The PicoADC16 is a 16-port ADC board with screw terminals using two 8-port MCP3008 10-bit Analogue to Digital converters connected to the Raspberry Pi Pico using a SPI interface.

Can be used with voltages higher that 3.3V when resistors (not-supplied) are soldered onto the board.

The two MCP3008 ADC IC are banked A0-A7 (set chip enable "SPI CE A" low) and B0-B7 (set chip enable "SPI CE B" low). On each side of the board there are 10 screw terminals "GND, A0, A1, A2, A3, A4, A5, A6, A7, GND" and "GND, B0, B1, B2, B3, B4, B5, B6, B7, GND".

The maximum input voltage for the ADC is 3.3 Volts.

Resistor Divider (when measuring voltages greater than 3.3 Volts)

Each of the 16 ADC inputs has the option to use two through hole resistors (RxxL and RxxH) to create a voltage divider.

The formula to calculate the voltage at the ADC is "Vadc = RxxL / ( RxxH + RxxL ) * Vscrew". When using the voltage divider cut the appropriate solder jumper on the bottom of the board for that port (e.g. for port B4 you would populate resistors RB4H and RB4L and cut the B4 trace on the underside of the board).

For example to measure up to 60 volts DC you could use a 2.7k resistor for RxxH and 47K resistor for RxxL (care must be taken when using with high voltages).

2700 / ( 2700 + 47000 ) * 60 = 3.25955 which is below the 3.3 Volt maximum input for the ADC.

NOTICE: After populating the resistors and cutting the solder jumper I strongly advise testing with a 3.3 Volt maximum input to ensure the solder jumper has been cut properly as connecting a high voltage to the input may damage the PicoADC16 and/or Pico.

An optional clear acrylic shield is available which protects the top/bottom of the board from shorts whilst still allowing the screw terminals to be accessed.