PMOS VGS 電壓

alan5438

請問各位大大一個問題,為什麼當輸入到48V時,Q4 VGS(+- 25V),為什麼Q4沒燒毀, D8沒用穩壓二極體,而是用SK5100沒事,不了解,請求開示......
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2 @' S7 T& O7 yQ4-> PMOS CEM6405
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D8-> SK5100

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huo_xing

alan5438 发表于 2025-11-21 17:17
2 R" P4 ?+ e6 U0 Q  k1 F也是,那換成穩壓二極體,是不是比原來方是好ㄋ....謝謝狗大

" I) n, w* f) v& O& P, g7 |正常设计是稳压管，18V左右。看你这个图也是稳压管，有没有可能是你弄错了，出货的东西贴的就是稳压管？
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alan5438

超級狗 发表于 2025-11-21 15:55
絕對的風險！
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. D5 A/ F/ Y7 K/ w7 S但只要出完貨就不干你的事，可以不予理會！

也是,那換成穩壓二極體,是不是比原來方是好ㄋ....謝謝狗大
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超級狗

alan5438 发表于 2025-11-21 15:15
# [$ }+ p" C+ q3 ]9 \6 g* g請問狗大,這樣使用方式還是有風險,故建議換成穩壓二極體(穩在+-25以內是嘛)

絕對的風險！

但只要出完貨就不干你的事，可以不予理會！
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alan5438

超級狗 发表于 2025-11-21 11:35
7 U! c5 N6 [1 A& \絕對最大額定限制（Absolute Maximum Rating）是以壽命（Life Time）及可靠度（Reliability）當觀點，超過 ...

請問狗大,這樣使用方式還是有風險,故建議換成穩壓二極體(穩在+-25以內是嘛)

超級狗

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) ]- Q, b1 B' y+ P, T  P絕對最大額定限制（Absolute Maximum Rating）是以壽命（Life Time）及可靠度（Reliability）當觀點，超過絕對會提早往生。

' {; X' C# [) C% @0 H3 h" b但沒說會馬上往生，也沒告訴你多久以後會往生。夠膽識的話，就繼續用到出事！

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超級狗

日寇 脫序八（Toshiba）半導體
4 c' ^+ \+ |, yWhat are the items for the absolute maximum rating in technical datasheet of the diode?
Absolute maximum ratings are the maximum values that must not be exceeded even momentarily to guarantee the life and reliability of the device. It mainly regulates voltage, current, temperature, etc.
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What are the items for the absolute maximum rating in technical datasheet of the diode? | Toshiba Electronic Devices & Storage Corporation | Asia-English
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超級狗

亞德諾導導體（Analog Device）
+ i8 a: ?; s& \An IC's absolute maximum rating is the limit of the conditions under which it may be operated. Operation beyond these limits will damage it, and may destroy it.（可能被摧毀）

How far beyond the limits is never stated. Some devices are very robust, some are not, but no manufacturer will provide support for deviation from the limits. The only safe rule is to treat "never" as never. But understanding why exceeding absolute maximum limits can cause damage allows us to design better systems.

https://www.analog.com/en/resources/analog-dialogue/raqs/raq-issue-19.html
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超級狗

諾迪克半導體（Nordic Semiconductor）
Maximum ratings are the extreme limits to which the device can be exposed for a limited amount of time without permanently damaging it. Exposure to absolute maximum ratings for prolonged periods of time may affect the reliability of the device.
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https://docs.nordicsemi.com/bundle/ps_npm2100/page/chapters/abs_max_ratings/doc/abs_max_ratings.html
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