Willen
Well-Known Member
The output , driver and pre-driver transistors need base to ground resistors to quickly turn them off.
All transistors needs resistor from base to ground, um....... Which is the value please!
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The output , driver and pre-driver transistors need base to ground resistors to quickly turn them off.
Use one 100 ohms for each set of four output transistors.All transistors needs resistor from base to ground, um....... Which is the value please!
Use one 100 ohms for each set of four output transistors.
Simply look at the circuit to see that the emitters are grounded and the base goes as high as the datasheet says it does. Only to 1.5V!- Then I need two 100 ohm resistor for two set of output transistor. May the resistor will be high watt like 5watt, isn't it? Or 1/2watt is fine?
Simply calculate the maximum power in each resistor. The 15 ohm resistor connects to 12V which might be 13.8V when the battery is fully charged and the 100 ohm resistor connects to two base-emitters in series making about 1.7V. So the 15 plus 100 resistors have 12.1V across them which makes their current (12.1V/115 ohms=) 105mA. Then the power in the 15 ohms resistor is only 0.166W and the power in the 100 ohms resistor is 1.1W. The resistors are powered for only half the total time so their actual average power is half. A 1/4W resistor is fine for the 15 ohms resistor and a 1W resistor is fine for the emitter resistor.Oh! remember about resistor watt, look at pre-driver, as you said it will not conduct more current then why there is 5watt at collector and 1 watt at emitter? Is it silly too? May I use normal 1/2watt?
Maybe.- Any transistor will work as Q3, Q4? Even 547, 549 too?
Yes.Maybe it's related to its hFE and I(c).
I do not know if your TV will work from an unregulated squarewave. Some do.- In maximum, how many parallel transistor can I use? (I think 'driver' is not able to drive ultimate numbers of transistors)
use simple arithmatic and the specs of the transistors.
(OK, I will use 12V zener, 0.1uF and 100uF. I am going to use it as a general purpose, to light bulbs, to watch TV etc. Here almost half of the time in a day and night is no electricity due to load scheding (lack). So. Ok i will modify as you say.)
An output transformer for which circuit?Dear AG,
Is it easy to make same Transformer as an 'output transformer' and same transformer as a 'Charging transformer'?
Any idea, any circuit? Searched few links but can't find!
The BC547 has a very wide range of current gain from 110 to 800. The CLAP circuit probably will not work with low gain transistors and the flip-flop transistors should be matched.
The BC547C is selected for high gain from 400 to 800 and will work.
Maybe the author built only one circuit and it worked because he was lucky to find BC547 transistors with high gain.