Fastest, most accurate and lowest-power high-temp SAR ADC, claims ADI

October 09, 2014 // By Graham Prophet
Specified to 175C operation, the AD7981 PulSAR A/D converter targets high precision in harsh, high-temperature environments including downhole drilling, heavy industry and avionics.

Analog Devices claims the industry's highest speed, high-temperature, 16-bit, A/D converter, which it says is more than twice as fast as currently available converters and provides error-free operation at temperatures of up to 175C.

With sample rates up to 600-ksamples/sec, the AD7981 PulSAR A/D converter is suited for applications including wide bandwidth sonic and vibration measurement as well as low power, lower-bandwidth pressure and temperature sensing. The AD7981 maximises battery life in harsh environments by scaling power linearly with the sample rate, using only 4.65 mW at a full speed of 600 ksamples/sec and 70 µW at 10 ksamples/sec. The A/D converter features typical performance of ±0.7-LSB INL and 91-dB SNR enabling a high dynamic range with better accuracy and precision. This combination addresses critical performance criteria for precision measurement applications in harsh, high-temperature environments such as down-hole oil and gas drilling, as well as industrial and avionics applications.

The chip joins a series of precision high-temperature components, including the AD8229 ultra-low-noise instrumentation amplifier; the ADR225 2.5-V band gap voltage reference; the AD8634 dual amplifier with rail-to-rail outputs and the ADXRS645 MEMS (micro-electromechanical) gyroscope, all of which are specified to operate at 175C and higher.

Analog Devices;