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PCB power layout ESP32WROOM
Posted: Tue Nov 05, 2019 9:07 pm
by IBABBLED
We are moving from the ESP32 Dev kit board to our own board and need a PCB layout for the power pins. Can anyone forward?
Questions:
1. Does input power source need to be in the range of 3.0V - 3.6V?
2. What does the A range have to be?
3. Do you have to connect to power both PIN2=3V3 and PIN 3=EN for a basic design?
Thanks.
Re: PCB power layout ESP32WROOM
Posted: Wed Nov 06, 2019 9:06 pm
by IBABBLED
Additional clarification.
I need help verifying the required external components for powering the ESP32-WROOM-32D module as well as the input power and amp range required.
I found the following reference for the external components required.
- PIN2 (3V3) connects to VDD33 via C1 and C2
- PIN3 (EN) connects to VDD33 via C3 and R1
If this is correct:
1. What are the smallest acceptable footprints sizes for C1, C2, C3 and R1 (e.g. 0603, 0402)?
Specifications for VDD33:
1. Is it required for the input voltage and current be 3.3V and 500mA?
2. What range is acceptable for both?
Re: PCB power layout ESP32WROOM
Posted: Thu Nov 07, 2019 10:01 pm
by martinayotte
IBABBLED wrote: ↑Wed Nov 06, 2019 9:06 pm
1. What are the smallest acceptable footprints sizes for C1, C2, C3 and R1 (e.g. 0603, 0402)?
For R1/C2/C3, yes, it could be 0603 or 0402, but for C1, since it is 10uF, I doubt ...
Re: PCB power layout ESP32WROOM
Posted: Fri Nov 08, 2019 4:37 pm
by IBABBLED
I've received information from ESP directly and several other sources. Here's what we believe the answer to be. Posting in hopes it will help others in the future.
Refer to two documents:
1. esp32-wroom-32_datasheet_en.pdf, page 13, Figure 3 - Schematics (outlines the chip VDD outputs and CAP values)
2. esp32-wroom-32_datasheet_en.pdf, page 14, Figure 4 - Peripheral Schematics (outlines the module outputs and CAP values)
We've confirmed from ESP the following values: (X5R or X7R is a must)
1. C1 - MLCC 10uF 6.3V X5R 20% SMD 0402 (ex. MURATA, GRM155R60J106ME15D)
2. C2, C3 - MLCC 0.1uF 10V X5R 20% SMD 0603 (ex.YAGEO, CC0201MRX5R6BB104)
3. R1 - Thick Film 10Ko 50mW 5% 0603 (ex.BOURNS, CR0201AJW-103GAS)
You've got some decisions with the EN pin output. We took the simple route and tied it to VDD. Hope this helps.
Re: PCB power layout ESP32WROOM
Posted: Thu Nov 21, 2019 10:33 am
by ESP_Sprite
Erm, from what I remember tying EN to Vcc is not allowed; the ESP32 needs to be reset on power up. You're better off using a RC network there; it's not like those 2 components will cost the world.