SP4438 Datasheet | Sipex

DESCRIPTION The SP4438 device is a low noise, high voltage output DC-AC inverter designed to drive electroluminescent lamps to backlight liquid crystal display and keypads used in cellular phones, cordless phones, 2-way radios, and other wireless munication products. The output waveform of the SP4438 device is ideal for cell phone applications requiring low acoustic noise performance. One external resistor is used to set the internal oscillator frequency and one inductor is required to generate the high voltage AC output to drive an EL lamp up to 3 square inches in size. The SP4438 operates from a +3.0V battery source and has a low power standby mode that draws less than 1µA, making it ideal for low-power cellular applications. All input pins are ESD protected with internal diodes to VDD and VSS. The SP4438 is offered in a space-saving 8-pin MSOP package. VBATT VDD 1 ELEN 2 ROSC 3 VSS 4 SP4438 EL1 ELEN 2 L1 820µH/14Ω 7 EL2 6 5 CINT COIL C1 0.1µF C2 1n F VDD ROSC 714kΩ 1 ROSC 3 4 5 6 COIL D1 1N4148 CINT 8 VSS EL1 7 EL2 CINT 47n F EL Lamp Rev.11/13/00 SP4438 Ultra-Quiet Electroluminescent Lamp Driver © Copyright 2000 Sipex Corporation ABSOLUTE MAXIMUM RATINGS These are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. Supply Voltage (VDD to VSS) -0.3V, +5V Operating Temperature -40˚C to +85˚C Storage Temperature -65˚C to +150˚C Power Dissipation Per Package 8-pin MSOP (derate 4.85m W/OC above +70OC) 400m W SPECIFICATIONS VDD = +2.7V to +3.3V, LCOIL = 820µH/14Ω, ROSC = 714kΩ, EL Lamp Load = (8n F + 2.5kΩ)/1MΩ, and TAMB = -40OC to +85OC. TAMB = 25OC for typical values unless otherwise noted. PARAMETER INPUT CHARACTERISTICS...