Solar Shed - Realized

My original plan was to build a perf board proto with the LT1085 and the relays.  Then after some thought I decided  I needed to add multiple ADC inputs.  The PIC ADC does not like high impedance inputs.  I had lots of low bandwidth (<15KHz) OP_AMPS that would provide the buffer and a low impedance input to the ADC.  These MCP6031 are set up as unity gain buffers.  The input is scaled down depending on the input voltage range.  

Well using these SOT-23-5 parts made perf board very hard.  One of the PCB fab houses I use was running a special of $5 (plus shipping) for 4" by 4", qty 5.  Thus it made since to make a PCB.  Easier to build and more reliable.

Here is the board.

 

 

This the board next to the Curiosity HPC Development board.  The daughter board will plug into the connectors on either side of the processor.

 

 

Here is the unpopulated daughter board attached to the Curiosity HPC.

Here is the daughter board assembled. 

These are the major parts of the daughter board.

• LT0185 with 100uf 50VDC capacitors on the input and output. I have lots of these capacitors, so I decide to use them.  They are excessive in size and capacity, but they are free.  The LT085 takes in the solar panel output and generates the 14.4VDC charging voltage.
  
• Two 12 dual latching relays that control connection to the battery and the LED lighting in the shed.
• Some N-FET buffers for the PIC outputs that control the Relays,
• The MCP6031 OP-AMP buffers.
• A LDO that converts battery voltage to 5VDC for the Curiosity HPC.  In turn the Curiosity HPC converts this 5VDC to 3.3VDC.
• The necessary connections to the Solar panel, battery, light switch and LED light power.