Make under shelf lights
Using tape LED
- LED tape warm white 5m 300LEDs 12V - Amazon \550
- 900 x 20 x 4mm Japanese cypress work board - DIY store \250
- Polycarbonate corrugated sheet frosted clear 1800mm - DIY store \1800
The LED tape can be cut every 5 cm and used. It has 3 LEDs in series and a 150Ω resistor. The voltage drop is about 3.2V.
(12 - (3.2 * 3))/150 = 16 [mA]
Dimming lights
I thought about PWM with PIC, ESP32, Raspberry Pi Pico, etc., but I found an LED driver that seems to be interesting, so I will try it.
Constant current LED driver with PWM (NJW4616U2) - Akiduki (5p \200)
An arbitrary constant current can be set with a resistor, it can be turned ON / OFF, and it does not generate heat like a transistor. It is a product introduction that seems to have a built-in PWM dimming function, but it is not attached. Input PWM with the ON / OFF pin. Built-in safety device.
# Reg(Ω) = 0.2 / I (A)
1.2 = 0.2 / 0.166
2.4 = 0.2 / 0.083
4.7 = 0.2 / 0.042
5.9 = 0.2 / 0.033 (4.7Ω + 1.2Ω)
7.1 = 0.2 / 0.028 (4.7Ω + 1.2Ω * 2)
When 7.1Ω is connected, it becomes 28mA constant current (it does not flow to this sense resistor). With 17 sets, it is a little 1.64mA per LED, but I want to suppress glare.
