LM2664

Switched Capacitor Voltage Converter

General Description

The LM2664 CMOS charge-pump voltage converter inverts

a positive voltage in the range of +1.8V to +5.5V to the

corresponding negative voltage of −1.8V to −5.5V. The

LM2664 uses two low cost capacitors to provide up to 40 mA

of output current.

The LM2664 operates at 160 kHz oscillator frequency to

reduce output resistance and voltage ripple. With an operat-

ing current of only 220 µA (operating efficiency greater than

91% with most loads) and 1 µA typical shutdown current, the

LM2664 provides ideal performance for battery powered

systems. The device is in SOT-23-6 package.

Features

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Inverts Input Supply Voltage

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SOT23-6 Package

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12

Ω Typical Output Impedance

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91% Typical Conversion Efficiency at 40 mA

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1µA Typical Shutdown Current

Applications

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Cellular Phones

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Pagers

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PDAs

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Operational Amplifier Power Suppliers

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Interface Power Suppliers

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Handheld Instruments

Basic Application Circuits

Voltage Inverter

10003101

+5V to −10V Converter

10003125

September 2005

© 2005 National Semiconductor Corporation

DS100031

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