The DAC-8228 is a single-chip, dual-channel, 8-bit voltage output CMOS D/A converter. Designed to fit into the AD7528/7628 socket, eliminating the need for two external op-amps in applications such as hard drives. Typically, these applications drive the AD7528/7628 at zero volts applied to the VREF and bias the AGND to +2.5V or +5V. The DAC-8228 has been tested under these conditions.
The DAC-8228 can also be used in applications requiring a unipolar output voltage. The output voltage range is 0V to +10V, VDD=+14V (maximum output voltage is VDD-4V). The reference input of the DAC-8228 can accept negative voltages from 0V to -10V (the DAC's internal unity-gain inverting amplifier inverts the input signal). For bipolar applications, choose the DAC-8229.
DAC8228 is available in CerDIP and molded packages with an operating temperature range of -40° to +85°C for extended industrial temperature ranges. Applications that require military temperature ranges to use DAC-8229 are required. In order for the DAC-8229 to be pin-to-pin and functionally compatible with the DAC-8228, AGND A and AGND B should be connected together to act as a VZ and the VSS to GND.
The DAC-8228 consists of two CMOS voltage output amplifiers, two high-precision R-2R resistor ladder networks, interface control logic, and two 8-bit registers. An internal regulator maintains TTL logic compatibility and fast microprocessor interface timing performance across the VDD range.
The DAC-8228 consumes only 90mW and is available in a 20-pin 0.3" DIP package or a 20-pin SO surface-mount package for space savings. Its small size, low power consumption, and low cost per channel make it ideal for applications with multiple D/A converters without sacrificing board space. The reduced number of components also helps to improve system reliability.
Utilizing PMI's advanced oxide isolation, silicon gate CMOS process, and highly stable thin-film resistor trapezoidal network, the DAC-8228 provides excellent DAC-to-DAC matching and temperature tracking capabilities.