LPC55S26JEV98 || Power Supply

[JyotiVaishnav]

Hello Team, 

We are using an LPC55S26JEV98 processor in our design. 

Following below mentioned connections we did in our design for power rails.  
VDD_1 / VDD_2 / VDD_3 / VDD_4 - are connecting to 1V8 
VDD_PMU / VDDA / VBAT_DCDC / VBAT_PMU - are connecting to 3V3 

We want to know that there is any problem or issue to connect VDD_PMU / VDDA / VBAT_DCDC / VBAT_PMU the mention supplies to 3V3 voltage level. 

[xiangjun_rong]

Hi,

As TwoBias said, for the VDD_PMU power supply pin, we suggest you use internal DC/DC converter for the VDD_PMU power supply as the following Fig. The VDD_PMU power supply input voltage is from 1.1V to 1.2V, which can be controlled with software based on the core frequency.

It is okay that

VDD_1 / VDD_2 / VDD_3 / VDD_4 - are connecting to 1V8 
VDDA / VBAT_DCDC / VBAT_PMU - are connecting to 3V3 

Hope it is helpful

BR

XiangJun Rong

[TwoBias]

Hi,

you should not connect VDD_PMU to 3,3V.

It is core supply and maximum voltage is 1,26V.

You should connect it with the DCDC output path and FB Pin.

BR