ANALOG DEVICES AD7655-EP Service Manual

Low Cost, 4-Channel, 16-Bit 1 MSPS

AD7655-EP

CONTROL LOGIC AND

CALIBRATION CI RCUITRY

A/B

16

D[15:0]

BUSY
CS

SER/PAR

OGND

OVDD

DGND

DVDD

SERIAL

PORT

BYTESWAP

RD

AVDD AGND REFxREFGND

PD

RESET

CNVST

INAN

SWITCHED

CAP DAC

AD7655-EP

INA1

IMPULSE

MUX

EOC

INA2

A0

INB1
INBN
INB2

TRACK/HOLD

×2

PARALLEL

INTERFACE

CLOCK

MUX

MUX

09230-001

FEATURES

4-channel, 16-bit resolution ADC
2 track-and-hold amplifiers
Throughput

1 MSPS (normal mode)

888 kSPS (impulse mode)
Analog input voltage range: 0 V to 5 V
No pipeline delay
Parallel and serial 5 V/3 V interface
SPI®/QSPI™/MICROWIRE™/DSP compatible
Single 5 V supply operation
Power dissipation

120 mW typical

2.6 mW @ 10 kSPS
48-lead frame chip scale package (LFCSP)
Pin-to-pin compatible with the AD7654
Low cost
Supports defense and aerospace applications (AQEC

standard)
Military temperature range (−55°C to +125°C)
Controlled manufacturing baseline
Enhanced product change notification
Qualification data available on request

APPLICATIONS

AC motor control

3-phase power control

4-channel data acquisition

Uninterrupted power supplies

Communications

GENERAL DESCRIPTION

The AD7655-EP is a low cost, simultaneous sampling, dual­channel, 16-bit, charge redistribution SAR, analog-to-digital
converter that operates from a single 5 V power supply. It
contains two low noise, wide bandwidth, track-and-hold
amplifiers that allow simultaneous sampling, a high speed
16-bit sampling ADC, an internal conversion clock, error
correction circuits, and both serial and parallel system interface
ports. Each track-and-hold has a multiplexer in front to provide
a 4-channel input ADC. The A0 multiplexer control input
allows the choice of simultaneously sampling input pairs
INA1/INB1 (A0 = low) or INA2/ INB2 (A0 = high). The part
features a very high sampling rate mode (normal) and, for low

Rev. A

Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.

PulSAR ADC

FUNCTIONAL BLOCK DIAGRAM

Figure 1.

Table 1. PulSAR® Selection

800 to

Type/kSPS 100 to 250 500 to 570

Pseudo
Differential

True Bipolar AD7663 AD7665 AD7671
True

Differential
18 Bit AD7678 AD7679 AD7674 AD7641
Multichannel/

Simultaneous

AD7660/
AD7661

AD7675 AD7676 AD7677

AD7654 AD7655

AD7650/
AD7652
AD7664/
AD7666

power applications, a reduced power mode (impulse) where the
power is scaled with the throughput. Operation is specified
from −55°C to +125°C.

Full details about this enhanced product are available in the

AD7655 data sheet, which should be consulted in conjunction

with this data sheet.

PRODUCT HIGHLIGHTS

1. Multichannel ADC.

The AD7655-EP features 4-channel inputs with two sample­and-hold circuits that allow simultaneous sampling.

2. Fast Throughput.

The AD7655-EP is a 1 MSPS, charge redistribution, 16-bit
SAR ADC with internal error correction circuitry.

3. Single-Supply Operation.

The AD7655-EP operates from a single 5 V supply. In impulse
mode, its power dissipation decreases with throughput.

4. Serial or Parallel Interface.

Versatile parallel or 2-wire serial interface arrangements
are compatible with both 3 V and 5 V logic.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone]
Fax: [phone] ©2010–2011 Analog Devices, Inc. All rights reserved.

1000

AD7653
AD7667

www.analog.com

>1000

AD7621
AD7623