CAT4237
High
Voltage CMOS Boost
White LED Driver
Description
The CAT4237 is a DC/DC step−up converter that delivers an accurate constant current ideal for driving LEDs.
Operation at a constant switching frequency of 1 MHz allows the device to be used with small value external ceramic
capacitors and inductor.
LEDs connected in series are driven with a regulated current set by the external resistor R1.
LED currents up to 40 mA can be supported over a wide range of input supply
voltages from 2.
8 V to 5.
5 V, making the device ideal for battery−powered applications.
The CAT4237 high−
voltage output stage is perfect for driving six, seven or eight white LEDs in series with inherent current matchin...