DAC8550_16 Datasheet, PDF (19/31 Pages) Texas Instruments – 16-bit, Ultra-Low Glitch, Voltage Output Digital-To-Analog Converter

www.ti.com
8 Application and Implementation
DAC8550
SLAS476F – MARCH 2006 – REVISED MARCH 2016
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
The low-power consumption of the DAC8550 lends itself to applications such as loop-powered control where the
current dissipation of each device is critical. The low power consumption also allows the DAC8550 to be powered
using only a precision reference for increased accuracy. The low-power operation coupled with the ultra-low
power power-down modes also make the DAC8550 a great choice for battery and portable applications.
8.1.1 Bipolar Operation Using DAC8550
The DAC8550 has been designed for single-supply operation, but a bipolar output range is also possible using
the circuit in Figure 51. The circuit shown gives an output voltage range of ±V_REF. Rail-to-rail operation at the
amplifier output is achievable using an OPA703 as the output amplifier. See CMOS, Rail-to-Rail, I/O Operational
Amplifier (SBOS180) for more information.
V
REF
R₂
10kW
R₁
+6V
10kW
OPA703
5V
V_FB
V_{REF DAC8550} V_OUT
10mF
0.1mF
-6V
Three-Wire
Serial Interface
Figure 51. Bipolar Output Range
The output voltage for any input code is calculated with Equation 2 and Equation 3.
V_O
=
éæ
êëêçè
V_REF
2
+
V_REF
´
D
65536
ö
÷ø
´
æ
ç
è
R₁ + R
R₁
2
ö
÷
-
ø
V_REF
´
æ
ç
R
2
è ^R1
öù
÷ú
øúû
where
• D represents the input code in 2's complement (–32768 to 32767)
• V_REF = 5 V
• R₁ = R₂ = 10 kΩ
(2)
D
V_O = 10 ´ ₆₅₅₃₆
(3)
Using this example, an output voltage range of ±5 V with 8000h corresponding to a –5-V output and 8FFFh
corresponding to a 5-V output can be achieved. Similarly, using V_REF = 2.5 V, a ±2.5-V output voltage range can
be achieved.
Copyright © 2006–2016, Texas Instruments Incorporated
Product Folder Links: DAC8550
Submit Documentation Feedback
19