DIO2186

Version 1.0, Apr 2026

www.dioo.com

© 2026 Dioo Microcircuits Co., Ltd. Jiangsu

13

representation at the output, both positive and negative output swing boundaries must be considered. The

maximum allowable values of RShunt and Gain to prevent the device from exceeding the positive swing

limitation can be defined by the equation:

REF

SP

Shunt

MAX

V

-

V

Gain

R

I

<

×

×

(3)

Where :

IMAX is the maximum current flowing through RShunt.

Gain is the gain of the current-sense amplifier.

VSP is the positive output swing.

VREF is the externally applied voltage on the REF pin.

To prevent positive output swing limitations when selecting RShunt, a trade-off must be made between the

sense resistor value and the device gain. If the sense resistor chosen to satisfy the maximum power

dissipation is excessively large, selecting a device with a lower gain may be necessary to avoid exceeding

the positive output swing limit.

The negative output swing limitation defines the minimum allowable value of the sense resistor for a given

application. The limit on the minimum sense resistor value can be defined by the equation:

REF

SN

Shunt

MIN

V

-

V

Gain

R

I

>

×

×

(4)

Where:

IMIN is the minimum current flowing through RShunt.

Gain is the gain of the current-sense amplifier.

VSN is the negative output swing of the device.

VREF is the externally applied voltage on the REF pin. This voltage is zero for devices without a REF pin.

Besides adjusting RShunt and device gain, slightly increasing the voltage applied to the REF pin above GND

can help avoid negative output swing limitations.

9.3. Signal conditioning

In noisy environments, accurate current measurements typically require filtering of the current-sense signal.

The DIO2186 has low input bias currents, enabling adding a differential mode filter at the input without

sacrificing measurement accuracy. Applying filtering at the input stage is beneficial as it reduces differential

noise prior to signal amplification.

Figure 13. Filter at the input pins

To calculate cut-off frequency, refer to the equation below: