16-Bit, 16-Channel, 1 MSPS, Easy Drive Multiplexed SAR ADC

The AD4695/AD4696 are compact, high accuracy, low power, 16-channel, 16-bit, 500 kSPS/1 MSPS, multiplexed input precision, successive approximation register (SAR) analog-to-digital converters (ADCs) with Easy Drive features and extensive digital functionality.

The AD4695/AD4696 are optimal for use in space constrained, multichannel, precision data acquisition systems and monitoring circuits. The AD4695/AD4696 feature a true 16-bit SAR ADC core with no missing codes, a 16-channel, low crosstalk multiplexer, a flexible channel sequencer, overvoltage protection clamp circuits on each analog input, on-chip oversampling and decimation, threshold detection and alert indicators, and an autonomous conversion (autocycle) mode.

The AD4695/AD4696 Easy Drive features relax the drive requirements of the analog front end (AFE) and reference circuitry. Analog input high-Z mode and reference input high‑Z mode simplify system designs, reduce component count, and increase channel density by removing the need for dedicated high speed ADC drivers and reference buffers. The WLCSP option of the AD4695/AD4696 includes an internal reference buffer, which provides a true, buffered reference input.

Input overvoltage protection clamps on each analog input protect the AD4695/AD4696 from overvoltage events and prevent overvoltage events on one channel from degrading performance on other channels (see Figure 27 in the data sheet).

Advanced digital functionality makes the AD4695/AD4696 compatible with a variety of low power digital hosts. The low serial peripheral interface (SPI) clock rate requirements, on-chip customizable channel sequencers, and oversampling and decimation reduce the burden on the digital host system. Autocycle mode and threshold detection features enable low power, interrupt driven firmware design by performing conversions autonomously and generating alerts based on channel specific threshold limits.

The AD4695/AD4696 are available in a 5 mm × 5 mm 32-lead lead frame chip scale package (LFCSP) and a 2.96 mm × 2.96 mm 36-ball wafer level chip scale package (WLCSP) with operation specified from −40°C to +125°C.

APPLICATIONS

* Photodiode monitoring

* Medical instrumentation

* Vital signs monitoring

* Electronic test and measurement

* Automated test equipment

* Instrumentation and process control

* Battery-powered equipment

* Easy Drive

* Reduced analog input and reference drive requirements

* On-chip reference buffer (WLCSP only)

* Overvoltage protection up to 5 mA on each analog input

* Long acquisition phase, ≥71.5% (715 ns/1000 ns) of cycle time at 1 MSPS

* High performance

* Sample rate: 500 kSPS (AD4695) or 1 MSPS (AD4696)

* INL: ±1.0 LSB maximum

* Guaranteed 16-bit, no missing codes

* SINAD: 93 dB typical, fIN = 1 kHz

* Oversampled dynamic range: 111.2 dB, OSR = 64

* Small footprint, high channel density

* 32-lead 5 mm × 5 mm LFCSP

* 36-ball 2.96 mm × 2.96 mm WLCSP

* Easy Drive features support system level designs with fewer components