XTR111_07 BURR-BROWN [Burr-Brown Corporation], XTR111_07 Datasheet - Page 16

• Manufacturer Part Number: XTR111_07
• Description: Precision Voltage-to-Current Converter/Transmitter
• Manufacturer: BURR-BROWN [Burr-Brown Corporation]

XTR111
SBOS375 − NOVEMBER 2006
The voltage at REGF is limited by the supply voltage. If the
supply voltage drops close to the set voltage, the driver
output saturates and follows the supply with a voltage drop
of less than 1V (depending on load current and
temperature).
For good stability and transient response, use a load
capacitance of 470nF or larger. The bias current into the
sense input (REGS) is typically less than 1µA. This current
should be considered when selecting high resistance
values for the voltage setting because it lowers the voltage
and produces additional temperature dependence.
16
Figure 10. Current or Voltage Output (SW1) Using 0V to 5V Input from a 12-Bit Digital-to-Analog
Digital I/O
5V
12− Bit Digital−to−Analog
Converter
DAC7551
C
470nF
2
2.5k Ω
R
2kΩ
R
3k Ω
R
1
2
3
APPLICATION BLOCK DIAGRAMS
5
4
6
REGF
REGS
3V
VIN
10
GND
Converter DAC7551
The REGF output cannot sink current. In case of supply
voltage loss, the output is protected against the discharge
currents from load capacitors by internal protection
diodes; the peak current should not exceed 25mA.
If the voltage regulator output is not used, connect REGF
to REGS (the 3V mode) loaded with a 2.2nF capacitor.
Alternatively, overdrive the loop pulling REGS high (see
Figure 9d).
1
VSP
7
SET
R
2.5k Ω
Current
S ET
Mirror
Switch for current
or voltage output
SW1
OD
VG
EF
IS
9
8
2
3
G
S
D
Q
C
1
L O A D
R
LO AD
0mA to 20mA or
0V to 5V Output
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