Identifying an MCU by the pin-out

Thread Starter

teelo

Joined Apr 1, 2011
1
I bought a cheap RGB light strip from China that came with a little controller box and a remote. The remote was broken from the get-go, but the little controller works fine.

inside is an unknown chip that might be a MCU, a 24C02 serial EEPROM and three transistors to PWM switch the LED channels for the RGB light strip.

Now, it would be easy enough to just remove the existing MCU and replace it with a little PIC to do my bidding, but I am wondering if the chip that's already on the board could be re-programmed.

Unfortunately there are no markings on the chip whatsoever (apart from the "pin 1" dot). I was thinking maybe it can be identified by the pin-out.
It's a 14 pin SOIC device.

NC 1 14 IR remote IN
NC 2 13 EEPROM Pin 6 SCL
NC 3 12 EEPROM Pin 5 SDA
Vcc 4 11 GND
Bttn 5 10 LED Channel Out 1
NC 6 9 LED Channel Out 2
NC 7 8 LED Channel Out 3

I already looked around online but could not find any MCU that would match, especially the Pin 4 / Pin 11 Vcc / GND pairing I thought would be somewhat unique. And I don't know if the I2C bus is bit-banged or if it's actually implemented on the chip itself.
Pin 5 is a mode selector button that goes against GND when pressed, it cycles the MCU (?) through various lighting / color / flashing modes for the RGB strip.

So, I hope this was not too long, I wanted to be thorough. :) What do you guys think? Any idea what this could be? Thanks!
 

Papabravo

Joined Feb 24, 2006
21,225
The real answer is "not likely". The most likely explanation is that it is a custom job with a proprietary in house design and "no markings" on purpose.
 

t06afre

Joined May 11, 2009
5,934
If it is a MCU. The code will most probably be protected. So you can not read the code out of the MCU. And hence copy it..
 
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