Kapanadze Cousin - DALLY FREE ENERGY

[Jeg]

Great tool for experiments magpwr. Thanks for sharing. 

[Ed morbus]

magpwr
Thanks for sharing

[John.K1]

Sorry guys, I know it was here before,I just took the KA7500 out of my drawer.

Can somebody tell me what resistor and Capacitor I should to change to get different frequency than the defoult ( which is 33KHz).

Also, I am not sure if I understand right how to use it. Is this actually the device I can strait way connect to mu yoke ( I guess it is not - possibly not enough protected ?)or should I use it just with gate drivers and Power Mosets??

I checkesd it on scope  both PWM pins. One of the PWM square is slightly bigger than the other. In other words when PWM_1 goes off there is still some time delay before the PWM_2 goes ON. Is that normal?

Thank for your help.

[Void]

Sorry guys, I know it was here before,I just took the KA7500 out of my drawer.
Can somebody tell me what resistor and Capacitor I should to change to get different frequency than the defoult ( which is 33KHz).
Also, I am not sure if I understand right how to use it. Is this actually the device I can strait way connect to mu yoke ( I guess it is not - possibly not enough protected ?)or should I use it just with gate drivers and Power Mosets??

Hi John.k1. If you can identify pins 5 and 6 on the KA7500 chip, according to the KA7500 spec sheet,
the resistor connected to pin 6 and the capacitor connected to pin 5 are used to set the frequency.
See page 3 in the following KA7500 spec sheet:
https://www.fairchildsemi.com/datasheets/KA/KA7500C.pdf

Some info on your KA7500 board on ebay states the following regarding Rt and Ct possible values:
"Changing the timing components Ct, Rt parameters can be easily changed PWM output frequency.
R(t) ranges from 1.8~500kΩ, C(t) ranges 4700pF~10μF, the maximum oscillation frequency (fOSC) ≤ 300KHz."
http://www.ebay.com/itm/TL494-KA7500-DC-9V-25V-Driver-Board-DC-DC-Converter-Inverter-Boost-Module-PWM-/111850697617?hash=item1a0ad23391:g:FBIAAOSw3KFWcAMd
The spec sheet says it can be used to a max frequency of 200 kHz, but in the Description section they say 300 kHz.

I would guess that you would have to connect outputs PWM1 and PWM2 to MOSFET drivers and then
from there to some driver MOSFETS.

[TinselKoala]

The photo shows a TL494, does it not? I don't know how precisely equivalent the 494 is to the KA7500, but pins 5 and 6 control the timing just as Void has said.

The "dead time"  is controlled by an input to Pin 4 on both types.