a
LC2MOS
Octal 12-Bit DAC
AD7568
FUNCTIONAL BLOCK DIAGRAM
FEATURES
Eight 12-Bit DACs in One Package
4-Quadrant Multiplication
Separate References
Single +5 V Supply
Low Power: 1 mW
Versatile Serial Interface
Simultaneous Update Capability
Reset Function
44-Pin PQFP and PLCC
VDD
AGND
VREF D VREF C VREF B VREF A
DGND
R FB A
AD7568
INPUT
LATCH A
12
DAC A
LATCH
12
DAC B
LATCH
12
I OUT1A
DAC A
I OUT2A
RFB B
INPUT
LATCH B
12
I OUT1B
DAC B
IOUT2 B
RFB C
INPUT
LATCH C
APPLICATIONS
Process Control
Automatic Test Equipment
General Purpose Instrumentation
12
DAC C
LATCH
12
DAC D
LATCH
12
I OUT1C
DAC C
I OUT2C
R FBD
INPUT
LATCH D
12
I OUT1D
DAC D
IOUT2 D
RFB E
INPUT
LATCH E
12
DAC E
LATCH
12
DAC F
LATCH
12
I OUT1E
DAC E
I OUT2E
GENERAL DESCRIPTION
RFB F
The AD7568 contains eight 12-bit DACs in one monolithic device. The DACs are standard current output with separate VREF,
IOUT1, IOUT2 and RFB terminals.
INPUT
LATCH F
IOUT1 F
DAC F
IOUT2 F
RFB G
INPUT
LATCH G
The AD7568 is a serial input device. Data is loaded using
FSIN, CLKIN and SDIN. One address pin, A0, sets up a device address, and this feature may be used to simplify device
loading in a multi-DAC environment.
All DACs can be simultaneously updated using the asynchronous LDAC input and they can be cleared by asserting the
asynchronous CLR input.
12
DAC G
LATCH
12
12
I OUT1G
DAC G
I OUT2G
R FBH
INPUT
LATCH H
DAC H
LATCH
12
12
I OUT1H
DAC H
I OUT2H
CONTROL LOGIC
+
INPUT SHIFT
REGISTER
12
FSIN
CLKIN
SDIN
The AD7568 is housed in a space-saving 44-pin plastic quad
flatpack and 44-lead PLCC.
A0
SDOUT
LDAC
CLR VREF E VREF F VREF G VREF H
PIN CONFIGURATIONS
NC 1
PIN 1 IDENTIFIER
33 NC
32 VREF C
R FB F 3
31 R FB C
IOUT1 F 4
30 I OUT1 C
AD7568 PQFP
AD7568
TOP VIEW
IOUT2 F 5
VREF G 6
IOUT2 D
IOUT1 D
2
1
44 43 42 41 40
RFB D
AGND
VREF D
VDD
3
DGND
RFB E
4
NC
7
VREF F
8
39 NC
38 VREF C
RFB F
9
37
RFB C
29 IOUT2 C
IOUT1 F 10
28 VREF B
TOP VIEW
Not to Scale
(Not to Scale)
R FB G 7
5
VREF E
IOUT2 E
6
VREF F 2
IOUT1 E
Plastic Leaded Chip Carrier
34 IOUT2 D
35 IOUT1 D
36 R FB D
37 VREF D
38 AGND
39 DGND
40 VDD
41 VREF E
42 R FB E
44 I OUT2E
43 I OUT1E
Plastic Quad Flatpack
IOUT2 F 11
AD7568 PLCC
35 IOUT2 C
VREF G 12
TOP VIEW
(Not to Scale)
34 VREF B
27 R FB B
36 IOUT1 C
RFB H 17
29 RFB A
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.
32 IOUT1 B
IOUT1 A
IOUT2 A
A0
SDIN
CLKIN
FSIN
LDAC
CLR
SDOUT
18 19 20 21 22 23 24 25 26 27 28
IOUT2 H
NC = NO CONNECT
33 RFB B
IOUT1 H
REV. B
I OUT1 A 22
30 VREF A
I OUT2 A 21
31 IOUT2 B
VREF H 16
A0 20
IOUT2 G 15
CLKIN 19
23 R FB A
FSIN 17
SDIN 18
R FB H 11
LDAC 16
IOUT1 G 14
CLR 15
RFB G 13
24 VREF A
SDOUT 14
25 IOUT2 B
VREF H 10
I OUT1 H 12
26 I OUT1 B
I OUT2H 13
IOUT1 G 8
IOUT2 G 9
NC = NO CONNECT
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 617/329-4700
Fax: 617/326-8703
