DIO2240

Version 1.2, Jan 2026

www.dioo.com

© 2026 Dioo Microcircuits Co., Ltd. Jiangsu

9

increases the current-sensing resistor value. Larger resistance value, larger power dissipation in the

system, which can additionally results in the decreased overall system accuracy. Therefore, the

measurement accuracy is inversely proportional to both the resistance value and power dissipation

contributed by the current-shunt selection according to the relationships mentioned above.

The differential voltage is increased across the resistor when the current-shunt resistor is increased. To

achieve a full-scale amplifier output voltage, larger input differential voltages require a smaller amplifier gain.

Although larger amplifier gain settings are needed, smaller current-shunt resistors are preferred. Larger

gain settings often result in higher noise and error factors, which makes them unsuitable for precision

designs. Historically, larger current-sense resistors and lower gain amplifier settings have been required for

the design of high-performance measurements. The DIO2240 provides 100 V/V and 200 V/V gain options

that offer the high-gain setting, and at the same time it maintains high-performance levels with low offset

values. Lower shunt resistor values can be used to meet lower power dissipation and high system

performance specifications at the same time.

An example of the different results of two different gain versions (20 V/V and 200 V/V ) is shown in table

below. The higher gain device allows a smaller current-shunt resistor and decreased power dissipation in

the element. Except for the gain and current-shunt value, the error calculations must also be considered.

Table 1. RSENSE selection and power dissipation

Symbol

Parameter

Equation

Results

DIO2240A

DIO2240D

Gain

/

20 V/V

200 V/V

VDIFF

ldeal maximum differential input voltage

VDIFF = VOUT / Gain

150 mV

15 mV

RSENSE

Current-sense resistor value

RSENSE = VDIFF / IMAX

15 mΩ

1.5 mΩ

PRSENSE

Current-sense resistor power dissipation

RSENSE × IMAX 2

1.5 W

0.15 W

Note:

(1) Full-scale current = 10 A, and full-scale output voltage = 3 V.

9.3. Function mode

9.3.1. Adjusting the output midpoint with the reference pins

A test circuit for reference-divider accuracy is shown below. The DIO2240 output allows for unidirectional or

bidirectional operation.

Figure 11. Test circuit for reference divider accuracy