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

• Is there any other similar chip that can replace MIC5842YN, please help!!
  Posted by daisizhou on 22 Jan, 2022 14:39
• 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
  

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• #1 Reply
  Posted by abdulbadii on 23 Jan, 2022 05:43
• 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
• #2 Reply
  Posted by Ian.M on 23 Jan, 2022 06:15
• 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
• #3 Reply
  Posted by daisizhou on 23 Jan, 2022 10:35
• 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?
  
  

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• #4 Reply
  Posted by retiredfeline on 23 Jan, 2022 10:42
• How about the tpic6b595?
• #5 Reply
  Posted by daisizhou on 23 Jan, 2022 21:26
• The following picture is the schematic diagram, U2 and U3 are MIC5842YN
  
  

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• #6 Reply
  Posted by fzabkar on 23 Jan, 2022 21:31
• I like the 74HC164 + ULN2824A solution. In fact I have had to make little daughter boards on several occasions to circumvent similar problems.
• #7 Reply
  Posted by daisizhou on 24 Jan, 2022 00:03
• Is 74HC164 + ULN2824A the best solution? Can you check for me? The circuit schematic is here
  
• #8 Reply
  Posted by fzabkar on 24 Jan, 2022 00:42
• 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.
• #9 Reply
  Posted by daisizhou on 24 Jan, 2022 01:04
• 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
  
• #10 Reply
  Posted by fzabkar on 24 Jan, 2022 01:19
• So it's 5V TTL logic referenced to -12V. I can't see a problem with that. Should be OK.
• #11 Reply
  Posted by daisizhou on 24 Jan, 2022 01:23
• This is the optocoupler signal
  

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• #12 Reply
  Posted by daisizhou on 24 Jan, 2022 01:29
• 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.
• #13 Reply
  Posted by daisizhou on 26 Jan, 2022 08:13
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  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
  
  
• #14 Reply
  Posted by daisizhou on 26 Jan, 2022 13:39
• 
  I drew a circuit schematic to replace the MIC5842YN, please help me to check if the pin definitions I drew are correct, thanks
• #15 Reply
  Posted by voltsandjolts on 26 Jan, 2022 14:24
• 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
  
• #16 Reply
  Posted by daisizhou on 26 Jan, 2022 22:50
• 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