LM2621

LM2621 Low Input Voltage, Step-Up DC-DC Converter February 2000 LM2621 Low Input Voltage, Step-Up DC-DC Converter General Description The LM2621 is a high efficiency, step-up DC-DC switching regulator for battery-powered and low input voltage systems. It accepts an input voltage between 1.2V and 14V and converts it into a regulated output voltage. The output voltage can be adjusted between 1.24V and 14V. It has an internal 0.17Ω N-Channel MOSFET power switch. Efficiencies up to 90% are achievable using the LM2621. The high switching frequency (adjustable up to 2MHz) of the LM2621 allows for tiny surface mount inductors and capacitors. Because of the unique constant-duty-cycle gated oscillator topology very high efficiencies are realized over a wide load range. The supply current is reduced to 80µA because of the BiCMOS process technology. In the shutdown mode, the supply current is less than 2.5µA. The LM2621 is available in a Mini-SO-8 package. This package uses half the board area of a standard 8-pin SO and has a height of just 1.09 mm. Features n Small Mini-SO8 Package (Half the Footprint of Standard 8-Pin SO Package) n 1.09 mm Package Height n Up to 2 MHz Switching Frequency n 1.2V to 14V Input Voltage n 1.24V - 14V Adjustable Output Voltage n Up to 1A Load Current n 0.17 Ω Internal MOSFET n Up to 90% Regulator Efficiency n 80 µA Typical Operating Current n < 2.5µA Guaranteed Supply Current In Shutdown Applications n n n n n n n n n n PDAs, Cellular Phones 2-Cell and ...