THEORY OF OPERATION
The DAC7613 is a 12-bit, voltage output Digital-to-Analog
Converter (DAC). The architecture is a classic R-2R ladder
configuration followed by an operational amplifier that serves
as a buffer. The minimum voltage output (“zero-scale”) and
maximum voltage output (“full-scale”) are set by the exter-
nal voltage references (V
REFL
and V
REFH
, respectively). The
digital input is a 12-bit parallel word and the DAC input
register offers a readback capability. The converter can be
powered from a single +5V supply or a dual
±5V
supply.
The device offers a reset function which immediately sets
the DAC output voltage and DAC register to mid-scale
(code 800
H
) or to zero-scale (code 000
H
), depending on the
status of the reset selection. See Figures 1 and 2 for the basic
operation of the DAC7613.
DAC7613E
1
2
3
4
5
Data Bus
6
7
8
9
10
11
12
DB11
DB10
DB9
DB8
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
R/W
CS
RESETSEL
RESET
LOADDAC
V
OUT
V
DD
GND
V
SS
V
REFH
NIC
V
REFL
24
23
22
21
20
19
18
17
16
15
14
13
0.1µF
+2.5V
0.1µF
1µF
Read/Write
Chip Select
Reset Select
Reset DAC
Load DAC Register
0V to +2.5V
+
+5V
FIGURE 1. Basic Single-Supply Operation of the DAC7613.
DAC7613E
1
2
3
4
5
Data Bus
6
7
8
9
10
11
12
DB11
DB10
DB9
DB8
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
R/W
CS
RESETSEL
RESET
LOADDAC
V
OUT
V
DD
GND
V
SS
V
REFH
NIC
V
REFL
24
23
22
21
20
19
18
17
16
0.1µF
15
14
0.1µF
13
–2.5V
0.1µF
+2.5V
1µF
0.1µF
1µF
Read/Write
Chip Select
Reset Select
Reset DAC
Load DAC Register
–2.5V to +2.5V
+
+5V
+
–5V
FIGURE 2. Basic Dual-Supply Operation of the DAC7613.
®
7
DAC7613
TI [ TEXAS INSTRUMENTS ]
