The AD567 is a complete high-speed, 12-bit single-chip digital-to-analog converter with a high-stability embedded Zener reference and a dual-buffered input latch. The converter features 12 precision, high-speed, bipolar current-guide switches and a laser-tuned thin-film resistor network that provides fast settling times and high-precision features.
Microprocessor compatibility is achieved through dual buffer latches on the chip. The input latch is capable of directly interfacing with 4-, 8-, 12-, or 16-bit buses. Therefore, the 12-bit data from the first stage latch can be transferred to the second level of latch to avoid stray analog outputs. The latch responds to short strobe pulses of 100 ns, allowing it to work with the fastest microprocessors available.
The AD567's comprehensive features and high performance are the result of advanced switching design, high-speed bipolar manufacturing process, and proven laser wafer adjustment technology (LWT). The device is tuned at the wafer stage for a maximum linear error of ±1/4 LSB (class K) at 25°C and ±1/2 LSB over the entire operating temperature range.
The chip's subsurface (embedded) Zener diode provides a low-noise reference with long-term stability and temperature drift characteristics comparable to the best discrete voltage references. The laser adjustment process provides excellent linearity and is also used to adjust the absolute value of the reference voltage source and its temperature coefficient. As a result, the AD567 has a wide temperature range performance with a maximum linearity error of ±1/2 LSB and can guarantee monotonicity over the entire temperature range. The typical temperature coefficient of full-scale gain is 10 ppm/°C.
The AD567 is divided into three grades based on performance. The AD567J and AD567K are rated for an operating temperature range of 0°C to +70°C and are available in either a 28-pin sealed ceramic DIP or a 28-pin injection molded DIP package (N package). The AD567S is rated for a temperature range of -55°C to +125°C and is available in a ceramic package.