What kind of chip could this be?
Pin4 is GND, Pin10 Is VCC 3.3v.
Pins 2 and 8 controls 2 led controls 2 LEDs connected in opposite parallel RED and IRED.
On pins 5 and 6 I see identical control pulses in anti-phase.
PCB is Spo2 OEM Module.
Thanks in advance
I have two modules, one of which is broken, and I want to try to fix it.
On the working module, the pulses on pins 3 and 7 are strangely shaped, see the picture.
It’s likely some kind of SPDT, multiplexer, or switch, but the wiring is unclear and doesn’t match the common types of these devices.
I looked at many chips, but couldn’t find a single one with a suitable pinout. It’s especially strange that the 10-pin package has GND on Pin4 and VCC on Pin10, but that’s definitely correct.
Correction!
Signals to pins 3 and 7 come from DAC0 and DAC1 of the ADuC7021.
Hello irakli, welcome to the TechForum! This seems to be some kind of customized ASIC (application specific IC) LED driver used in a pulse oximeter based on some preliminary research. I can’t quite verify who the manufacturer is, though. The issue is that we may not have a match to this unique layout.
I think I found the answer on another forum - it is TLV2463 in a DGS package. It’s not a SPDT, but a dual opamp. It switches diodes and controls their current.
This explains the circuit’s operating principle.
That does appear to match. We do have this in our catalog: 296-7565-5-ND . It does appear to have the same pinout.
