not a rock star, by most estimates just a prophet
You've all been asleep, you would not believe me
Them voices tellin' me, you will soon receive me
Standin' on the beach, the sea will part before me
Fire wheel burning in the air!
You will follow me and we will ride to glory, way up, the middle of
the air!
And I'll call down thunder and speak the same and my work fills the
sky with flame
and might and glory gonna be my name and men gonna light my way.
You've all been asleep, you would not believe me
Them voices tellin' me, you will soon receive me
Standin' on the beach, the sea will part before me
Fire wheel burning in the air!
You will follow me and we will ride to glory, way up, the middle of
the air!
And I'll call down thunder and speak the same and my work fills the
sky with flame
and might and glory gonna be my name and men gonna light my way.
Attachments
Is Fred The Swedish Chef?
Well let's see...........................
http://www.muppetworld.com/cooking/
😀 😀 😀
Jam
Well let's see...........................
http://www.muppetworld.com/cooking/
😀 😀 😀
Jam
Attachments
Re: More confused than I thought......
Since there's two major low-frequency poles (one from the op-amp and one from the pass transistor output resistance and load capacitor), the phase lag of the loop gain is 180 degrees at frequencies much higher than the second pole. Then you hit the series resonant frequency of the load capacitor which is about 100 kHz. At that frequency, the phase lag of the loop gain is about 90 degrees because the load capacitor is purely resistive there. If you run the pass transistor at low currents, the pole due to the load capacitor and pass transistor becomes lower in frequency, reducing the unity loop gain frequency accordingly. This can cause the phase lag at the unity loop gain frequency to get larger because you haven't seen all the benefits of the reduced phase lag due to hitting the series resonant frequency of the capacitor yet. A further effect happens due to the reduced ft of the pass transistor at low currents. This causes the output inductance of the pass transistor to increase, which can cause a really nasty increase in phase lag because of its interaction with the load capacitor.
At any rate, that's what I saw when simulating a +90V version of this thing with a Darlington configuration for the pass transistor. The transient response to a step of load current sucked at low currents due to the poor stability margin.
Fred Dieckmann said:
Since there's two major low-frequency poles (one from the op-amp and one from the pass transistor output resistance and load capacitor), the phase lag of the loop gain is 180 degrees at frequencies much higher than the second pole. Then you hit the series resonant frequency of the load capacitor which is about 100 kHz. At that frequency, the phase lag of the loop gain is about 90 degrees because the load capacitor is purely resistive there. If you run the pass transistor at low currents, the pole due to the load capacitor and pass transistor becomes lower in frequency, reducing the unity loop gain frequency accordingly. This can cause the phase lag at the unity loop gain frequency to get larger because you haven't seen all the benefits of the reduced phase lag due to hitting the series resonant frequency of the capacitor yet. A further effect happens due to the reduced ft of the pass transistor at low currents. This causes the output inductance of the pass transistor to increase, which can cause a really nasty increase in phase lag because of its interaction with the load capacitor.
At any rate, that's what I saw when simulating a +90V version of this thing with a Darlington configuration for the pass transistor. The transient response to a step of load current sucked at low currents due to the poor stability margin.
Swedish Chef
Hi,
I have a hard time understanding the Swedish Chef. My knowledge of the Swedish is nill and the Swedish Chef is hard to understand. Fred could you provide a English translation?
Hi,
I have a hard time understanding the Swedish Chef. My knowledge of the Swedish is nill and the Swedish Chef is hard to understand. Fred could you provide a English translation?
Re: Swedish Chef
Just don't fall into the trap of believing that we swedes
understand him either.
Elso Kwak said:Hi,
I have a hard time understanding the Swedish Chef. My knowledge of the Swedish is nill and the Swedish Chef is hard to understand. Fred could you provide a English translation?
Just don't fall into the trap of believing that we swedes
understand him either.
Re: Re: Re: Swedish Chef
So it's like most other long threads on this forum then. 🙂
Elso Kwak said:
So it's like most other long threads on this forum then. 🙂
I didn't know an acceptable legal phrase, m'lord.
Fred, did you have anything more about your last remark?
If you mean the last remark in the post you referenced, my rates for you are double what I charge everyone else.
"Since when isn't hard feedback a stability issue?"Feedback always is even for systems with closed loop AC gains of greater than one.
"at the expense of stability"
Speaking of expenses, by my caculations, you have run up 317 dollars and 82.5 cents worth of consulting in this thread alone.
Christer,
you're standing exactly where he was when he saw the snake---du står exakt på det ställe där han stod när han såg ormen
It seemed too good to pass up in my collection mangled Swedish I have posted here. It reminded me of the Hungarian phrasebook sketch.
I cannot wait 'til lunchtime,
Fred
Fred, did you have anything more about your last remark?
If you mean the last remark in the post you referenced, my rates for you are double what I charge everyone else.
"Since when isn't hard feedback a stability issue?"Feedback always is even for systems with closed loop AC gains of greater than one.
"at the expense of stability"
Speaking of expenses, by my caculations, you have run up 317 dollars and 82.5 cents worth of consulting in this thread alone.
Christer,
you're standing exactly where he was when he saw the snake---du står exakt på det ställe där han stod när han såg ormen
It seemed too good to pass up in my collection mangled Swedish I have posted here. It reminded me of the Hungarian phrasebook sketch.
I cannot wait 'til lunchtime,
Fred
Attachments
Re: I didn't know an acceptable legal phrase, m'lord.
Yes I understood the sentence, but not what you meant or what
was supposed to be funny. Is from some Monty Python sketch
I have missed?
Fred Dieckmann said:
Yes I understood the sentence, but not what you meant or what
was supposed to be funny. Is from some Monty Python sketch
I have missed?
Re: I didn't know an acceptable legal phrase, m'lord.
"My hovercraft is full of eels!"
Fred Dieckmann said:
"My hovercraft is full of eels!"
- Status
- Not open for further replies.