2.7 V to 5.5 V, 2.3 s, 10-Bit
ADC in 8-Lead microSOIC/DIP
a
AD7810
FUNCTIONAL BLOCK DIAGRAM
FEATURES
10-Bit ADC with 2.3 s Conversion Time
Small Footprint 8-Lead microSOIC Package
Specified Over a –40؇C to +105؇C 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
V
V
AGND
DD
REF
AD7810
CHARGE
REDISTRIBUTION
DAC
D
OUT
SERIAL
PORT
SCLK
CLOCK
OSC
V
V
+
–
IN
CONTROL
LOGIC
COMP
Low Power Operation
IN
3
/
V
DD
270 W at 10 kSPS Throughput Rate
2.7 mW at 100 kSPS Throughput Rate
Analog Input Range: 0 V to VREF
Reference Input Range: 0 V to VDD
CONVST
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
PRODUCT HIGHLIGHTS
1. Complete, 10-Bit ADC in 8-Lead Package
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.
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. VREF may be connected to VDD
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
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 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.
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.
4. Serial Interface
An easy to use, fast serial interface allows connection to most
popular microprocessors with no external circuitry.
REV. B
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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
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© Analog Devices, Inc., 2000