[SOLVED] please tell me what is this ic?

[adnan_merter]

hi guys i am trying to create some optical communication interface using some ir leds and photo diodes, so far nothing much but
i found a device and trying a little bit reverse engineering. it uses max3380 to level shifting and inverting, and a photodiode and ir led to communicate the other device. i draw a schematic from this device but i couldnt figure out the ic, it is in smd form and no id on it. i thought it would be a schmitt trigger ic but i think i am wrong. please tell me what it could be or any other ic that can do the same job. thanks.

 

[hexreader]

Looks like something from the PIC10F series of microcontrollers to me.

....But there is something not quite right about your schematic. Are you sure you drew it correctly?

 

[adnan_merter]

Looks like something from the PIC10F series of microcontrollers to me.

....But there is something not quite right about your schematic. Are you sure you drew it correctly?

it is not an mcu it is something like darlington array or schmit trigger or any analog ic, there is no need for mcu. my schematic is correct i checked twice.is there any other ic to drive the led and photodiode?

 

[hexreader]

Ah... I think I see the mistake in the schematic....

I suspect that the LED symbol is actually the photo-diode and the photo-diode symbol is the LED.

 

[adnan_merter]

Ah... I think I see the mistake in the schematic....

I suspect that the LED symbol is actually the photo-diode and the photo-diode symbol is the LED.

yes you are right, the colors of led and photo-transistor confused me, normally the receiving part must be dark colored for daylight protection but in this device LED is darker. strange, so it was all figured out, the ic must be dual schmitt trigger. thanks for your help.

 

[Analog Ground]

I see this post is marked as "solved" but let me add some more info. The pinout, 3.3V power and functionality match parts from TI such as the SN74AUP2G04 or similar. These are a series of low gate count, logic ICs.

 

[adnan_merter]

I see this post is marked as "solved" but let me add some more info. The pinout, 3.3V power and functionality match parts from TI such as the SN74AUP2G04 or similar. These are a series of low gate count, logic ICs.

there is no need for inverting, the signal is already inverted by max3380, i think it is something like 74LVC2G17 or similar ic. i searched on the net schmitt trigger is needed to increase reliability for long distance communication. thanx for reply.

 

[Analog Ground]

Thank you for closing the loop on your post. I did not work out the details and only wanted to give you a pointer to likely candidates. A Schmitt trigger input is definitely the way to go.