DIA2240

Version 1.1, Apr 2026

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© 2026 Dioo Microcircuits Co., Ltd. Jiangsu

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Table 3 provides the examples of gain error factor and gain error for different resistor values.

Table 3. Gain error factor and gain error (external input resistors)

External Resistance (Ω)

Gain Error Factor

Gain Error (%)

5

0.998

0.17

10

0.997

0.33

100

0.968

3.23

10.2. Typical application for inline motor current-sensing

Figure 18. Inline motor application circuit

In motor control, inline current sensing has many advantages, such as torque ripple reduction and real-time

motor health monitoring. However, the full-scale PWM voltage requirements for inline current

measurements bring challenges to the accurate current measuring. Switching frequencies in the range of

50 kHz to 100 kHz generate higher ΔV/Δt signal transitions, which must be addressed to obtain accurate

inline current measurements.

The DIA2240 provides performance for a wide range of common-mode voltages with a superior

common-mode rejection capability, high precision, and a high common-mode specification.

For inline motor current-sense application, the DIA2240 measures current with a 36 V, 4000 RPM motor.

To demonstrate the device performance, the DIA2240A with a gain of 20 V/V was selected for this design

and powered from a 5 V supply.

As mentioned before, the reference point is set to mid-scale by splitting the supply with one reference pin

connected to ground and the other one connected to supply, which allows for bipolar current measurements.

Alternatively, the reference pins can be connected together and driven with an external precision reference.

The output of the DIA2240 is not saturated because of the sized current-sensing resistor. To keep the

analog input within the device limits, select a value of 100 mΩ.