Hi
I need help designing a simple over and under voltage protection circuit. I am connecting my 12V lead acid motorcycle battery directly via its terminals to Arduino and ESP32 module, while the bike is operational
Battery voltage varies between 9-16V when running.
Transients can be upto 100V.
This is the circuit I plan to make
12V motorcycle battery → Over-voltage protection → LM2596S SMPS → Arduino Nano → ESP32
Kindly help me design a basic circuit.
I am a beginner in electronics.
Good day @vikram9447,
You may consider using 1738-1293-ND as a prebuilt LM2596S SMPS that you can adjust to drive your Arduino and ESP32 module. (Adjust the voltage before attaching them to the SMPS output).
I’d add a TVS (Transient Voltage Suppressor) 283-6KPE20CAHCT-ND across the +12V and GND of your SMPS to snub those 100v spikes.
Having it all in a weather proof container will help too.
Kind regards,
Brian
Hi Brian_German
Thank you for responding.
My maximum current draw would be 2A.
I am definitely using the LM2596S but w.r.t. the TVS diode, it is slightly expensive for my needs as of now. Can I use this instead:
Source video for the schematic: Transient Voltage Input Protection / MOV - YouTube
That zener clamp with schottky/schmitt trigger would be an effective method of taking the 12V signal and inputting it into a digital input pin of a microcontroller.
What I would be concerned about is those transients getting to your power supply. The LM2596 can take a maximum of 40VDC.
Technical Article on Transient Voltage Suppression in Automotive from Diodes Inc
What is normally used for transients from an alternator is a zener TVS diode like Brian German suggested.
Another example part number would be F7638CT-ND
