a
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
APPLICATIONS
Process Control
Automatic Test Equipment
General Purpose Instrumentation
GENERAL DESCRIPTION
V
DD
AGND
DGND
LC MOS
Octal 12-Bit DAC
AD7568
FUNCTIONAL BLOCK DIAGRAM
V
REF
D V
REF
C V
REF
B V
REF
A
R
FB
A
2
AD7568
INPUT
LATCH A
12
DAC A
LATCH
12
DAC A
I
OUT1
A
I
OUT2
A
R
FB
B
INPUT
LATCH B
12
DAC B
LATCH
12
DAC B
I
OUT1
B
I
OUT2
B
R
FB
C
INPUT
LATCH C
12
DAC C
LATCH
12
DAC C
I
OUT1
C
I
OUT2
C
R
FB
D
INPUT
LATCH D
12
DAC D
LATCH
12
DAC D
I
OUT1
D
I
OUT2
D
R
FB
E
INPUT
LATCH E
12
DAC E
LATCH
12
DAC E
I
OUT1
E
I
OUT2
E
R
FB
F
INPUT
LATCH F
12
DAC F
LATCH
12
DAC F
I
OUT1
F
I
OUT2
F
R
FB
G
INPUT
LATCH G
12
DAC G
LATCH
12
DAC G
I
OUT1
G
I
OUT2
G
R
FB
H
INPUT
LATCH H
12
DAC H
LATCH
12
DAC H
I
OUT1
H
I
OUT2
H
The AD7568 contains eight 12-bit DACs in one monolithic de-
vice. The DACs are standard current output with separate V
REF
,
I
OUT1
, I
OUT2
and R
FB
terminals.
The AD7568 is a serial input device. Data is loaded using
FSIN,
CLKIN and SDIN. One address pin, A0, sets up a de-
vice address, and this feature may be used to simplify device
loading in a multi-DAC environment.
All DACs can be simultaneously updated using the asynchro-
nous
LDAC
input and they can be cleared by asserting the
asynchronous
CLR
input.
The AD7568 is housed in a space-saving 44-pin plastic quad
flatpack and 44-lead PLCC.
PIN CONFIGURATIONS
Plastic Quad Flatpack
35 I
OUT1
D
34 I
OUT2
D
44 I
OUT2
E
43 I
OUT1
E
41 V
REF
E
37 V
REF
D
39 DGND
38 AGND
36 R
FB
D
42 R
FB
E
40 V
DD
FSIN
CLKIN
SDIN
CONTROL LOGIC
+
INPUT SHIFT
REGISTER
12
A0
SDOUT
LDAC
CLR V
REF
E V
REF
F V
REF
G V
REF
H
Plastic Leaded Chip Carrier
I
OUT1
E
V
REF
E
DGND
AGND
V
REF
D
R
FB
D
I
OUT1
D
I
OUT2
D
39 NC
38 V
REF
C
37
R
FB
C
36 I
OUT1
C
35 I
OUT2
C
34 V
REF
B
33 R
FB
B
32 I
OUT1
B
31 I
OUT2
B
30 V
REF
A
29 R
FB
A
18 19 20 21 22 23 24 25 26 27 28
I
OUT2
E
R
FB
E
6
NC 1
V
REF
F 2
R
FB
F 3
I
OUT1
F 4
I
OUT2
F 5
V
REF
G 6
R
FB
G 7
I
OUT1
G 8
I
OUT2
G 9
V
REF
H 10
R
FB
H 11
5
4
V
DD
2
3
1
44 43 42 41 40
PIN 1 IDENTIFIER
33 NC
32 V
REF
C
31 R
FB
C
NC
V
REF
F
R
FB
F
7
8
9
AD7568 PQFP
AD7568
TOP VIEW
TOP VIEW
Not to Scale
(Not to Scale)
30 I
OUT1
C
29 I
OUT2
C
28 V
REF
B
27 R
FB
B
26 I
OUT1
B
25 I
OUT2
B
24 V
REF
A
23 R
FB
A
I
OUT1
F 10
I
OUT2
F 11
V
REF
G 12
R
FB
G 13
I
OUT1
G 14
I
OUT2
G 15
V
REF
H 16
AD7568 PLCC
TOP VIEW
(Not to Scale)
I
OUT2
H 13
I
OUT1
H 12
SDOUT 14
CLR 15
FSIN 17
SDIN 18
I
OUT2
A 21
I
OUT1
A 22
CLKIN 19
LDAC 16
A0 20
R
FB
H 17
I
OUT2
A
I
OUT1
H
I
OUT2
H
REV. B
NC = NO CONNECT
SDOUT
NC = NO CONNECT
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: 617/329-4700
Fax: 617/326-8703
I
OUT1
A
SDIN
FSIN
CLKIN
CLR
LDAC
A0
AD [ ANALOG DEVICES ]
