Author Topic: Help identify SOT23-5 marked LAD  (Read 4619 times)

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Offline geejaTopic starter

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Help identify SOT23-5 marked LAD
« on: June 01, 2015, 08:52:42 pm »
I'm trying to find the part number for this 5 pin SOT23. It is marked as LAD. I think it's an Analog Devices or TI voltage regulator.
 

Offline mengfei

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Offline geejaTopic starter

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Offline bktemp

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Re: Help identify SOT23-5 marked LAD
« Reply #3 on: June 02, 2015, 02:05:02 pm »
TI has a LADQ marked device:
http://www.ti.com/product/lmv331-q1
 

Offline wraper

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Re: Help identify SOT23-5 marked LAD
« Reply #4 on: June 02, 2015, 02:53:11 pm »
 

Offline geejaTopic starter

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Re: Help identify SOT23-5 marked LAD
« Reply #5 on: June 02, 2015, 03:33:50 pm »
Here's some more info I've measured on a working unit.
pin#
1: 5v
2: GND
3: 3.3v
4,5 : 1.8v
pins 4 and 5 are shorted together which is odd. Seems like a 1.8v voltage regulator with enable but 4 and 5 shouldn't be shorted together.
The marking seems to follow TI or Analog Devices convention, but the TI mark search for LAD turns up no match.
 

Offline bktemp

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Re: Help identify SOT23-5 marked LAD
« Reply #6 on: June 02, 2015, 03:53:04 pm »
The TI marking search gives a a few matches, but only one with SOT23-5, but it is marked LADQ. Therefore it is probably not a TI part.
I tried a few other marking code searches, but all show the same part.

Could it be a voltage supervisor? Then the shorted pins could make sense (disabled external reset input).
Voltage supervisor ics have a different marking for each voltage variant and are therefore rarely listet on marking code sites because a single ic would fill a whole page with all its variants.
 

Offline wraper

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Re: Help identify SOT23-5 marked LAD
« Reply #7 on: June 02, 2015, 03:57:40 pm »
Here's some more info I've measured on a working unit.
pin#
1: 5v
2: GND
3: 3.3v
4,5 : 1.8v
pins 4 and 5 are shorted together which is odd. Seems like a 1.8v voltage regulator with enable but 4 and 5 shouldn't be shorted together.
The marking seems to follow TI or Analog Devices convention, but the TI mark search for LAD turns up no match.
Are you sure that pins 4 and 5 are shorted, not just same voltage? Some regulators have pin 4 as power good output with open drain which is then connected with resistor to Vout. Many regulators have pin 4 as NC, somebody could decide to connect it to Vout for some reason too.
 

Offline geejaTopic starter

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Re: Help identify SOT23-5 marked LAD
« Reply #8 on: June 02, 2015, 05:17:16 pm »
Yes, 4 and 5 definitely shorted together. Measured the board with and without chip installed.
 

Offline bingo600

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Re: Help identify SOT23-5 marked LAD
« Reply #9 on: June 02, 2015, 05:44:29 pm »
These are the ones i have in the smd book




/Bingo
 

Offline geejaTopic starter

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Re: Help identify SOT23-5 marked LAD
« Reply #10 on: June 08, 2015, 08:39:13 pm »
Unfortunately, none of the above looks right, still think it's an Analog Devices part, does anyone have an Analog Devices lookup?
 


Offline c4757p

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Re: Help identify SOT23-5 marked LAD
« Reply #12 on: June 09, 2015, 08:33:45 pm »
still think it's an Analog Devices part

why?
No longer active here - try the IRC channel if you just can't be without me :)
 

Offline geejaTopic starter

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Re: Help identify SOT23-5 marked LAD
« Reply #13 on: June 09, 2015, 10:33:18 pm »
Thanks to everyone that replied. I found it, :)
http://www.analog.com/en/products/power-management/linear-regulators/adp2108.html

I saw that there was an inductor and cap hanging on what should be an output pin 1 and started looking at Analog Devices switching regulators and found it.
 


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