AD7225

a FEATURES Four 8-Bit DACs with Output Amplifiers Separate Reference Input for Each DAC ␮P Compatible with Double-Buffered Inputs Simultaneous Update of All Four Outputs Operates with Single or Dual Supplies Extended Temperature Range Operation No User Trims Required Skinny 24-Pin DIP, SOIC and 28-Terminal Surface Mount Packages LC2MOS Quad 8-Bit DAC with Separate Reference Inputs AD7225 FUNCTIONAL BLOCK DIAGRAM GENERAL DESCRIPTION The AD7225 contains four 8-bit voltage output digital-toanalog converters, with output buffer amplifiers and interface logic on a single monolithic chip. Each D/A converter has a separate reference input terminal. No external trims are required to achieve full specified performance for the part. The double-buffered interface logic consists of two 8-bit registers per channel–an input register and a DAC register. Control inputs A0 and A1 determine which input register is loaded when WR goes low. Only the data held in the DAC registers determines the analog outputs of the converters. The doublebuffering allows simultaneous update of all four outputs under control of LDAC. All logic inputs are TTL and CMOS (5 V) level compatible and the control logic is speed compatible with most 8-bit microprocessors. Specified performance is guaranteed for input reference voltages from +2 V to +12.5 V when using dual supplies. The part is also specified for single supply operation using a reference of +10 V. Each output buffer amplifier is capable of developing +1...