Does any board provide more than 1024 analog input values?

Question

The Arduino boards provide an analog input range of 0V to 5V which translates to 0 to 1023 integer values. The range is determined by the on-board ADC, which in the case of the Uno is a 10 bit ADC (2^10 = 1024).

Do any of the official boards have a larger (>10 bits) ADC? Do any boards provide a wider range of analog input values?

• user278: why do you need more bits of resolution specifically?

Answer 1

AVR-based Arduinos only have 10-bit ADCs, but the ATSAM3X in the Due has 12-bit ADCs. Additionally, it is possible to interface to higher-resolution external ADCs via I²C or SPI.

• jippie: Remember that more bits imply higher sensitivity to power supply various other sources of noise.
• jfpoilpret: Could you please provide some references of external ADC chips that connect through I2C or SPI?
• Ignacio Vazquez-Abrams: @jfpoilpret:ti.com/lsds/ti/data-converters/… microchip.com/ParamChartSearch/… parametric.linear.com/… analog.com/parametricsearch/en/…
• Michael Goldshteyn: @jippie, remember that multi-sampling is always available for ADC chips that don't lock in their value...

Answer 2

How much accuracy do you really need? If it's just 1 or 2 extra bits of resolution you are after, you might be able to achieve that with a bit of oversampling.

Basically, you take a ton of readings and average them. It only works if there is at least a few mV of random noise in your signal or in your ADC, and if your input signal bandwidth is low enough to be averaging samples together.

Otherwise, go with a dedicated ADC chip.

Answer 3

They all do with oversampling. You can evaluate the quality of doing this for your own use.

• Anonymous Penguin: Welcome to Arduino SE! Can you please add to your post to explain how you do this? Thanks!