SONOFF develops a lot of device for home automation. They have one product NSPanel which is nothing but a TFT Touch controller which has two switches in built and can also be used as a central controller for many more devices connected on the same network.
I got the opportunity to explore how it is designed and what all they have used inside. I am sharing so you can learn too.
As always the packaging is excellent and enclosure is also of very premium quality.
Front you will see a TFT touch display and two physical switches and on the back side terminal connection for Main Supply Input and load connections.
The construction of the device is such that power section and control section are kept separate ( display, controller and Wi-Fi)
When I opened the Power section, there I saw Power supply circuit where it uses LP3669 PWM isolated AC to DC converter. This section basically converts AC Voltage to DC using ABS8 bridge rectifier and then using LP3669 to 5V DC which is used for powering the MCU, Wi-Fi, Display section and Relay operation.
Other than power supply, two 5V DC Relays GI-1A-5LH (250V 10A) and its Mosfet based drive circuit is also included in this power section.
In the control section, you can see a TFT display. You can see a separate controller is used for Display. May be this is a Smart display so that full processing load doesn’t come on main controller.
Two switches, one NTC for temperature sensing and a switch for Reset in came MCU hangs.
and the other part is main controller with WIFI. ESP32-D0WD Wireless SoC is used along with ESP PSRAM16H (16Mbit) and NOR Flash 25VQ32. For WIFI PCB Antenna is there.
You can also see an SMD buzzer is used for audio alarm.
Two LDOs (ME6122A) are used on the control board for converting 5V DC to 3.3V, one for Wireless MCU.
I hope you found this teardown useful and learned something new today!
If you have any questions please ask in the comments section below, I will try to respond as soon as possible.
You can read other teardown blogs and watch teardown videos.
I am currently working as an embedded systems design consultant and helping companies build custom embedded products, develop test automation solution for their PCB or complete product.
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