I recently discovered a small stock of Revision 1 of my popular ADC/VMS HAT for Raspberry Pi. This is a fantastic HAT for measuring voltages up to 14.5VDC with your Raspberry Pi. It is perfect for monitoring power supply/battery voltages for high-power projects such as robotics or 3D printers.

There are some limitations to this HAT when compared to the latest revision found HERE but they don't limit the usefulness of the HAT.

LIMITATIONS:

• 5V Terminal is limited to 500ma input/output current
• 3.3v Terminal is limited to 350ma output current
• No output polyfuse protection so be mindful of the current draw of any devices connected to the 5V and 3.3V terminals
• No bypass jumpers to disable the voltage dividers on ADC channels 0-3
• No power LED

VMS Stand for Voltage Measurement System. This HAT is designed to allow measurement of voltages up to 14.5Vdv on channel 0-3. ADC channels 4-7 can measure voltage up to 5Vdc.

I designed this ADC HAT because I couldn't find one on the market that met my needs. I was building a high-powered robot and needed to be able to accurately measure voltages and take analog sensor readings. The Raspberry Pi is notoriously lacking ADC capabilities and this board fills that gap.

Based on the MCP3008 ADC controller IC:

• 16-pin DIP package.
• 8-Channel
• 200 ksps max. sampling rate at VDD = 5V
• 10-Bits of resolution (when powered with 5V.)
• Analog inputs programmable as single-ended or pseudo-differential pairs
• On-chip sample and hold
• SPI serial interface (modes 0,0 and 1,1)
• Low power CMOS technology
• 5 nA typical standby current, 2 µA max.
• 500 µA max. active current at 5V
• Industrial temp range: -40°C to +85°C
• Adafruit Tutorial

Board Features:

• 8 ADC input Channels
• 4-channels configured with voltage divider to allow measuring voltage up to 14.5VDC.
• 4-channels configured for direct-input for ADC measurements up to 5Vdc
• All channels can be used in single-ended or differential mode, allowing for measurements of +/-5Vdc (+/-14.5Vdc on channels 0-3 with voltage-dividers in-line)
• High-quality screw-terminals on all channels (COLOR MAY VARY)
• Hardware or Software SPI, selectable via jumpers.
• Hardware SPI can use CEO of CE1, selectable via solder jumper.
• EEPROM and supporting passive components to allow you to turn into true rPI HAT
• Can stack up to 3 ADC boards per Raspberry Pi by using both hardware SPI inputs and software SPI.

This HAT comes fully assembled with a stacking header.