Description
The CAT661 is a charge−pump voltage converter. It can invert a positive input voltage to a negative output. Only two external capacitors are needed. With a guaranteed 100 mA output current capability, the CAT661 can replace a switching regulator and its inductor. Lower EMI is achieved due to the absence of an inductor.
In addition, the CAT661 can double a voltage supplied from a battery or power supply. Inputs from 2.5 V to 5.5 V will yield a doubled, 5 V to 11 V output.

Features
• Converts V+ to V− or V+ to 2V+
• Low Output Resistance, 10 Ω Max.
• High Power Efficiency
• Selectable Charge Pump Frequency of 25 kHz or 135 kHz; Optimize Capacitor Size
• Low Quiescent Current
• Pin−compatible to MAX660, LTC660 with Higher Frequency Operation
• Available in 8−pin SOIC and DIP Packages
• These Devices are Pb−Free, Halogen Free/BFR Free and are RoHS Compliant

Applications
• Negative Voltage Generator
• Voltage Doubler
• Voltage Splitter
• Low EMI Power Source
• GaAs FET Biasing
• Lithium Battery Power Supply
• Instrumentation
• LCD Contrast Bias
• Cellular Phones, Pagers