ESP32 + RPi Zero - a correct approach?

[chitester]

Want to seek recommendations from the forum about developing a low cost IOT device. The IOT device needs to have a HDMI port and WiFi, and to be produced as lowest cost as possible. RPi Zero W should be the ideal candidate. But unfortunately, for whatever reasons, RPi Zero W is not FCC certified as a modular (RPi 3A and 3B are FCC certified as modular).

If I use ESP32 (FCC certified as modular) as a WiFi module for RPi Zero, the cost for both boards are still below USD 10. RPi Zero will send AT commands to ESP32 to have WiFi access. Does this arrangement make sense technically and economically?

[DougieLawson]

The RPi Zero with on-board WiFi is a better option. Keep the esp32 as a remote sensor driver that can publish on an MQTT topic.

[drgeoff]

If I use ESP32 (FCC certified as modular) as a WiFi module for RPi Zero, the cost for both boards are still below USD 10.

The RPi Zero is not available in quantity at a unit price equal to or below US$5.

[chitester]

The RPi Zero with on-board WiFi is a better option. Keep the esp32 as a remote sensor driver that can publish on an MQTT topic.

It is a better technical option but not for business purpose. Because RPi Zero with on-board WiFi is not FCC certified as a modular. I will make my own PCB. This means that before I can sell a single unit of IOT device, I need to pay a couple thousand USD for FCC certification.

[chitester]

If I use ESP32 (FCC certified as modular) as a WiFi module for RPi Zero, the cost for both boards are still below USD 10.

The RPi Zero is not available in quantity at a unit price equal to or below US$5.

You are right. Some distributors forced me to buy their kits. This is a real problem.

[chitester]

After reading more posts about the severely restricted availability of RPi Zero, my conclusion is to use RPi 3A+. This will increase the BOM cost about USD 15 ($10 more for RPi A comparing to ESP32+RPi Zero, and $5 more for a 3A 5V power adapter (comparing to a 1A power adapter)). This will make the retail price at least $60 more (100% gross profit margin and 100% retailer margin). Sigh, the business plan is not sustainable anymore.

[fruitoftheloom]

After reading more posts about the severely restricted availability of RPi Zero, my conclusion is to use RPi 3A+. This will increase the BOM cost about USD 15 ($10 more for RPi A comparing to ESP32+RPi Zero, and $5 more for a 3A 5V power adapter (comparing to a 1A power adapter)). This will make the retail price at least $60 more (100% gross profit margin and 100% retailer margin). Sigh, the business plan is not sustainable anymore.

The Zero & ZeroW are sold at virtual cost price so they can be available as a low cost option to aid Education and Learning, they are not sold for Businesses to make a profit.


If you order a few thousand bulk you can buy at a higher price, it has always been that way.

Also the Zero family is not guaranteed to be available long term, the Compute Module has at least 4/5 years availability and has been used in many retail products.....

[Andyroo]

Without knowing details of your device I would ask yourself do you need all the power of a Pi or rely on an SD card to make the device work? If the first is yes and the later is no then the compute module has to be the choice.

I would have though that you just need to turn the device on and have it work day in and day out - sometime we love the Pi so much it can get squeezed into projects it’s not suitable for. Discrete Arduino based modules can be found in bulk with FCC clearance and may be a better option.