DAC7760 Datasheet, PDF (27/63 Pages) Texas Instruments – Single-Channel, 12- and 16-Bit Programmable Current Output and Voltage Output Digital-to-Analog Converters for 4-mA to 20-mA Current Loop Applications

www.ti.com
Feature Description (continued)
DAC7760, DAC8760
SBAS528B – JUNE 2013 – REVISED JUNE 2016
To Current Output
To Voltage Output
Figure 82. DAC Structure: Resistor String
The current-output stage converts the voltage output from the string to current. The voltage output provides a
buffered output of the programmed range to the external load. When the current output or the voltage output is
disabled, it is in a high impedance (Hi-Z) state. After power-on, both output stages are disabled. See Controlling
the VOUT and IOUT Pins for different options to configure the current and voltage output pins.
8.3.2 Voltage Output Stage
The voltage output stage as conceptualized in Figure 83 provides the voltage output according to the DAC code
and the output range setting. The output range can be programmed as 0 V to 5 V or 0 V to 10 V for unipolar
output mode, and ±5 V or ±10 V for bipolar output mode. In addition, an option is available to increase the output
voltage range by 10%. The output current drive can be up to 10 mA. The output stage has short-circuit current
protection that limits the output current to 30 mA. To maintain proper performance, a minimum 0.5-V power-
supply headroom is required. The voltage output is able to drive a capacitive load up to 1 µF. For loads greater
than 20 nF, an external compensation capacitor can be connected between CMP and VOUT to keep the output
voltage stable at the expense of reduced bandwidth and increased settling time.
12-/16-Bit
DAC
DACx760
+
í
RFB
VOUT
+VSENSE
Range
Scaling
íVSENSE
Figure 83. Voltage Output
The +VSENSE pin is provided to enable sensing of the load by connecting to points electrically closer to the
load. This configuration allows the internal output amplifier to make sure that the correct voltage is applied across
the load, as long as headroom is available on the power supply. Ideally, this pin is used to correct for resistive
drops on the system board and is connected to VOUT at the terminals. In some cases, both VOUT and
+VSENSE are brought out as terminals and, through separate lines, connected remotely together at the load. In
such cases, if the +VSENSE line is cut, the amplifier loop is broken; use an optional 5-kΩ resistor between
Copyright © 2013–2016, Texas Instruments Incorporated
Product Folder Links: DAC7760 DAC8760
Submit Documentation Feedback
27