Hi,
Thanks Dana again for the simulation.
The datasheet says LT1028 is stable with inverting circuit and A = -1.
So your inverting setups show ringing. Quite expectable.
But I was surprised by your first non inverting setup showing very stable condition on A = +1, while the datasheet says it is not stable.
Now the second setup with feedback resistor meets more my expectations. Lots of ringing, at the edge to oscillate.
Thanks again.
On the other hand the LT1028 is a very low noise OPAMP. It has an input noise less than a 50 Ohms resistor. So noise wise it makes no sense to use input impedances higher than those 50 Ohms.
An often with that low noise ... one needs an amplifier with high gain. So with high gain and low input impedance the LT1028 works great. I uset it this way in some high end audio circuits decades ago.
*******
So the conclusion to this thread is, that the LT1028 is not the best choice for this application. The application does not need that extremely low noise but it needs stability. I still vote for local feedback combined with the use of a unity gain stable OPAMP. But indeed I still don´t understand what the OP really wants to achive. The requirements regarding timing, the freqency range ... the true goals.
Klaus
Hello Klaus ,I am Tuning a YIG FM coil with this device.
The frequency range of the YIG is about 12MHz at 9.5Ghz center frequency.
Tony said that i was wrong when thinking that my analog driver needs 0 bandwidth( DC input only)
I dont understand how the BW of the driver has anything to do with the YIG FM coil?
The FM coil data:
sensitivity: 450 KHz/mA
3dB bandwidth 2.2MHz
resistance 2Ohm
inductance 1.5uH
How this data influences of the requirements i need to implement on the driver?
Thanks.
Hello Tony, you are correct that i am very over my head with this,thank you for the help.
I can try and start over with a new PCB.i will try to design a high gain high bandwidth.
In a previos post you used AD8033 instead of the LT1028 data sheets shown in the link below.
COuld you please help me understand what did you see in the data sheet that made yu understand that AD8033 is more suitable?
Thanks.
Not quite sure what you want to say here. Obviously the "minimum magnetic field" is provided by the main tuning coil, not the FM coil.This makes no sense for a YIG oscillator that needs a minimum magnetic field to oscillate and then can span many GHz.
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?