ISC300 Datasheet, PDF (6/11 Pages) Burr-Brown (TI) – Universal Precision Isolated MEASUREMENT CHANNEL

Figure 4 shows the configuration for voltage measurement.
A full scale input range of ±10V can be accepted by the
ISC300. The two sense lines can be connected to give open
or short circuit detection. An open circuit will result in an
output of < –5.1V and a short circuit will give a < 0.1V
output. See the Applications section under Fault Conditions
for more information.
Figure 7 shows a possible circuit configuration using jump-
ers to select voltage or RTD operation.
ISOLATED SUPPLIES
The two isolated supplies available on the input side are
capable of supplying ±11.5V min at 5mA. These can be used
to provide power for external front-end circuitry for addi-
tional signal processing. When using the isolated supplies, it
is necessary to decouple them as close to the device as
possible. 10µF tantalum capacitors should be used. This will
also improve the signal-to-noise ratio.
0Ω
to
R_S
500Ω
Line Resistance
I_REF1
I_REF2
Com 1
Com 1
+In
Filter and
– In
MUX
Sense 2 ^20MΩ
I₁
I₂
–V_ISO
FIGURE 3. Resistance Measurement Configuration.
PGA
+V_ISO
–10V
to
+10V
Line Resistance
Sense 1 ^20MΩ
+In
Filter and
–In
MUX
Sense 2 ^20MΩ
Com 1
–V_ISO
PGA
+V_ISO
FIGURE 4. Voltage Measurement Configuration.
®
ISC300
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