This Hat has been renamed as "10-Bit ADC/VMS Hat" due to recent redesign

A 12-channel version of this board with both 10 and 12-bit resolution, without VMS resistors is available here:10+12-bit ADC Pi Hat

VMS Stand for Voltage Measurement System. This version of the board is designed to allow measurement of voltages up to 14.5Vdv on channel 0-3. Version 2.1 of this board is now available. If you order today, you will get the new version.

Features of version 2.1:

• Power LED
• Soft-Fuse protection on 5V output (PTC, self-healing) for Raspberry PI
• Input filter caps on 5V input
• Solder-jumpers on ports 0-3 to disable voltage dividers*
• • results in weak 4.7K pull-down to GND on channel which should not affect measurements
• Improved board layout with additional GND connections available
• Increased trace sizes on power rails
• Updated silkscreen

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.
• Voltage dividers can be disabled via solder jumper.
• 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)

Features

• Power LED
• 3.3V, 5V, and GND connection terminals.
• Input filtering for improved stability
• Board can back-power Raspberry Pi via 5V and GND connection terminals.
• PTC soft-fuse on 5V power tap to protect Raspberry Pi from overcurrent
• High-quality screw-terminals on all channels.
• Hardware or Software SPI, selectable via jumpers.
• Hardware SPI can use CEO of CE1, selectable via solder jumper.
• Footprint for EEPROM and supporting passive components to allow you to turn into true rPI HAT (EEPROM and passives optional.)
• Stackable header option.
• Can stack up to 3 ADC boards per Raspberry Pi by using both hardware SPI inputs and software SPI.

NOTE: This board ships with all headers un-soldered. Some light soldering is required to connect the headers and connectors. You can optionally elect to have the board shipped to you complete assembled for a nominal fee by selecting the option on the right.

All SMD components are pre-assembled, including the EEPROM and related passive components if you select to add them, regardless of the options selected.