Need help identifying a circuit board

[kaysadeya]

The circuit board in the attached photo comes from a security camera I bought recently on ebay:

**broken link removed**

Due to an installation error on my part, I damaged the board.

The markings are:

IR Interface-12P V1.2
2014-3

E320003
YF-2 ?? 94V-0
0816e7701

Can anyone identify this board and provide directions on how to obtain a replacement?

 

[Pommie]

I'm guessing that you connected power the wrong way around. If so (and if you're very lucky) then the diode on the left (D9) may have acted as a fuse and may be the only part that needs replacing.

Mike.

 

[kaysadeya]

Thanks Mike. Yes the D9 is crispy, but so is the round diode on the right (R1, I think).

What I think caused this that I wired the RS485 (the wires that control the PTZ features) incorrectly.

 

[Pommie]

If you can identify all the parts it would be trivial to replace them all. Certainly easier than getting a replacement board.

Mike.

 

[kaysadeya]

They're too burnt. I'd need a schematic.

 

[DerStrom8]

Considering the way D9 is connected (one side connected to a fat trace, one connected to what I expect is the ground plane) chances are it's a unidirectional transient voltage suppression diode. If you connected power backwards it would behave as a forward-biased diode with ~0.7V Vf and would fry. I would pop it off the board (desolder the best you can) and measure across the pads with an ohm-meter. If the ohms are significantly low, then you probably have other problems as well. Otherwise you're probably fine. Theoretically if the rest of the board is not damaged, removing this diode would allow it to work again, albeit without transient protection. You could replace the diode with one that has a standoff voltage equal to or slightly greater than the supply voltage. For example this camera appears to run off of 12 volts. Replace the diode with a 12-15V unidirectional TVS diode (Looks like it may be an SMB/DO-214AA or an SMC/DO-214AB package - you'll have to measure to be sure).

SMB version: https://www.digikey.com/product-detail/en/bourns-inc/SMBJ12A/SMBJ12ABCT-ND/2254268
SMC version: https://www.digikey.com/product-detail/en/bourns-inc/SMCJ12A/SMCJ12ABCT-ND/2254118