AD7801

a FEATURES Single 8-Bit DAC 20-Pin SOIC/TSSOP Package +2.7 V to +5.5 V Operation Internal and External Reference Capability DAC Power-Down Function Parallel Interface On-Chip Output Buffer Rail-to-Rail Operation Low Power Operation 1.75 mA max @ 3.3 V Power-Down to 1 ␮ A max @ 25؇ C APPLICATIONS Portable Battery Powered Instruments Digital Gain and Offset Adjustment Programmable Voltage and Current Sources Programmable Attenuators +2.7 V to +5.5 V, Parallel Input, Voltage Output 8-Bit DAC AD7801 FUNCTIONAL BLOCK DIAGRAM D7 D0 INPUT REGISTER DAC REGISTER I DAC I/V VOUT WR CS CONTROL LOGIC MUX POWER-ON RESET AD7801 PD CLR LDAC REFIN ÷2 AGND VDD DGND GENERAL DESCRIPTION PRODUCT HIGHLIGHTS The AD7801 is a single, 8-bit, voltage out DAC that operates from a single +2.7 V to +5.5 V supply. Its on-chip precision output buffer allows the DAC output to swing rail to rail. The AD7801 has a parallel microprocessor and DSP compatible interface with high speed registers and double buffered interface logic. Data is loaded to the input register on the rising edge of CS or WR. Reference selection for the AD7801 can be either an internal reference derived from the VDD or an external reference applied at the REFIN pin. The output of the DAC can be cleared by using the asynchronous CLR input. The low power consumption of this part makes it ideally suited to portable battery operated equipment. The power consumption is less than 5 mW at 3.3 V, reducing to less than 3 µW in power-dow...