The AD7628 is an AD company's 8-bit digital-to-analog converter with excellent DAC-to-DAC matching. It uses a small 0.3-inch wide 20-pin DIP and 20-pin surface mount package. Each DAC has a separate on-chip latch to allow easy microprocessor interface. Data is transferred to either of the two DAC data latches through a common 8-bit TTL/CMOS compatible input port. The control input DAC A/DAC B determines which DAC is to be loaded. The AD7628's load cycle is similar to the write cycle of a random access memory, and the device is bus compatible with most 8-bit microprocessors, including 6502, 6809, 8085, Z80. The device operates from a +12 V to +15 V power supply and is TTL-compatible over this range. Power dissipation is a low 20 mW. Both DACs offer excellent four quadrant multiplication characteristics with a separate reference input and feedback resistor for each DAC.
The AD7628 is a monolithic dual 8‑bit CMOS multiplying DAC featuring on‑chip latches, four‑quadrant multiplication, and TTL/CMOS compatible inputs. It is offered in 20‑pin DIP, SOIC, PLCC and LCC packages and operates from a single supply voltage.
The document provides full electrical specifications, absolute maximum ratings, pin‑out diagrams, timing information, and example application circuits such as single‑supply operation, microprocessor interfaces, programmable window comparators, and a dual telephone attenuator.
| Resolution | 8 Bits |
|---|---|
| Relative Accuracy | ±4½ LSB max |
| Differential Nonlinearity | ±1 LSB max |
| Gain Error (K grade) | +2 LSB max |
| Input High Voltage (TTL compatible) | 2.4 V min |
| Output Leakage Current (OUT A) | +50 nA max |
| Power Dissipation | 20 mW |
The AD7628 can be operated with any supply voltage in the range 10.8 V to 15.75 V, and it is also specified to work from a +12 V to +15 V power supply.
The AD7628 provides 8‑bit resolution for each of its two DAC channels.
The maximum output leakage current for OUT B (Pin 20) is +200 nA.