AD7656A 250 kSPS, 6-Channel, Simultaneous Sampling, Bipolar 16-Bit ADC

Six 16-bit, 250 kSPS ADCs on board. Six true bipolar, high impedance analog inputs. Parallel and high speed serial interfaces. APPLICATIONS Power line monitoring systems Instrumentation and control systems Multi-axis positioning systems

The AD7656A contains six 16-bit, fast, low power, successive approximation analog-to-digital converters (ADCs) all in the one package that is designed on the iCMOS® process (industrial CMOS). iCMOS 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 devices could achieve. Unlike analog ICs using conventional CMOS processes, iCMOS components can accept bipolar input signals while providing increased performance, which dramatically reduces power consumption and package size.

The AD7656A features throughput rates of up to 250 kSPS. It contains wide bandwidth (12 MHz), track-and-hold amplifiers that can handle input frequencies up to 12 MHz.

The conversion process and data acquisition are controlled using CONVST x signals and an internal oscillator. Three CONVST x pins (CONVST A, CONVST B, and CONVST C) allow independent, simultaneous sampling of the three ADC pairs. The AD7656A has a high speed parallel and serial interface, allowing the device to interface with microprocessors or digital signal processors (DSPs). In serial interface mode, the AD7656A has a daisy-chain feature that allows multiple ADCs to connect to a single serial interface. The AD7656A can accommodate true bipolar input signals in the ±4 × VREF range and ±2 × VREF range. The AD7656A also contains an on-chip 2.5 V reference.

Multifunction pin names may be referenced by their relevant function only.

Please visit next generation product AD7606. For reduced decoupling requirements visit the AD7656A-1 product page.

PRODUCT HIGHLIGHTS

APPLICATIONS

Power line monitoring systems
Instrumentation and control systems
Multi-axis positioning systems

Features and Benefits

6 independent analog-to-digital converters (ADCs)
True bipolar analog inputs
Pin-/software-selectable ranges: ±10 V or ±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

On-chip reference and reference buffers
Parallel, serial, and daisy-chain interface modes
High speed serial interface
Serial peripheral interface (SPI)/QSPI™/MICROWIRE®/DSP compatible
Power-down mode:
100 mW maximum
64-lead LQFP
Improved power supply sequencing (PSS) robustness

Analog to Digital Converters

Data Sheets

Document	note
AD7656A: 250 kSPS, 6-Channel, Simultaneous Sampling, Bipolar 16-Bit ADC Data Sheet (Rev. 0)	PDF 491 kB

Application Notes

Document	note
AN-931: Understanding PulSAR ADC Support Circuitry (Rev. 0)	PDF 299 kB
AN-893: Configuring the AD7656/AD7657/AD7658 for Serial and Daisy-Chain Interface Modes of Operation (Rev. 0)	PDF 133 kB