DIY LED lamp modification, find the required resistance parameters.

Using a 5V500mA charger, select the resistor:

1: single 1W LED lamp with DC voltage of 3-3.3V and 350MA.

Available resistance: (5V-3.0V)/0.35A=5.7. In fact, 5.6~6.8 ohms 1~2W resistors can be used in series!

2: Single 3W LED lamp, DC voltage 3-3.3V, 600MA.

Available resistance: (5V-3.0V)/0.6A=3.3. In fact, 2~3W resistors of about 3 ohms can be used in series!

3: single 5MM straw hat lamp, DC voltage 3-3.3V, 20M.

Available resistance: (5V-3.0V)/0.02A= 100. In fact, the resistance of 0.25~0.5W can be connected in series 100 ohm!

4: single 0.5W straw hat lamp, positive 3-3.3V, 150MA.

Available resistance: (5v-3.0v)/0.15a =13.3 actual available resistance12 ~15ω 0.5 ~1w used in series!

Selection of lithium battery resistance;

1: single 1W LED lamp with DC voltage of 3-3.3V and 350MA.

Available resistance: (4.2V-3.0V)/0.35A=3.4. In fact, 3.3 ~ 4.7 ohms 1~2W resistors can be used in series!

2: Single 3W LED lamp, DC voltage 3-3.3V, 600MA.

Available resistance: (4.2V-3.0V)/0.6A=3.3. In fact, 2 ~ 3W resistors can be used in series!

3: single 5MM straw hat lamp, DC voltage 3-3.3V, 20M.

Available resistance: (4.2V-3.0V)/0.02A=60. In fact, it can be used in series with a 0.25~0.5W resistor of about 60 ohms!

4: single 0.5W straw hat lamp, positive 3-3.3V, 150MA.

Available resistance: (4.2V-3.0V)/0. 15A=8. In fact, 8 ~ 10ω0.5 ~ 1W resistors can be used in series!