A 0.9 V 5 MS/s CMOS D/A converter with multi-input floating-gate MOS

An ultra low voltage, low power CMOS D/A converter using a simple multi-input floating-gate MOSFET to perform the dual function of current source and current switch is described. The outcome of this approach is very low supply voltage operation and yet maintaining high conversion accuracy. An experimental 6-bit D/A converter has been fabricated in a standard 1.2 /spl mu/m CMOS technology with V/sub th//spl ap/0.9 V and occupies 0.63 mm/sup 2/ active area. Measurement shows a single 0.9 V supply is sufficient to operate this converter, with less than 0.46 LSB linearity error, 5 MS/s conversion rate and 320 /spl mu/W power dissipation.