Need Help identifying IC

Thread Starter

prosound3

Joined Apr 10, 2021
3
Am attempting to repair an automotive wireless phone charger, which has a burnt IC. Appears to be a power management device, with direct input from 12VDC source on pin#2. One section of the top is burnt, which has obscured some of the markings. Has a large U logo. 4 pins, SOIC pkg.
First line marked 034B1 (unsure of first two characters, 3 could be an 8, and 0 could be top of a 2 or 3).
Second line has 3476 as ending characters, prefix is missing. Suspect that this is a V reg or PWM controller of some sort.
 

MrSalts

Joined Apr 2, 2020
523
Measure the coil resistance They normally fail when the enamel on the coil wire fails and causes a short - most of the cheap wireless chargers were automotive vibration tested my the manufacturer and that was a mistake. In other words, the chip failed for a reason and replacing the chip doesn’t change anything.
 

Thread Starter

prosound3

Joined Apr 10, 2021
3
Measure the coil resistance They normally fail when the enamel on the coil wire fails and causes a short - most of the cheap wireless chargers were automotive vibration tested my the manufacturer and that was a mistake. In other words, the chip failed for a reason and replacing the chip doesn’t change anything.
This is actually new, but not warranted for reasons I won't go into here. Worth a shot to try, if I can find the correct part. The DCR of the 3 coils is extremely low (less than 1 Ohm). The inductance is 6-7 uH, and they all ring 11-15 times, so it appears that the coils are all good. The unit tried to work for a short time, with output in the 350kHZ range, but low output, but then died.
 

Thread Starter

prosound3

Joined Apr 10, 2021
3
Am attempting to repair an automotive wireless phone charger, which has a burnt IC. Appears to be a power management device, with direct input from 12VDC source on pin#2. One section of the top is burnt, which has obscured some of the markings. Has a large U logo. 4 pins, SOIC pkg.
First line marked 034B1 (unsure of first two characters, 3 could be an 8, and 0 could be top of a 2 or 3).
Second line has 3476 as ending characters, prefix is missing. Suspect that this is a V reg or PWM controller of some sort.
Whoops--IC has 8 pins (4 on a side). Checking further, the unit will operate if +5VDC is applied to the output pin (#3).
 
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