Datasheet
DAC8x11
AV
DD
V
OUT
R
10kW
2
+5V
±5V
+5.5V
OPA211
10 Fm 0.1 Fm
Three-Wire
Serial
Interface
- 5.5V
R
10kW
1
REF5050
DAC8x11
+5V
110 Am
V
OUT
=0Vto5V
SYNC
SCLK
D
IN
+5.5V
Three-Wire
Serial
Interface
1 Fm
V
O
+
ǒ
10 D
2
n
Ǔ
*5V
V
O
+
ƪ
AV
DD
ǒ
D
2
n
Ǔ
ǒ
R
1
) R
2
R
1
Ǔ
* AV
DD
ǒ
R
2
R
1
Ǔ
ƫ
DAC8311
DAC8411
www.ti.com
SBAS439B –AUGUST 2008–REVISED MAY 2013
APPLICATION INFORMATION
USING THE REF5050 AS A POWER SUPPLY BIPOLAR OPERATION USING THE DAC8x11
FOR THE DAC8x11
The DAC8x11 has been designed for single-supply
As a result of the extremely low supply current operation but a bipolar output range is also possible
required by the DAC8x11, an alternative option is to using the circuit in Figure 78. The circuit shown gives
use a REF5050 +5V precision voltage reference to an output voltage range of ±5V. Rail-to-rail operation
supply the required voltage to the part, as shown in at the amplifier output is achievable using an
Figure 77. This option is especially useful if the power OPA211, OPA340, or OPA703 as the output
supply is too noisy or if the system supply voltages amplifier. For a full list of available operational
are at some value other than 5V. The REF5050 amplifiers from TI, see TI web site at www.ti.com
outputs a steady supply voltage for the DAC8x11. If
The output voltage for any input code can be
the REF5050 is used, the current needed to supply
calculated as follows:
DAC8x11 is typically 110μA at 5V, with no load on
the output of the DAC. When the DAC output is
loaded, the REF5050 also needs to supply the
current to the load. The total current required (with a
5kΩ load on the DAC output) is:
(1)
110μA + (5V/5kΩ) = 1.11mA
Where:
The load regulation of the REF5050 is typically
n = resolution in bits; either 14 (DAC8311) or 16
0.002%/mA, resulting in an error of 90μV for the
(DAC8411).
1.11mA current drawn from it. This value corresponds
D = the input code in decimal; either 0 to 16,383
to a 1.1LSB error at 16bit (DAC8411).
(DAC8311) or 0 to 65,535 (DAC8411).
With AV
DD
= 5V, R
1
= R
2
= 10kΩ:
(2)
This is an output voltage range of ±5V with 0000h
(16-bit level) corresponding to a –5V output and
FFFFh (16-bit level) corresponding to a +5V output.
Figure 77. REF5050 as Power Supply to DAC8x11
For other power-supply voltages, alternative
references such as the REF3030 (3V), REF3033
(3.3V), or REF3220 (2.048V) are recommended. For
a full list of available voltage references from TI, see
TI web site at www.ti.com.
Figure 78. Bipolar Operation with the DAC8x11
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