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FEATURES
12-Bit Multiplying DACs
Guaranteed Specifications with +3.3 V/+5 V Supply
0.5 LSBs INL and DNL
Low Power: 5 W typ
Fast Interface
40 ns Strobe Pulsewidth (AD7943)
40 ns Write Pulsewidth (AD7945, AD7948)
Low Glitch: 60 nV-s with Amplifier Connected
Fast Settling: 600 ns to 0.01% with AD843
APPLICATIONS
Battery-Powered Instrumentation
Laptop Computers
Upgrades for All 754x Series DACs (5 V Designs)
V
REF
CLR
LD1
LD2
SRI
+3.3 V/+5 V Multiplying
12-Bit DACs
AD7943/AD7945/AD7948
FUNCTIONAL BLOCK DIAGRAMS
V
DD
R
FB
I
OUT1
I
OUT2
AGND
AD7943
12-BIT DAC
DAC REGISTER
INPUT SHIFT REGISTER
SRO
STB1 STB2
STB3
STB4
V
DD
R
FB
DGND
GENERAL DESCRIPTION
The AD7943, AD7945 and AD7948 are fast 12-bit multiplying
DACs that operate from a single +5 V supply (Normal Mode)
and a single +3.3 V to +5 V supply (Biased Mode). The
AD7943 has a serial interface, the AD7945 has a 12-bit parallel
interface, and the AD7948 has an 8-bit byte interface. They will
replace the industry-standard AD7543, AD7545 and AD7548
in many applications, and they offer superior speed and power
consumption performance.
The AD7943 is available in 16-lead DIP, 16-lead SOP (Small
Outline Package) and 20-lead SSOP (Shrink Small Outline
Package).
The AD7945 is available in 20-lead DIP, 20-lead SOP and 20-
lead SSOP.
The AD7948 is available in 20-lead DIP, 20-lead SOP and 20-
lead SSOP.
AD7945
V
REF
12-BIT DAC
12
CS
WR
INPUT LATCH
12
DB11–DB0
V
DD
R
FB
DGND
I
OUT1
AGND
V
REF
12-BIT DAC
12
DATA OVERRIDE LOGIC
12
DAC REGISTER
12
INPUT REGISTERS
12
DATA STEERING LOGIC
8
DB7–DB0
DGND
CONTROL
LOGIC
I
OUT1
AGND
AD7948
DF/DOR
CTRL
LDAC
WR
CSLSB
CSMSB
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