0.1 µF

2.7 V to 5.5 V

Shutdown

10 k

INA180

GND

VS

Load

IN±

IN+

OUT

+

±

Bus Voltage

±0.2 V to +26 V

Load

Output

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16

INA180, INA2180

SBOS741A – APRIL 2017 – REVISED AUGUST 2017

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Copyright © 2017, Texas Instruments Incorporated

Device Functional Modes (continued)

8.4.2 Input Differential Overload

the output as close as possible to the positive supply, and does not provide accurate measurement of the

differential input voltage. If this input overload occurs during normal circuit operation, then reduce the value of the

shunt resistor or use a lower-gain version with the chosen sense resistor to avoid this mode of operation. If a

differential overload occurs in a fault event, then the output of the INAx180 return to the expected value

approximately 20 µs after the fault condition is removed.

8.4.3 Shutdown Mode

Although the INAx180 do not have a shutdown pin, the low power consumption of the device allows the output of

a logic gate or transistor switch to power the INAx180. This gate or switch turns on and off the INAx180 power-

supply quiescent current.

However, in current shunt monitoring applications, there is also a concern for how much current is drained from

the shunt circuit in shutdown conditions. Evaluating this current drain involves considering the simplified

schematic of the INAx180 in shutdown mode, as shown in Figure 38.

Figure 38. Basic Circuit to Shut Down the INxA180

There is typically slightly more than 500 k

Ω of impedance (from the combination of 500-kΩ feedback and

input gain set resistors) from each input of the INAx180 to the OUT pin and to the GND pin. The amount of

current flowing through these pins depends on the voltage at the connection.

Regarding the 500-k

Ω path to the output pin, the output stage of a disabled INAx180 does constitute a good path

to ground. Consequently, this current is directly proportional to a shunt common-mode voltage present across a

500-k

Ω resistor.

common-mode input currents are negligible, and the only current effects are the result of the 500-k

Ω resistors.