REV. B
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a
AD7810
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., 2000
2.7 V to 5.5 V, 2.3 s, 10-Bit
ADC in 8-Lead microSOIC/DIP
FUNCTIONAL BLOCK DIAGRAM
CLOCK
OSC
D
OUT
SCLK
V
REF
AGND
V
DD
V
IN
+
V
IN
–
CONVST
SERIAL
PORT
CHARGE
REDISTRIBUTION
DAC
CONTROL
LOGIC
AD7810
COMP
V
DD
/
3
FEATURES
10-Bit ADC with 2.3 s Conversion Time
Small Footprint 8-Lead microSOIC Package
Specified Over a –40ⴗC to +105ⴗC Temperature Range
Inherent Track-and-Hold Functionality
Operating Supply Range: 2.7 V to 5.5 V
Specifications at 2.7 V to 5.5 V
Microcontroller-Compatible Serial Interface
Optional Automatic Power-Down
at End of Conversion
Low Power Operation
270 W at 10 kSPS Throughput Rate
2.7 mW at 100 kSPS Throughput Rate
Analog Input Range: 0 V to V
REF
Reference Input Range: 0 V to V
DD
APPLICATIONS
Low Power, Hand-Held Portable Applications that
Require Analog-to-Digital Conversion with 10-Bit
Accuracy; e.g., Battery Powered Test Equipment,
Battery-Powered Communications Systems
GENERAL DESCRIPTION
The AD7810 is a high speed, low power, 10-bit A/D con-
verter that operates from a single 2.7 V to 5.5 V supply. The
part contains a 2.3 µs successive approximation A/D converter,
with inherent track/hold functionality, a pseudo differential
input and a high speed serial interface that interfaces to most
microcontrollers. The AD7810 is fully specified over a tem-
perature range of –40°C to +105°C.
By using a technique that samples the state of the CONVST
(convert start) signal at the end of a conversion, the AD7810
may be used in an automatic power-down mode. When used in
this mode, the AD7810 automatically powers down at the end
of a conversion and “wakes up” at the start of a new conversion.
This feature significantly reduces the power consumption of the
part at lower throughput rates. The AD7810 can also operate in
a high speed mode where the part is not powered down between
conversions. In this high speed mode of operation, the conver-
sion time of the AD7810 is 2.3 µs. The maximum throughput
rate is dependent on the speed of the serial interface of the
microcontroller.
The part is available in a small 8-lead, 0.3" wide, plastic dual-
in-line package (mini-DIP); in an 8-lead, small outline IC
(SOIC); and in an 8-lead microSOIC package.
PRODUCT HIGHLIGHTS
1. Complete, 10-Bit ADC in 8-Lead Package
The AD7810 is a 10-bit 2.3 µs ADC with inherent track/hold
functionality and a high speed serial interface—all in an
8-lead microSOIC package. V
REF
may be connected to V
DD
to eliminate the need for an external reference. The result is
a high speed, low power, space saving ADC solution.
2. Low Power, Single Supply Operation
The AD7810 operates from a single 2.7 V to 5.5 V supply
and typically consumes only 9 mW of power while convert-
ing. The power dissipation can be significantly reduced at
lower throughput rates by using the automatic power-down
mode, e.g., at a throughput rate of 10 kSPS the power
consumption is only 270 µW.
3. Automatic Power-Down
The automatic power-down mode, whereby the AD7810
powers down at the end of a conversion and “wakes up”
before the next conversion, means the AD7810 is ideal for
battery powered applications. See Power vs. Throughput
Rate section.
4. Serial Interface
An easy to use, fast serial interface allows connection to most
popular microprocessors with no external circuitry.
