+5 Volt, Serial Input,
Dual 12-Bit DAC
a
AD8522
FEATURES
FUNCTIO NAL BLO CK D IAGRAM
Com plete Dual 12-Bit DAC
No External Com ponents
V
DD
+5 V Single-Supply Operation ؎10%
4.095 V Full Scale (1 m V/ LSB)
Buffered Voltage Outputs
Low Pow er: 5 m W/ DAC
CS
OP
AMP
A
CLK
LATCH
DAC A
V
OUTA
DAC A
REGISTER
CLK
12
D
SDI
(DATA)
BANDGAP
REFERENCE
REF
BUF
Space Saving 1.5 m m Height SO-14 Package
12
SHIFT
REGISTER
V
REF
APPLICATIONS
Digitally Controlled Calibration
Servo Controls
Process Control Equipm ent
Com puter Peripherals
Portable Instrum entation
Cellular Base Stations Voltage Adjustm ent
REF
BUF
D
DAC B
SDO
REGISTER
12
OP
V
DAC B
AD8522
AGND
AMP
OUTB
LDA
LDB
CONTROL
LOGIC
B
DGND
MSB
RS
GENERAL D ESCRIP TIO N
inputs. A serial data output allows the user to easily daisy-chain
multiple devices in conjunction with a chip select input. A reset
RS input sets the outputs to zero scale or midscale, as deter-
mined by the input MSB.
T he AD8522 is a complete dual 12-bit, single-supply, voltage
output DAC in a 14-pin DIP, or SO-14 surface mount package.
Fabricated in a CBCMOS process, features include a serial digi-
tal interface, onboard reference, and buffered voltage output.
Ideal for +5 V-only systems, this monolithic device offers low
cost and ease of use, and requires no external components to
realize the full performance of the device.
T he output 4.095 V full scale is laser trimmed to maintain accu-
racy over the operating temperature range of the device, and
gives the user an easy-to-use one-millivolt-per-bit resolution. A
2.5 V reference output is also available externally for other data
acquisition circuitry, and for ratiometric applications. T he out-
put buffers are capable of driving ±5 mA.
T he serial digital interface allows interfacing directly to numer-
ous microcontroller ports, with a simple high speed, three-wire
data, clock, and load strobe format. T he 16-bit serial word con-
tains the 12-bit data word and DAC select address, which is de-
coded internally or can be decoded externally using LDA, LDB
T he AD8522 is available in the 14-pin plastic DIP and low pro-
file 1.5 mm SOIC-14 packages.
0.6
P ACKAGE TYP ES AVAILABLE
V
T
= +4.5V
DD
= –55°C, +25°C, +85°C, +125°C
0.4
0.2
A
+25°C
–55°C
0
–0.2
–0.4
–0.6
–0.8
–1.0
PDIP-14
+85°C
SO-14
+125°C
0
1024
2048
3072
4096
DIGITAL INPUT CODE – Decimal
Figure 1. Linearity Error vs. Digital Code & Tem perature
REV. A
Inform ation furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assum ed by Analog Devices for its
use, nor for any infringem ents of patents or other rights of third parties
which m ay result from its use. No license is granted by im plication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norw ood. MA 02062-9106, U.S.A.
Tel: 617/ 329-4700
Fax: 617/ 326-8703