Thanks for the scope shots JDB (or what ever your real name is) !
In this first picture I have 'zoomed out' to show the more of the cycle. The upper trace is the output from J1. The sharp edge is caused when the MOSFET Q2 is turned off, it is no longer possible to measure the inductor current.
Again, beginner's mistake, silly me.
The voltage across the inductor is the difference between the TP3 and TP4 waveforms. Again, this shows how the energy is recovered.
During the decaying period, once the inductor's voltage (minus diodes drop out) is equal to power supply rail, the inductor will self dissipate the rest of it's own excess energy through the ringing as observed at the scope shot, am I correct ?
Just curious and purely academical here, curious in ball park number on how much percentage of the energy left in percentage of total only at that ringing period ?
Still learning, hope you're not bored to death entertaining my noobness.
The current draw from the 10V power supply from this test was 0.058A, which is 0.58W and this includes all the power consumption in the gate drive circuitry.
I'm aware of the energy required to charge those big caps when the circuit was turned on for the 1st time, but lets ignore this initial state, from this result that this circuit draws only 58 ma at 10 volt is pretty low isn't it ? This is valuable info, so I don't need a beefy power supply.
Another question
Is it easy to separate the supply of the driver (inc the pwm generator) in the yellow shaded area from the green one at the below pic ?
The reason is, say for an inductor with high inductance and high current saturation, this will have a really slow di/dt or shallow loong trace, so the easier part is to crank up the supply voltage to speed up the di/dt, and vice versa like small inductor with low inductance that has really steep di/dt, reducing the supply voltage will make the measurement easier.
Of course there is a reasonable min and max test voltage for the inductor say like starting from 5 volt up to maybe 30 volt ? Or what ever range that you think is possible without over complicated your design ?
Thanks in advance, JDB.
PS : Suggesting you to attach any pictures at this forum like I did here, instead of using external hosting like the tinypic.com you're using, we never know what will happened in the future for this kind of hosting sites. An example what is happening with these so called "FREE" pic hosting site -> HERE.
Just use the attach feature right below the dialog box where you type your post.