capacitor charging and discharging circuit

Hi

The relationship between capacitor voltage, capacitor value, current, charging is I = C*dv/dt . I need more details on what type of power supply or circuit you intend to use to charge and discharge the capacitor before I recommend a suitable IC from TI.

Regards

Peter

Peter,
I also am interested in an IC which can charge and discharge a 300-500VDC flash capacitor at a rate of 1-3 Hz rather than using a xenon flash tune. I will be using a 12vdc, 3A wall wort for supply. Any suggestions ? Thank You.

Hi Joseph,

It sounds like to you need an non-isolated boost device, 12V input 300-500v dc output. Nearly all the devices I cover are for offline ac/dc applications, like the 12V ac/dc you will use on the input.

TI has a non-isolated power forum which would be a better forum to place this request.

Regards

Peter

Ed,
Thank you for getting back.
I am driving a capacitor to discharge into a coil. I am trying to eliminate the use of a xenon tube, trigger coil etc. This is not a lighting application. The important part is to be able to charge a flash capacitor to 300-600VDC and discharge it at a rate which would deliver maximum voltage and current to a coil. Any supply voltage is acceptable.
Thank you for your time.

Joseph,
The TPS65560 would perform the function you are looking for.
For 12V to 600V stepup you must use a Flyback topology.
The transformer turns ratio determines the output voltage.

TPS65560 has a flyback first stage which provides the control to create the high voltage.
Referring to the data sheet, Figure 1, T1 is the flyback transformer.
It is switched on the primary by the TPS65560 internal fet.
Output energy is stored in Co, the output capacitor after D1

Then it has a 2nd function of controlling an external high voltage IGBT to apply Cout to the load.
The load in this case is a Flash bulb.
However the IGBT switches the primary of a 2nd transformer, a coil, for the much higher firing voltage.

So it is driving a coil, as you want to do.

Ed,
Thank you again. I am presently using a flash circuit with a xenon tube to power an external coil. The external coil is connected to the discharge of a flash capacitor (Co) and the other end of the coil is connected to the + of the xenon tube. I am trying to eliminate the xenon tube and trigger. The objective is to charge and then discharge the flash capacitor (Co) through an external coil with as few external components as possible.

Well Joseph, there are surely infinite ways to do the function with some discretes. But I don't know what would be gained by going away from an IC solution like the TPS65560. In order to make the lamp firing work the coil needs the di/dt that a switch provides. V=Ldi/dt for a coil, without the fast rise of current di/dt of the switch then the coil will not make V.

Seems that the IC would be the lowest parts count.

This post should reside in the LED Driver Forum so I will move it there.

May I mark this post closed or do you still have more questions?