DA9131 datasheet(20/56 Pages) DIALOG

20 / 56 page

DA9131

High-Performance, Dual-Channel DC-DC Converter for

Mobile and Portable Applications

Datasheet

Revision 2.0

11-Aug-2021

CFR0011-120-00

20 of 56

4.1.6

Resistive Divider

DA9131 can support output voltages higher than 1.9 V using an external resistive divider shown in

Figure 9.

To calculate the output voltage with an external divider, use the following equation

�� = �� × (1 +

��1

��2

)

Equation 1

VSEL is the device buck output voltage setting.

Figure 9: Resistive Divider

For example, to program the output voltage to 3.3 V, set VSEL to 1.65 V, and use a 2.2 kΩ resistor

for both R1 and R2, with Cff = 1 nF.

NOTE

The resistors need to be properly selected since the output voltage accuracy will be directly affected by any

errors on the resistors. The voltage across FB1P and FB1N (VSEL) is guaranteed, but not the output voltage

accuracy.

CAUTION

The followings are important notes that need to be considered before using resistive divider on DA9131:

1. Please contact your region's Dialog representative when adopting the resistive divider technique. Dialog

need to prepare a special OTP because incorrect OTP settings may result in a different output voltage

than expected.

The total resistance (R1+R2) is less than 40 kΩ.

3. It is recommended that the device is operated in PWM mode only.

DA9131 データシート(PDF) 20 Page - Dialog Semiconductor