Datasheet

DAC7800, 7801, 7802
6
SBAS005A
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BLOCK DIAGRAM
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
AGND
I
R
V
CS A
(LSB) DB0
DB1
DB2
DB3
DB4
DB5
DGND
I
R
V
V
CS B
WR
DB11 (MSB)
DB10
DB9
DB8
DB7
DB6
OUT A
FB A
REF A
FB B
REF B
DD
OUT B
DAC7802
TIMING CHARACTERISTICS
At V
DD
= +5V, and T
A
= –40
o
C to +85
o
C.
PARAMETER MINIMUM
t
1
- Data Setup Time 20ns
t
2
- Data Hold Time 15ns
t
3
- Chip Select to Write Setup Time 30ns
t
4
- Chip Select to Write Hold Time 0ns
t
5
- Write Pulse Width 30ns
LOGIC TRUTH TABLE
CSA CSB WR FUNCTION
X X 1 No Data Transfer
1 1 X No Data Transfer
0 A Rising Edge on CSA or CSB Loads
Data to the Respective DAC
01 DAC A Register Loaded from Data Bus
10
DAC B Register Loaded from Data Bus
00
DAC A and DAC B Registers Loaded
from Data Bus
X = Don’t care.
means rising edge triggered.
PIN CONFIGURATION
DAC7802
DATA
5V
0V
5V
5V
CSA, CSB
WR
t
2
t
1
t
3
t
4
t
5
NOTES: (1) All input signal rise and fall times are measured from 10%
to 90% of +5V. t
R
= t
R
= 5ns. (2) Timing measurement reference level
is
V
IH
+ V
IL
2
.
CK
DAC B
DAC A
12
12
12
12
12
DGND
18
CS A
5
CS B 20
WR 19
21
V
DD
DAC7802
6
2 I
3 R
OUT A
FB A
23 R
24 I
1 AGND
FB B
OUT B
DAC A Register
CK
DAC B Register
DB11–DB0
4
22
V
V
REF A
REF B
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