Fingerprint Sensor AS608 - A Beginner's Guide
One touch can replace keys. This project uses an optical fingerprint sensor to enroll users and then grant access with a quick scan.
read tutorial →
If you're looking for a simple battery protection board for your project, here's one for you. This board is based on the BM3451 chip. It handles 5 18650 battery in series or a total of 18.5V. It also has external bleeding for cell-capacity preservation. This prevents pressure on an individual cell leading to a longer battery lifespan.
Features:
- Suitable battery: 3.7V 18650 Lithium battery or polymer battery
- Charging Voltage: DC21V CC/CV
- Instantaneous current: 15A±2A
- Continuous current: ≤10A
- Charging current: ≤5A
- Overcharge detection: 4.25±0.025V
- Overcharge recovery: 4.15V±0.025V
- Over discharge detection: 2.8V±0.05V
- Over discharge recovery: 3.0V
- Resistance: less than 20mΩ
- Short circuit protection: protect and automatic recovery
- Recovery mode: Automatic recovery
- Size: 53mm x 18mm x 4mm
Manila stock. Order before 16:00 PHT, ships today via J&T or LBC. Provincial: 1–3 working days.
Schools / class POs: we accept Purchase Orders for accredited schools and universities. contact us with your PO details.
Returns: 7-day inspection window for DOA units. Email proof of issue and we ship a replacement.
Customers also bought
Build with this board
Thumb Joystick - A Beginner's Guide
Wire a joystick to your Arduino, read X/Y, then print UP / DOWN / LEFT / RIGHT to the serial monitor.
read tutorial →Motor Drive (BTS7960 43A) - A Beginner's Guide
Bench-test a 43 A motor driver before wiring the full project. Catches weak power, mis-pinning, and dead boards before they cost you time.
read tutorial →Raspberry Pi Pico (RP2040) - A Beginner's Guide
Coming from UNO and the Pico won't show a COM port? Here's the BOOTSEL trick, the driver fix, and the first sketch that actually works.
read tutorial →Notes from the bench
Ask the community
Project Showcase — show what you built
Share what you built. Photos, BOM, what worked, what didn't.
view thread →How to ask a good question (and actually get answers)
Symptom + what you tried + clear photo = answers within hours.
view thread →ESP32 brownout when wiring a sensor — fixes that worked
Brownout reset when adding a sensor? Notes on supply decoupling and GPIO checks.
view thread →First Arduino — sketch upload error, what to try?
Upload failing on your first Uno? Driver, COM port, board match — checklist inside.
view thread →