The AD7542 is a precision 12-bit CMOS multiplication DAC designed for direct interface with 4- or 8-bit microprocessors.
The functional block diagram shows that the AD7542 includes three 4-bit data registers, a 12-bit DAC register, address decoding logic, and a 12-bit CMOS multiplication DAC. The data is loaded into the data register in three 4-bit bytes and then transferred to the 12-bit DAC register. All data loading or data transfer operations are the same as WRITE cycles for static RAM. When the device is powered on, the DAC register can be easily reset to full zero using the zeroing input.