Atmel® SAM L21 includes three on-chip operational amplifiers. The Operational Amplifier Controller (OPAMP) module offers most common inverting and non-inverting programmable gain and hysteresis configurations. Each OPAMP is software configurable and can be used as a standalone general purpose operational amplifier. This application note introduces the configuration and usage of the OPAMP module, different built-in modes, and also presents an application example. In the application example, one of the operational amplifiers is configured as a non-inverting gain amplifier with output internally connected to ADC. With this setup, the OPAMP operates as a gain amplifier stage for ADC sampling.
