Other Parts Discussed in Thread: LM5017
Tool/software:
Hello:
Can the LM3150 be used to drive a coupled inductor ?
If so, can it have a "step up" conversion from 36 to 120V at 200W?
As if it was a "flyback" converter? But not a "std flyback" with a few kHz BW.
If you follow our discussions here in the Forum recently, we are looking for an isolated 36v input to output 100V / 200W converter but with a very fast response loop. You can see why in the Forum discussions.
COT is one such method.
Clearly, the switch must be external.
The controller also must be able to change output voltage fast enough so that the load sees a "flat top" very high pulse current with low duty cycle. So that average power output is 200W.
This means the output voltage has to track the sensed current pulse "envelop" & keep it with "flat top" during the pulse time. That is 400usec.
DC feedback with a slow current sensor won't do it. Because current pulse would droop for sure.
We do have a very fast current sensor.
LM5017 would have done the job but it has internal low power low voltage switches.
Hence interest in LM3150 but it is billed as "buck" controller with COT.
Yet it is not unusual to transform such a controller to drive a coupled inductor.
Then our plan is to change Vref pretty much as you would do in a Class D audio amp-- change Vref to change Vout thus a fast tracking of the current sensed by deriving a voltage from the sensed signal.
So we need an external Vref pin!
Which is not in LM 3150 .
One could think of using RTT8811B-00 from Richtek...they have no contact in the US...and we prefer full support for such tough problems..hence TI is first & perhaps the only line of defense!
What other nodes do we have to track the 100v output envelop over 400 usec?
Any comments would be of great value to us.
-r
