ESP32 PICO D4 Power supply

[ravi_butani]

Hii I am using ESP32 PICO D4 Chip for my project which is powered by 1 cell Lipo (3.7V to 4.2V). For reduce BOM Cost I have decided to use two 2.8V 300mA LDO instead of single 2.8V 500mA LDO which is 5 time costly compared to 2.8V 300mA LDO. Here are my confusions..

1. Can I use 2.8V Supply voltage for all VDD pins without any problem ? (Datasheet suggest 2.3 to 3.6V range except VDD3P3_RTC and I am not using RTC)?
2. Which power supply (VDD) Pins are for RF part and Which are for CPU? So I can use one 2.8V 300mA LDO to power CPU and other 2.8V 300mA LDO to power RF Part of chip

Thanks in Advance for your kind suggestion on the same..

Cheers,
RAVI

[krzychb]

Hi ravi_butani,

1. Can I use 2.8V Supply voltage for all VDD pins without any problem ? (Datasheet suggest 2.3 to 3.6V range except VDD3P3_RTC and I am not using RTC)?

No. VDD3P3_RTC should be 3.0 V ~ 3.6 V , see ESP32-PICO-D4 Datasheet V1.7 - "Note that the embedded flash is connected to VDD_SDIO which is driven directly by VDD3P3_RTC through a 6 Ω resistor. Due to this resistor, there is some voltage drop on this pin from VDD3P3_RTC."

2. Which power supply (VDD) Pins are for RF part and Which are for CPU? So I can use one 2.8V 300mA LDO to power CPU and other 2.8V 300mA LDO to power RF Part of chip

- VDDA pins are for RF
- VDD3P3_CPU and VDD3P3_RTC are for CPU