a
FEATURES
Specified for VDD of 3 V to 5.5 V
Read-Only Operation
AD7853–200 kSPS; AD7853L–100 kSPS
System and Self-Calibration with Autocalibration on
Power-Up
Low Power:
AD7853: 12 mW (VDD = 3 V)
AD7853L: 4.5 mW (VDD = 3 V)
Automatic Power Down After Conversion (25 W)
Flexible Serial Interface:
8051/SPI™/QSPI™/P Compatible
24-Lead DIP, SOIC and SSOP Packages
APPLICATIONS
Battery-Powered Systems (Personal Digital Assistants,
Medical Instruments, Mobile Communications)
Pen Computers
Instrumentation and Control Systems
High Speed Modems
3 V to 5 V Single Supply, 200 kSPS
12-Bit Sampling ADCs
AD7853/AD7853L*
FUNCTIONAL BLOCK DIAGRAM
AVDD
AGND
AIN(+)
AGND
AD7853/AD7853L
T/H
AIN(–)
DVDD
DGND
2.5V
REFERENCE
COMP
REFIN/
REFOUT
BUF
CREF1
AMODE
CHARGE
REDISTRIBUTION
DAC
CLKIN
CREF2
CAL
SAR + ADC
CONTROL
CONVST
BUSY
CALIBRATION
MEMORY
AND CONTROLLER
SLEEP
SERIAL INTERFACE / CONTROL REGISTER
GENERAL DESCRIPTION
The AD7853/AD7853L are high speed, low power, 12-bit
ADCs that operate from a single 3 V or 5 V power supply, the
AD7853 being optimized for speed and the AD7853L for low
power. The ADC powers up with a set of default conditions at
which time it can be operated as a read-only ADC. The ADC
contains self-calibration and system-calibration options to ensure accurate operation over time and temperature and have a
number of power-down options for low power applications.
The part powers up with a set of default conditions and can
operate as a read only ADC.
The AD7853 is capable of 200 kHz throughput rate while the
AD7853L is capable of 100 kHz throughput rate. The input
track-and-hold acquires a signal in 500 ns and features a pseudodifferential sampling scheme. The AD7853/AD7853L voltage
range is 0 to VREF with both straight binary and twos complement output coding. Input signal range is to the supply, and the
part is capable of converting full power signals to 100 kHz.
SM1 SM2 SYNC
DIN
DOUT SCLK POLARITY
PRODUCT HIGHLIGHTS
1. Specified for 3 V and 5 V supplies.
2. Automatic calibration on power-up.
3. Flexible power management options including automatic
power-down after conversion.
4. Operates with reference voltages from 1.2 V to VDD.
5. Analog input ranges from 0 V to VDD.
6. Self- and system calibration.
7. Versatile serial I/O port (SPI/QSPI/8051/µP).
8. Lower power version AD7853L.
CMOS construction ensures low power dissipation of typically
4.5 mW for normal operation and 1.15 mW in power-down
mode, with a throughput rate of 10 kSPS (VDD = 3 V). The part
is available in 24-lead, 0.3 inch wide dual-in-line package
(DIP), 24-lead small outline (SOIC) and 24-lead small shrink
outline (SSOP) packages.
*Patent pending.
SPI and QSPI are trademarks of Motorola, Incorporated.
REV. B
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
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
World Wide Web Site: http://www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 1998
