3-Msample/s 16-Bit SAR ADC Sports 1-LSB Accuracy

High-speed 16-bit successive-approximation-register (SAR) analog-to-digital converters (ADCs) are available, but many of them sacrifice integral and differential linearity (INL and DNL) to achieve high speeds. However, Analog Devices' AD7621 16-bit SAR ADC won't trade off accuracy for higher speed. It provides 50% higher speeds and three times the accuracy of competing products, all in packaging that's 40% smaller.

Speed- and accuracy-critical applications can take advantage of this zero-data-latency device, which is part of the company's PulSAR family of SAR converters. The AD7621 operates at 3 Msamples/s while providing ±1-LSB (least-significant bit) INL, ±1-LSB DNL, and no missing codes. It also consumes less than 100 mW at 3 Msamples/s.

"When designers are considering SAR converters, speed alone is not the only performance criteria," says Mike Britchfield, product line director for precision converters. "With the AD7621, there are no compromises. High performance means speed and accuracy, combined with low power consumption, standard packaging, and a competitive price."

Typical power dissipation is 100 mW at a single 5-V supply. Signal-to-noise ratio is 90 dB. The ADC features an internal conversion clock and reference buffer, error-correction circuits, and both serial and parallel interface ports.

Priced at $29.95 each in 1000-unit lots, the AD7621 comes in 48-lead 7- by 7-mm LQFPs and LFCSPs. Production quantities will be available in June.