XR16M890 8-bit UART

Exar's XR16M890¹ (M890) is a single-channel universal asynchronous receiver and transmitter (UART) with integrated level shifters and 128 bytes of transmit and receive FIFOs. For flexibility in a mixed voltage environment, the M890 has four VCC pins. There is a VCC pin for the core, a VCC pin for the UART signals, a VCC pin for the CPU interface signals and a VCC pin for the GPIO signals. The VCC pins for the UART, GPIO and CPU interface signals allow for the M890 to interface with devices operating at different voltage levels eliminating the need for external voltage level shifters. The VCC core voltage helps to lower the overall power consumption for applications that use slower data rates.