GENERAL DESCRIPTION
The device operates at 1 Mbps data rate with worst case 3K ohms load. Both RS-232 driver outputs and receiver inputs can operate in harsh electrical environments of +/-15V without damage and can survive multiple +/-15kV ESD on the RS-232 lines, while maintaining RS-232 output levels. The L212 operates in four different modes: Active, Partial Sleep, Full Sleep and Power-Save. Each mode can be invoked via hardware or software. Upon power-up, the L212 is in the Active mode where the UART and RS-232 transceiver function normally. In the Partial Sleep mode, the internal crystal oscillator of the UART or charge pump of the RS-232 transceiver is turned off. In Full Sleep mode, both the crystal oscillator and the charge pump are turned off. While the UART is in the Sleep mode, the Power-Save mode isolates the core logic from the control signals (chip select, read/write strobes, address and data bus lines) to minimize the power consumption. The RS-232 receivers remain active in any of these four modes.
Exar Corporation
