不管是什么状态,在此电路中,进去的信号就只有LAN_ON信号作为EN开启。没有别的信号,,除了信号就2个电压,VCC=5V一直没变,变的只是VIN,用适配器时19V,用电池12V。
还有MOS管上管D极电压同VIN。
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查过ISL6227的VIN脚,好像是一个多功能脚。英文如下。
VIN (Pin 14)
This pin has multiple functions. When connected to battery voltage, it provides battery voltage to the oscillator as a feed-forward for the rejection of input voltage variation. The ramp of the PWM comparator is proportional to the voltage on this pin (see Table 1 and Table 2 for details). While the DDR pin is high in the DDR application, and when the VIN pin voltage is greater than 4.2 volt when connecting to a battery, it commands 90° out-of-phase channel synchronization, with the second channel lagging the first channel, to reduce inter-channel interference. When the pin voltage is less than 4.2V, this pin commands in-phase channel synchronization.
用google翻得不好,还是看得不太懂。作者: jzfs 时间: 2011-5-22 00:04 这个翻得是很不好。作者: 雨夜天空 时间: 2011-5-22 20:17
新情况,我把L512(到网卡),Q10(+V1.2L转成+V1.2S)拆了后,电压出来了,量了一下,L512和Q10都正常,原样装回去。电压还是正常出来了。怎么回事?
上次也好过一阵子,也是拆了一些元件后又装回去就好了。
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还有就是那0.34V的电压不是ISL6227产生的,是+V1.2S那倒流过来的。