Hi, I'm trying to control an NPN and a PNP transistor (2222A and 2907A respecitvely) at the same time so that when one is on, the other is off.
They are both connected to a 12V circuit.

As such I (hope) that delivering 12V will switch the PNP off and the NPN on, and that delivering 0V will turn the PNP on and the NPN off.

However, I need to control this arangement with a 5V TTL logic circuit.

Thus my dilemma is to create a (transistor. I considered relays but they are too big physically) circuit that will deliver 12V if given a 5V (high) TTL signal and 0V if given a 0V (low) TTL signal. Alternately, giving 12V when low and 0V when high would also be great.

Someone suggested using a 4427 Mosfet-Driver chip, which seems to be a fantastic idea, except that they're almost impossible to come by in Australia without paying 4 times their worth in shipping. So if anyone could help me create this circuit I would be forever indebted.

Thankyou
- Plex

 

The problem with this circuit is that there is a current spike thru the two output transistors at the switching time, but the transistors will survive that.

Attached Images

switch_176.jpg (42.4 KB, 324 views)

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