Switched Capacitor Voltage Converter

The LTC1044 is a monolithic CMOS switched capacitor voltage converter which is manufactured using Analog Devices’ enhanced LTCMOS™ silicon gate process. The LTC1044 provides several voltage conversion functions: the input voltage can be inverted (VOUT = –VIN), doubled (VOUT = 2VIN), divided (VOUT = VIN/2) or multiplied (VOUT = ± nVIN).

Designed to be pin-for-pin and functionally compatible with the popular 7660, the LTC1044 provides significant features and improvements over earlier 7660 designs. These improvements include: full 1.5V to 9V supply operation over the entire operating temperature range, without the need for external protection diodes; two and one-half times lower quiescent current for greater power conversion efficiency; and a “boost” function which is available to raise the internal oscillator frequency to optimize performance in specific applications.

Although the LTC1044 provides significant design and performance advantages over the earlier 7660 device, it still maintains its compatibility with existing 7660 designs.

Applications

* Conversion of 5V to ±5V Supplies

* Precise Voltage Division, VOUT = VIN/2 ±20ppm

* Voltage Multiplication, VOUT = ±nVIN

* Supply Splitter, VOUT = ±VS/2

* Plug-In Compatible with 7660 with These Additional Features:

* Guaranteed Operation to 9V, with No External Diode, Over Full Temperature Range

* Boost Pin (Pin 1) for Higher Switching Frequency

* Lower Quiescent Power

* Efficient Voltage Doubler