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GENERAL DESCRIPTION The AD7569/AD7669 is a complete, 8-bit, analog I/O system on a single monolithic chip. The AD7569 contains a high speed successive approximation ADC with 2 µs conversion time, a track/ hold with 200 kHz bandwidth, a DAC and an output buffer amplifier with 1 µs settling time. A temperature-compensated 1.25 V bandgap reference provides a precision reference voltage for the ADC and the DAC. The AD7669 is similar, but contains two DACs with output buffer amplifiers. A choice of analog input/output ranges is available. Using a supply voltage of +5 V, input and output ranges of zero to 1.25 V and zero to 2.5 volts may be programmed using the RANGE in put pin. Using a ±5 V supply, bipolar ranges of ±1.25 V or ±2.5 V may be programmed. Digital interfacing is via an 8-bit I/O port and standard micro processor control lines. Bus interface timing is extremely fast, allowing easy connection to all popular 8-bit microprocessors. A separate start convert line controls the track/hold and ADC to give precise control of the sampling period. The AD7569/AD7669 is fabricated in Linear-Compatible CMOS (LC2MOS), an advanced, mixed technology process combining precision bipolar circuits with low power CMOS logic. The AD7569 is packaged in a 24-pin, 0.3" wide “skinny” DIP, a 24-terminal SOIC and 28-terminal PLCC and LCCC packages. The AD7669 is available in a 28-pin, 0.6" plastic DIP, 28-terminal SOIC and 28-terminal PLCC package. FEATURES 2 ms ADC with Track/Hold 1 ms DAC with Output Amplifier AD7569, Single DAC Output AD7669, Dual DAC Output On-Chip Bandgap Reference Fast Bus Interface Single or Dual 5 V Supplies |