Hi all
I got the following example from a book
Example 3.10
Design the op-amp Pierce oscillator in Figure (attached) to oscillate at 10 kHz.
Ans:
The op amp used is a general-purpose op amp, such as the 1458 or 741. General-purpose op amps have typical slew rates of 0.5 V/ s and gain-bandwidth products(fT ) of 1 MHz. These parameters limit the frequency of oscillation. Of course,there are many special purpose op amps with high slew-rate values and high fT values, which can be used to attain higher frequency of oscillation.
Using supply voltage values of V+=5V and V −=−5V, the op amp output islimited to its saturation values (i.e., approximately±5V). In this case the
SR limitsthe frequency of oscillation to:
fo = SR/2*pi*Vo = (0.5*10^6) / 2*pi*5 = 15.9 kHz
MY QUESTION : I am designing a colpitt oscillator with LF351N which has the following features,
1) Slew rate = 16V/us
2) Gain Bandwidth product = f=100kHz
3) Using 9V DC supply
So going by above equation my frequency of oscillation
fo = 16*10^6/ 2*pi*9 = 282942.12 Hz =0.2 Mhz
Am I correct? Im just lost as to what to do next and even with this set !
How do I get started in building a colpitts oscillator?
Kindly help
I got the following example from a book
Example 3.10
Design the op-amp Pierce oscillator in Figure (attached) to oscillate at 10 kHz.
Ans:
The op amp used is a general-purpose op amp, such as the 1458 or 741. General-purpose op amps have typical slew rates of 0.5 V/ s and gain-bandwidth products(fT ) of 1 MHz. These parameters limit the frequency of oscillation. Of course,there are many special purpose op amps with high slew-rate values and high fT values, which can be used to attain higher frequency of oscillation.
Using supply voltage values of V+=5V and V −=−5V, the op amp output islimited to its saturation values (i.e., approximately±5V). In this case the
SR limitsthe frequency of oscillation to:
fo = SR/2*pi*Vo = (0.5*10^6) / 2*pi*5 = 15.9 kHz
MY QUESTION : I am designing a colpitt oscillator with LF351N which has the following features,
1) Slew rate = 16V/us
2) Gain Bandwidth product = f=100kHz
3) Using 9V DC supply
So going by above equation my frequency of oscillation
fo = 16*10^6/ 2*pi*9 = 282942.12 Hz =0.2 Mhz
Am I correct? Im just lost as to what to do next and even with this set !
How do I get started in building a colpitts oscillator?
Kindly help
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