BIPOLAR ALTERNATIVE TO H BRIDGE

[Carl-NC]

Technically it is a form of PI but requires an IB coil. It transfers the magnetic field energy onto the coil capacitance as an electric field energy, then immediately reverses the process to the opposite direction. No damping resistor is needed because there is no free-running oscillation to dampen. That is, the coil is always driven and never left open.

The diode is just a protection device to prevent unwanted spikes (during the transitions) from zapping the preamp. If you could make a perfect IB coil then they would not be needed.

[Haydar]

Is this design for a PI system or an IB system? Could you explain how it works without a damping resistor? I don’t understand. Also, you clipped the signal going to the RX stage at 0.7 V using a 1N4148. What would happen if we raise this 0.7 V threshold?

[JoyJo]

It is interesting to be able to work on a single frequency, but so that you can also get a multi-frequency mode.

[moodz]

You could isolate it by two caps but do you want multi frequency?

[JoyJo]

Do you mean that the connection of the TX coil is the same as in a full H-bridge? And connecting the TX cactus to the device unit via a differential cable: two strands twisted together?

[moodz]

Can it be used without a matching transformer: only the CCPI and the TX coil?

Yes if you are prepared to use a balanced TX coil ( ie non grounded TX ... differential drive shielded pair )

[JoyJo]

Can it be used without a matching transformer: only the CCPI and the TX coil?

[moodz]

Short answer is yes.

[JoyJo]

And is it possible to use the CCPI TX cascade to work with the receiving tract of the VLF? The TSCI is an alternative to the full H-bridge. The H-bridge works in VLF systems.

[Carl-NC]

Yes, higher efficiency since it recycles flyback energy. Also faster as it requires no damping. Also bipolar which (a) eliminates the need for EFE samples and (b) improves EMI immunity. Also CCPI which allows for much faster pulse rates. This approach requires an IB coil which potentially makes the RX circuit a little easier. See the AMX project for an example design.

[bishop_slayer]

I just came across this. Can anyone confirm that the main advantage of this circuit is that it has a higher efficiency than a standard pulse generator in a PI detector? Or are there additional advantages? What implications does the bipolar pulse have on the electronics in the amplification chain? Has anyone developed a proper amplification circuit for the Rx pulse for this yet?

[Riss]

This bridge works fine, BUT! , M3 and M4 ( #1 ) must be replaced with p-channel mosfets to enable the bridge to operate at higher supply voltages. moodz to tell how to throw away (but not exactly like )M1 and M2, because I'm uncomfortable - after all, the idea and the thread are his property

[moodz]

Pair this with the zero point active damping and you have very nice combo right there.

Dont tell anyone

[Altra]

Working Thanks

[moodz]

... corrected sim file.

CCPI_REGULATED_V1 (2).zip

moodz