LED接入笔记本的方案

来源：百度知道 编辑：UC知道 时间：2024/05/29 09:59:31
我想把25颗LED灯并联接入笔记本的USB接口.
如果有一个LED灯坏了.其它的会有什么情况?
如果有一条线路断开了.这样就等于只有24个并联.越来越少后.会不会电流过大击穿LED灯.或是烧掉USB?
寻求一个可以接入笔记本的方案.笔记本电源输入的是20V 6A
USB接口输出电源是5V 500MA
接哪个比较安全.要以电脑主板的安全为前提

首先你的24个LED应该是串联+并联,在5V电压下应该是每三个为一组并联,共7组然后将他们串联(给你省了4个),后接入USB,总电流应该在280-350mA,这样使用比较安全,当其中一个开路后,同组的应该比较容易损坏,直到一组全部烧坏后全部不亮.

When wiring an LED you have three options

* wire each LED single with its own resistor
* wire multiple LED's in Series with a single resistor
* wire multiple LED's in Parallel with a single resistor

Single-

For an example we will use a single Ultra Bright blue 5000mcd 3mm LED.

Our supply voltage will be 5V from USB (could be 12V or whatever supply you are using)
The LED has a voltage drop of 3.3V
The LED should run at 20mA

Plug those values in the resistor calculator and see what you get

Calculated to exactly 85 Ohm
next highest 10% resistor 100 Ohm
0.034 WATTS
0.057 WATTS safe pick*

*safe pick means you should have a buffer over the minimum, in reality you can run a much higher wattage resistor without issue most readily av