找了点资料，放这里，让有兴趣的朋友也看到： Your PSU outputs +5 on a specific pin (+5VSB) when ever it's plugged in and turned on. This voltage is used to power your motherboards power control circuitry so that i can turn on when the BIOS tells it to, or when you press the button. The power button is nothing more then a momentary SPST push button switch . When you press it, your motherboard's power control circuitry connects the PS_ON lead to ground, then the PSU turns on fully up and provides power to all pins. Then it sends a Ready signal to the motherboard once it is fully powered up, so that the system only starts after the PSU is ready. You can replace/mod your PSU switch with anything that will provide a momentary connections of two contacts. Lamptron and Bulgin both make lighted vandal proof push buttons that just look bad ass... ============================ yep, just a momentary SPST (single pole, single throw) switch I just bought two spst momentary toggles (OFF-(ON)) from mcmaster-carr for the case mod project I am doing for my daughter. I am going to wire the new switches into the Power and Reset button circuits. Basically the new switches act as a circuit breaker so when the compuer is on my daughter cant do anything by pressing reset or power. In order for them to function you need to hold ON the secondary switch for that circuit, which are being installed on the back of the case (my daughter is 2). When my wife turns on the computer, she'll reach over and hold up the power toggle, then press the fron case switch like normal, then release both - same goes for reset if need be =============================================== The tec here uses a screw driver to compleat the cercut. It only needs contsct tween the 2 pins for a moment. I bought a cheep switch here to mod into the back for about 2$. ================================================= The actual switching of the power (on and off) is done by circuits on the motherboard. The circuits are triggered to change state by a momentary short circuit of two points in the circuit . That is done by the front panel push button. A short-term connection of that button is enough . The motherboard circuit also has a second and third function it can do. The BIOS usually is set so that, if the circuit is already on the ON state and the momentary contact is kept closed for at least 4 seconds, one of two actions will be carried out. Either the system will shut down right away (like turning off a switch), or the motherboard will enter the "sleep" state and wait to be re-awakened. Which of these two options is done is something you set in the BIOS Setup screens. This is the reason that the motherboard is never entirely "Off" in most operating situations. Even when it is "Off", there is a small portion of it devoted to checking for inputs from a few sources (like the front push button, some USB devices and maybe a modem) so that it can respond by turning power on to the entire system. The way to really shut down all power is either to pull out the power cord, or to use the physical switch mounted on the back of the PSU to switch it off. ======================================================== 果然只是一个短脉冲，不是电灯开关那样的长时间接通的。那我现在那个拨动开关就用错了。 S.P.S.T. normally-open, momentary pushbutton switch 弄个这个按钮吧： http://www.frys.com/product/2874744?site=sr:SEARCH:MAIN_RSLT_PG
标签: 台式电脑
