Slew Rate for Inductive Load

[Sahara]

Hi to All,

I am looking for equation for Slew rate for Inductive Load and Resistive load. I want to find out Slew rate for DC power Supply

Please provide the equation if any one has.

 

[chuckey]

Passive components do not have slew rates. They have time constants. The current is given by some relationship to the applied voltage.
Frank

 

[Sahara]

Hey Frank,

i think, you misunderstood my question. I am talking about slew rate for dc power supply when it is connected to inductive load. I have found some equations for Slew rate with resistive load but unfortunately, still now sure about inductive load. some of articles talks about Capacitive load too,

 

[FvM]

i think, you misunderstood my question

I think, you didn't manage to ask a clear question, like
- my circuit is ...
- I want to know the slew rate of this value (voltage/current) ...

 

[chuckey]

If you suddenly place a highly inductive load on a PSU, the initial current will be zero and will ramp up exponentially to the final value of Vout/Rload. So its like like you putting a variable resistive load on the PSU and winding the knob on it very fast!. If your PSU cannot handle fast transient loads it will go into some form of oscillation and hopefully settle. A capacitive load act the other way, where the initial current is high, so the PSU might go into current limit and at the same time trying to actually increase the output voltage, which has bound to have dropped due to resistive losses times the large current. This is the critical slew rate limitation, i.e. how fast the PSU's amplifier can deliver current into the capacitive load. So with an amplifier with a limited slew rate, the output voltage will drop and only recover in the time of output current divided by the current slew rate.
Frank