LM2681 Datasheet | National Semiconductor

Description The LM2681 CMOS charge-pump voltage converter operates as a voltage doubler for an input voltage in the range of +2.5V to +5.5V. Two low cost capacitors and a diode (needed during start-up) is used in this circuit to provide up to 20 m A of output current. The LM2681 can also work as a voltage divider to split a voltage in the range of +1.8V to +11V in half. The LM2681 operates at 160 k Hz oscillator frequency to reduce output resistance and voltage ripple. With an operating current of only 550 µA (operating efficiency greater than 90% with most loads) the LM2681 provides ideal performance for battery powered systems. The device is in SOT-23-6 package. Features n n n n Doubles or Splits Input Supply Voltage SOT23-6 Package 15Ω Typical Output Impedance 90% Typical Conversion Efficiency at 20 m A Applications n n n n n n Cellular Phones Pagers PDAs Operational Amplifier Power Suppliers Interface Power Suppliers Handheld Instruments Basic Application Circuits Voltage Doubler DS100965-1 Splitting Vin in Half DS100965-2 © 1999 National Semiconductor Corporation DS100965 .national. Absolute Maximum Ratings (Note 1) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage (V+ to GND, or GND to OUT) V+ and OUT Continuous Output Current Output Short-Circuit Duration to GND (Note 2) Continuous Power Dissipation (TA = 25˚C)(Note 3) 5.8V 30 m A 1 sec. 600 m W TJMax(Note 3) θJA (Note 3) Operating Junction Temperature Range Storage Temperature Range Lead Temp. (Soldering, 10 seconds) ESD Rating 150˚C 210˚C/W - 40˚ to 85˚C - 65˚C to +150˚C 300˚C 2k V Electrical Characteristics Limits in standard typeface are for TJ = 25˚C, and limits in boldface type apply over the full operating temperature range. Unless otherwise specified: V+ = 5V, C1 = C2 = 3.3 µF. (Note 4) Symbol V+ IQ IL RSW ROUT f OSC f SW PEFF Parameter Supply Voltage Supply Current Output...