19-1095; Rev 2; 12/97
1-Cell to 3-Cell, High-Power, Low-Noise, Step-Up DC-DC Converters
General Description
The MAX848/MAX849 boost converters set a new standard of high efficiency and high integration for noisesensitive power-supply applications, such as portable phones and small systems with RF data links.
The heart of the these devices is a synchronous boost-topology
regulator that generates a fixed 3.
3V output (or 2.
7V to 5.
5V adjustable output) from one to three NiCd/NiMH cells or one Li-Ion cell.
Synchronous rectification provides a 5% efficiency improvement over similar nonsynchronous boost
regulators.
In standby mode, pulse-skipping PFM operation keeps the output voltage alive with ...