The NCN5151 is a single-chip integrated slave transceiver for use in 2-wire Meter Bus (M-BUS) slave devices and repeaters. The NCN5151 reuses the NCN5150 features and adds two lowpower modes: a 2-wire low power mode dedicated to System for meter Communication and Readout for powerless meters (SCR) and a 3-wire low power mode allowing support for wireless applications. When configured in low power mode, the transceiver will not behave anymore as a constant current source in order to save energy. When configured and used in M-BUS mode, the NCN5151 transceiver provides all of the functions needed to satisfy the European Standards EN 13757-2 and EN 1434-3 describing the physical layer requirements for M-BUS. It includes a programmable power level of up to 6 unit loads, which are available for use in external circuits through a 3.3 V LDO regulator.