IC, WHITE LED DRIVER, BOOST, TSOT-23-5; LED Driver Application:Color LCD and Keypad Backlighting, Digital Cameras; Topology:Boost (Step Up); No. of Outputs:1; Output Current:31.5mA; Output Voltage:30V; Input Voltage:2.8V to 5.5V
LED Driver IC; Device Type:LED; Display Interface:7-segment numeric LED digits, bar graph, or discrete LEDs; Supply Voltage Min:2.8V; Supply Voltage Max:5.5V; Termination Type:SMD; Package/Case:5-TSOT-23; No. of Pins:5 ;RoHS Compliant: Yes
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 1MHz 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 40mA can be supported over a wide range of input supply voltages from 2.8V to 5.5V 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 matching in LCD backlight applications. LED dimming can be done by using a DC voltage a logic signal or a pulse width modulation (PWM) signal. The shutdown input pin allows the device to be placed in power-down mode with zero quiescent current. In addition to thermal protection and overload current limiting the device also enters a very low power operating mode during Open LED fault conditions. The device is housed in a low profile (1mm max height) 5-lead thin SOT23 package for space critical applications.