LTC1144

Features n Wide Operating Supply Voltage Range: 2V to 18V n Boost Pin (Pin 1) for Higher Switching Frequency n Simple Conversion of 15V to –15V Supply n Low Output Resistance: 120Ω Maximum n Power Shutdown to 8µA with SHDN Pin n Open Circuit Voltage Conversion Efficiency: 99.9% Typical n Power Conversion Efficiency: 93% Typical n Easy to Use Applications n Conversion of 15V to ±15V Supplies n Inexpensive Negative Supplies n Data Acquisition Systems n High Voltage Upgrade to LTC1044 or 7660 n Voltage Division and Multiplications n Automotive Applications n Battery Systems with Wall Adapter/Charger LTC1144 Switched-Capacitor Wide Input Range Voltage Converter with Shutdown Description The LTC®1144 is a monolithic CMOS switched-capacitor voltage converter. It performs supply voltage conversion from positive to negative from an input range of 2V to 18V, resulting in complementary output voltages of –2V to –18V. Only two noncritical external capacitors are needed for the charge pump and charge reservoir functions. The converter has an internal oscillator that can be overdriven by an external clock or slowed down when connected to a capacitor. The oscillator runs at a 10kHz frequency when unloaded. A higher frequency outside the audio band can also be obtained if the Boost Pin is tied to V+. The SHDN pin reduces supply current to 8µA and can be used to save power when the converter is not in use. The LTC1144 contains an internal oscillator, divide-by- two, voltage l...