daisizhou]

Is 74HC164 + ULN2824A the best solution? Can you check for me? The circuit schematic is here

[fzabkar]

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.

[daisizhou]

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

[fzabkar]

So it's 5V TTL logic referenced to -12V. I can't see a problem with that. Should be OK.

[daisizhou]

This is the optocoupler signal

[daisizhou]

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.

[daisizhou]

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

[daisizhou]

I drew a circuit schematic to replace the MIC5842YN, please help me to check if the pin definitions I drew are correct, thanks

[voltsandjolts]

The HC595 and ULN2803 are a good option and have good part availability.

For future reference there is also these options:
NPIC6C596 and similar from TI
NPIC6C595
NPIC6C4894

[daisizhou]

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