The MCP1256, MCP1257, MCP1258 and MCP1259 are inductorless, positive regulated charge pump DC/ DC converters. The devices generate a regulated 3.3V output voltage from a 1.8V to 3.6V input. The devices are specifically designed for applications operating from 2-cell alkaline, Ni-Cd, or Ni-MH batteries or by one primary lithium MnO2 (or similar) coin cell battery. The MCP1256, MCP1257, MCP1258 and MCP1259 provide high efficiency by automatically switching between 1.5x and 2x boost operation. In addition, at light output loads, the MCP1256 and MCP1257 can be placed in a SLEEP mode lowering the quiescent current while maintaining the regulated output voltage. Alternatively, the MCP1258 and MCP1259 provide a bypass feature connecting the input voltage to the output. This allows for real-time clocks, microcontrollers or other system devices to remain biased with virtually no current being consumed by the MCP1258 or MCP1259.
