MICROPOWER INVERTING DC-DC CONVERTER
January 29, 1998
SC1652
TEL:805-498-2111 FAX:805-498-3804 WEB:http://www.
semtech.
com
DESCRIPTION
The SC1652 is a high performance inverting DC-DC converter, designed to drive an external power switch to generate programmable negative voltages.
In the particularly suitable LCD bias contrast application, efficiency of 87% can be achieved with low cost
PNP bipolar
transistor drivers.
The output voltage can be scaled to -40V by two external resistors.
A pulse frequency modulation scheme is employed to maintain high efficiency conversion under wide input voltage ranges.
Quiescent current is about 80µA and can be reduced to 0.
7µA in shutdown mode.
With a swi...