10-bit successive approximation ADC

The AD573 is a complete 10-bit successive approximation analog-to-digital converter consisting of a DAC, voltage reference, clock, comparator, successive approximation register (SAR) and three state output buffers- all fabricated on a single chip. No external components are required to perform a full accuracy 10-bit conversion in 20 µs.

The AD573 incorporates advanced integrated circuit design and processing technologies. The successive approximation function is implemented with I2L (integrated injection logic). Laser trimming of the high stability SiCr thin-film resistor ladder network insures high accuracy, which is maintained with a temperature compensated subsurface Zener reference.

Operating on supplies of +5 V and -12 V to -15 V, the AD573 will accept analog inputs of 0 V to +10 V or -5 V to +5 V. The trailing edge of a positive pulse on the CONVERT line initiates the 20µs conversion cycle. DATA READY indicates completion of the conversion. HIGH BYTE ENABLE (HBE) and LOW BYTE ENABLE (LBE) control the 8-bit and 2-bit three state output buffers.

The AD573 is available in two versions for the 0°C to +70°C temperature range, the AD573J and AD573K. The AD573S guarantees ±1 LSB relative accuracy and no missing codes from -55°C to +125°C.

Three package configurations are offered. All versions are offered in a 20-pin hermetically sealed ceramic DIP. The AD573J and AD573K are also available in a 20-pin plastic DIP or 20-pin leaded chip carrier.

PRODUCT HIGHLIGHTS

* The AD573 is a complete 10-bit A/D converter. No external

components are required to perform a conversion.

* The AD573 interfaces to many popular microprocessors

without external buffers or peripheral interface adapters. The

10 bits of output data can be read as a 10-bit word or as 8-

and 2-bit words.

* The device offers true 10-bit accuracy and exhibits no missing

codes over its entire operating temperature range.

* The AD573 adapts to either unipolar (0 V to +10 V) or

bipolar (–5 V to +5 V) analog inputs by simply grounding or

opening a single pin.

* Performance is guaranteed with +5 V and –12 V or –15 V

supplies.

* The AD573 is available in a version compliant with MIL-STD-

883. Refer to the Analog Devices Military Products Databook

or current /883B data sheet for detailed specifications.

* Complete 10-Bit A/D Converter with Reference, Clock and Comparator

* Full 8- or 16-Bit Microprocessor Bus Interface

* Fast Successive Approximation Conversion—20 µs typ