120 mA, Current Sinking,
10-Bit, I
2
C
®
DAC
AD5821
Rev. 0
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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
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Fax: 781.461.3113 ©2007 Analog Devices, Inc. All rights reserved.
FEATURES
120 mA current sink
Available in 3 × 3 array WLCSP package
2-wire (I
2
C-compatible) 1.8 V serial interface
10-bit resolution
Integrated current sense resistor
2.7 V to 5.5 V power supply
Guaranteed monotonic over all codes
Power-down to 0.5 μA typical
Internal reference
Ultralow noise preamplifier
Power-down function
Power-on reset
CONSUMER APPLICATIONS
Lens autofocus
Image stabilization
Optical zoom
Shutters
Iris/exposure
Neutral density (ND) filters
Lens covers
Camera phones
Digital still cameras
Camera modules
Digital video cameras/camcorders
Camera-enabled devices
Security cameras
Web/PC cameras
INDUSTRIAL APPLICATIONS
Heater controls
Fan controls
Cooler (Peltier) controls
Solenoid controls
Valve controls
Linear actuator controls
Light controls
Current loop controls
GENERAL DESCRIPTION
The AD5821 is a single 10-bit digital-to-analog converter with
120 mA output current sink capability. It features an internal
reference and operates from a single 2.7 V to 5.5 V supply.
The DAC is controlled via a 2-wire (I
2
C-compatible) serial
interface that operates at clock rates up to 400 kHz.
The AD5821 incorporates a power-on reset circuit that ensures
that the DAC output powers up to 0 V and remains there until
a valid write takes place. It has a power-down feature that reduces
the current consumption of the device to 1 µA maximum.
The AD5821 is designed for autofocus, image stabilization, and
optical zoom applications in camera phones, digital still cameras,
and camcorders.
The AD5821 also has many industrial applications, such as
controlling temperature, light, and movement, over the range of
−40°C to +85°C without derating.
The I
2
C address for the AD5821 is 0x18.
FUNCTIONAL BLOCK DIAGRAM
R
SENSE
3.3Ω
R
AD5821
D1
10-BIT
CURRENT
OUTPUT DAC
05950-001
SDA
AGND
XSHUTDOWN
DD
DGND
SCL
I
SINK
DGND
V
DD
I
2
C SERIAL
INTERFACE
REFERENCE
POWER-ON
RESET
Figure 1.
