[SOLVED] Voltage Regulator identification and substitution

Thread Starter

usagoal

Joined Nov 26, 2020
5
I have pictured is what I believe to be an LDO voltage regulator(?) I've been using google to help identify this part as much as possible. The package size seems to be SOT-23 thin. It has 162C printed on the top (my pic does not show it completely). I'm looking at replacements on digikey, but need advice (guidance), if possible, for a substitute. Measurements I've taken from a working board: the input voltage is around 7.2v (battery pack voltage) and the output is 3.3v. Thank you!voltage regulator.jpg
 

Thread Starter

usagoal

Joined Nov 26, 2020
5
Sigma, thank you for the reply. I've attached a better pic and it seems to me it is a "1". I agree the original picture was not too clear. The functioning board that I have also shows a 1 when I inspected under the microscope (in case my eyes were deceiving me).

I've also attached a very...very rough partial diagram/layout of the component in question with some surrounding connections. Pin numbers are for reference and under the assumption this is a "LDO voltage regulator". I removed the component from the board to verify the traces and any other connections. Seems like pin 1 is input voltage when I traced it back to source (battery). Pin 2 is ground as I can see it soldered to the ground plane. And pin 6 seems to be voltage out to a "potted" logic device? Pins 3 and 4 have absolutely no connections that I can see when I removed the component.

From what I've been reading from datasheets, pin 3 is typically used to turn the regulator on/off. This is the description from a datasheet to a potential replacement component:
"Enable pin. Driving this pin high turns on the regulator. Driving EN pin low puts the regulator into shutdown mode."
This "162C" has no such connection and seems to be "on" without an input on pin 3. I tested the good board and I did not get any signal from this pin, yet it was knocking the 8 volts from pin 1 down to 3.3 volts on pin 5.

Upon further research I found some potential replacements from digikey, however this pin 3 on/off dilemma has me a little stumped. Thank you and your thoughts are appreciated.
 

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Sigma229

Joined Apr 17, 2019
34
Sigma, thank you for the reply. I've attached a better pic and it seems to me it is a "1". I agree the original picture was not too clear. The functioning board that I have also shows a 1 when I inspected under the microscope (in case my eyes were deceiving me).

I've also attached a very...very rough partial diagram/layout of the component in question with some surrounding connections. Pin numbers are for reference and under the assumption this is a "LDO voltage regulator". I removed the component from the board to verify the traces and any other connections. Seems like pin 1 is input voltage when I traced it back to source (battery). Pin 2 is ground as I can see it soldered to the ground plane. And pin 6 seems to be voltage out to a "potted" logic device? Pins 3 and 4 have absolutely no connections that I can see when I removed the component.

From what I've been reading from datasheets, pin 3 is typically used to turn the regulator on/off. This is the description from a datasheet to a potential replacement component:
"Enable pin. Driving this pin high turns on the regulator. Driving EN pin low puts the regulator into shutdown mode."
This "162C" has no such connection and seems to be "on" without an input on pin 3. I tested the good board and I did not get any signal from this pin, yet it was knocking the 8 volts from pin 1 down to 3.3 volts on pin 5.

Upon further research I found some potential replacements from digikey, however this pin 3 on/off dilemma has me a little stumped. Thank you and your thoughts are appreciated.
Hello,

Thanks for the extra info as I am still looking.
But I think the chip is https://www.digikey.ca/en/products/...C72wkXo1zohsKKbOU9MIODdXZ-8pNwaMaAgtHEALw_wcB

I base that of the board with the code on it "U1C2" and that pointed me to the chip for the link I posted just now.

I will keep searching but based on what you said it is a power on off chip.

Thanks
Sigma
 

MrChips

Joined Oct 2, 2009
27,112
Hello,

Thanks for the extra info as I am still looking.
But I think the chip is https://www.digikey.ca/en/products/detail/microchip-technology/MCP1322T-32AE/OT/6244653?utm_adgroup=Integrated Circuits&utm_source=google&utm_medium=cpc&utm_campaign=Shopping_Supplier_Microchip&utm_term=&utm_content=Integrated Circuits&productid=6244653&gclid=Cj0KCQjwxveXBhDDARIsAI0Q0x0bm7vRVmrWIk9gyUGJB0QC72wkXo1zohsKKbOU9MIODdXZ-8pNwaMaAgtHEALw_wcB

I base that of the board with the code on it "U1C2" and that pointed me to the chip for the link I posted just now.

I will keep searching but based on what you said it is a power on off chip.

Thanks
Sigma
It is definitely not U1C2.
U1 is the IC designator.
C2 is the circuit designator for the capacitor beside it.
 

Thread Starter

usagoal

Joined Nov 26, 2020
5
Thanks everyone for the replies. The Torex part looks very promising so I will give it a try. MrChips - Out of curiosity, how did you find this regulator?

I will post again to let everyone know if it has been repaired. I appreciate what this site and it's members do. I've also taken some of it's recommendations/tips for identifying other components and applied it to other repairs. Thanks again everyone!
 

Thread Starter

usagoal

Joined Nov 26, 2020
5
Just as a final update: I ordered the correct part from mouser and the board/battery pack now functions as normal! Thanks to everyone for the advice and help through this repair.
 
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