Both parts are microprocessor compatible, with high speed data latches and double-buffered interface logic. The AD7245A accepts 12-bit parallel data which is loaded into the input latch on the rising edge of CS or WR. The AD7248A has an 8-bit wide data bus with data loaded to the input latch in two write operations. For both parts, an asynchronous LDAC signal transfers data from the input latch to the DAC latch and updates the analog output. The AD7245A also has a CLR signal on the DAC latch which allows features such as power-on reset to be implemented.
The on-chip 5 V buried Zener diode provides a low noise, temperature compensated reference for the DAC. For single supply operation, two output ranges of 0 V to +5 V and 0 V to +10 V are available, while these two ranges plus an additional ±5 V range are available with dual supplies. The output amplifiers are capable of developing +10 V across a 2 kOhm load to GND.
The AD7245A/AD7248A is fabricated in linear compatible CMOS (LC2MOS), an advanced, mixed technology process that combines precision bipolar circuits with low power CMOS logic. The AD7245A is available in a small, 0.3" wide, 24-pin DIP and SOIC and in 28-terminal surface mount packages. The AD7248A is packaged in a small, 0.3" wide, 20-pin DIP SOIC and in 20-terminal surface mount packages.