Measuring bipolar transistor ON resistance
I am curious about how to measure the ON resistance of a bipolar transistor (of which the datasheet does not specify) at varying Base to Emitter voltages, whereas MOSFET datasheets specify an ON resistance at a given Gate to Source voltage.
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Re: Measuring bipolar transistor ON resistance
The data is given you just don't know how to interpret it. The parameter you are interested in is Vce (sat) which is the static voltage drop of the bipolar transistor when it is saturated ie fully ON. Vce (sat) times the RMS current going thru the transistor, gives the power dissipation of the device.
As far as i remember (big bipolars are too slow for my taste so i don't work with them too often), in most datasheets there is also a Vce (sat) vs Ib plot. Same as Vgs vs Rdson for mosfets.Last edited by Th3_uN1Qu3; 03-27-2011, 08:48 AM.A working TV? How boring!Originally posted by PeteS in CA
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Hi guys, i was wondering, i've got 9Ohms on Vmem, one of the mosfet was shortet to ground, so i've desoldered hi and low mosfets nad still low res, then i removed all of the memory chips, and the resistance is still low, so did you had maybe a card with that low res on memories, and the card was working fine ?
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Resistance on 12V 4K ohms (Power present when on)
Resistance on 12V PEX 4K ohms... -
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Hello
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Good day all,
I have a question about some old monochrome Apple monitors.
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A friend replaced a bipolar 4.7uF 25V capacitor with a Nichicon bipolar 4.7uF 25V. The cap popped after about one hour. The new capacitor was much smaller than the original one but that's not a surprise as the original one was from 1980. (I am not sure whether the original was was actually 4uF and was replaced with a 4.7uF?)
The new capacitor:...
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