Thermometer code

Thermometer code, or base one, is numerical base system named because it works similarly to a thermometer. Normal finger counting is an example of thermometer code. The fingers add up to the number counted, the way the filled-in part of a thermometer adds up to the temperature reading. It is used in some high-speed digital-to-analog converters in which there is one digital level for each possible output code (e.g. 256 levels for 8-bits) and for a given analog input all digital levels below the input value are 1 and all above are 0.