Differential Inputs, 500 kSPS, Dual Simultaneous Sampling SAR ADCs

The AD4680/AD4681 are 16-bit, pin-compatible, dual simultaneous sampling, high speed, low power, successive approximation register (SAR) analog-to-digital converters (ADCs) that operate from a 3.0 V to 3.6 V power supply and feature throughput rates of 1 MSPS for the AD4680 and 500 kSPS for the AD4681. The analog input type is differential, accepts a wide common-mode input voltage, and is sampled and converted on the falling edge of CS. Integrated on-chip oversampling blocks improve dynamic range and reduce noise at lower bandwidths. A buffered internal 2.5 V reference is included. Alternatively, an external reference up to 3.3 V can be used.

The conversion process and data acquisition use standard control inputs, allowing easy interfacing to microprocessors or digital signal processors (DSPs). The device is compatible with 1.8 V, 2.5 V, and 3.3 V interfaces using a separate logic supply. The AD4680/AD4681 are available in a 16-lead lead frame chip scale package (LFCSP) with operation specified from −40°C to +125°C.

APPLICATIONS

* Motor control position feedback

* Motor control current sense

* Sonar

* Power quality

* Data acquisition systems

* Erbium doped fiber amplifier (EDFA) applications

* Inphase (I) and quadrature (Q) demodulation

* 16-bit ADC family

* Dual simultaneous sampling

* Fully differential analog inputs

* Throughput conversion rate

* 1 MSPS for AD4680

* 500 kSPS for AD4681

* SNR (typical)

* 92.5 dB, VREF = 3.3 V external

* 100 dB with 8× OSR, RES = 1