Hi all
I got the following example from a book
Example 3.10
Design the opamp Pierce oscillator in Figure (attached) to oscillate at 10 kHz.
Ans:
The op amp used is a generalpurpose op amp, such as the 1458 or 741. Generalpurpose op amps have typical slew rates of 0.5 V/ s and gainbandwidth products(fT ) of 1 MHz. These parameters limit the frequency of oscillation. Of course,there are many special purpose op amps with high slewrate 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 opamp Pierce oscillator in Figure (attached) to oscillate at 10 kHz.
Ans:
The op amp used is a generalpurpose op amp, such as the 1458 or 741. Generalpurpose op amps have typical slew rates of 0.5 V/ s and gainbandwidth products(fT ) of 1 MHz. These parameters limit the frequency of oscillation. Of course,there are many special purpose op amps with high slewrate 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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