
Analog Devices
GENERAL DESCRIPTION
The 12-channel AD8802/AD8804 provides independent digitally controllable voltage outputs in a compact 20-lead package. This potentiometer divider TrimDAC® allows replacement of the mechanical trimmer function in new designs. The AD8802/AD8804 is ideal for dc voltage adjustment applications.
Easily programmed by serial interfaced microcontroller ports, the AD8802 with its midscale preset is ideal for potentiometer replacement where adjustments start at a nominal value. Applications such as gain control of video amplifiers, voltage controlled frequencies and bandwidths in video equipment, geometric correction and automatic adjustment in CRT computer graphic displays are a few of the many applications ideally suited for these parts. The AD8804 provides independent control of both the top and bottom end of the potentiometer divider allowing a separate zero-scale voltage setting determined by the VREFL pin. This is helpful for maximizing the resolution of devices with a limited allowable voltage control range.
FEATURES
Low Cost
Replaces 12 Potentiometers
Individually Programmable Outputs
3-Wire SPI Compatible Serial Input
Power Shutdown <55 mWatts Including IDD & IREF
Midscale Preset, AD8802
Separate VREFL Range Setting, AD8804
+3 V to +5 V Single Supply Operation
APPLICATIONS
Automatic Adjustment
Trimmer Replacement
Video and Audio Equipment Gain and Offset Adjustment
Portable and Battery Operated Equipment