The AD7656/AD7657/AD7658 contain six 16-/14-/12-bit, fast, low power, successive approximation ADCs all in the one package that is designed on the _i_CMOS™ process (industrial CMOS). _i_CMOS is a process combining high voltage silicon with submicron CMOS and complementary bipolar technologies. It enables the development of a wide range of high performance analog ICs, capable of 33 V operation in a footprint that no previous generation of high voltage parts could achieve. Unlike analog ICs using conventional CMOS processes, _i_CMOS components can accept bipolar input signals while providing increased performance, which dramatically reduces power consumption and package size.
The AD7656/AD7657/AD7658 feature throughput rates up to 250 kSPS. The parts contain low noise, wide bandwidth, track-and-hold amplifiers that can handle input frequencies up to 12 MHz.
The conversion process and data acquisition are controlled using CONVST signals and an internal oscillator. Three CONVST pins allow independent, simultaneous sampling of the three ADC pairs. The AD7656/AD7657/AD7658 all have a high speed parallel and serial interface, allowing the devices to interface with microprocessors or DSPs. In serial interface mode, the parts have a daisy-chain feature that allows multiple ADCs to connect to a single serial interface. The AD7656/ AD7657/AD7658 can accommodate true bipolar input signals in the ±4 × VREF range and ±2 × VREF range. The AD7656/ AD7657/AD7658 also contain an on-chip 2.5 V reference.
For reduced decoupling requirements visit the AD7657-1 product page
Product Highlights
1. Six 16-/14-/12-bit, 250 kSPS ADCs on board.
2. Six true bipolar, high impedance analog inputs.
3. Parallel and high speed serial interfaces.
**Applications**
Power line monitoring systems
Instrumentation and control systems
Multi-axis positioning systems
### Features and Benefits
6 independent ADCs
True bipolar analog inputs
Pin-/software-selectable ranges: ±10 V, ±5 V
Fast throughput rate: 250 kSPS
iCMOS process technology
Low power
140 mW at 250 kSPS with 5 V supplies
Wide input bandwidth 86.5 dB SNR at 50 kHz input frequency
On-chip reference and reference buffers
Parallel, serial, and daisy-chain interface modes
High speed serial interface SPI®-/QSPI™-/MICROWIRE™-/DSP-compatible
