TT056: Weitz TEC controller

TipTop 1590BB base with a ToprTECDrvr and ToprRTDADC.  TECDrvr is a current source bridge, so it can drive a string of TECs in either direction, up to 2A with a compliance voltage of around 12V with a 15V power supply.

Pics:

Schematics of ToprRTDADC:

Schematics of ToprTECDrvr:

I originally used the QuickPID library, but a recent update broke something, so I went with the canonical Arduino PID.