GENERAL DESCRIPTION

The ML4870 is a continuous conduction boost regulator designed for DC to DC conversion in multiple cell battery power systems. Continuous conduction allows the regulator to maximize output current for a given inductor. The maximum switching frequency can exceed 200kHz, allowing the use of small, low cost inductors. The ML4870 is capable of start-up with input voltages as low as 1.8V, and is available in 5V and 3.3V output versions with an output voltage accuracy of ±3.

FEATURES

■ Guaranteed full load start-up and operation at 1.8V input

■ Continuous conduction mode for high output current

■ Pulse Frequency Modulation and internal synchronous rectification for high efficiency

■ Isolates the load from the input during shutdown

■ Minimum external components

■ Low ON resistance internal switching FETs

■ Low supply current

■ 5V and 3.3V output versions