# Sawtooth wave oscillator

• gsan
In summary, the conversation discusses designing a sawtooth wave oscillator using a circuit found online. The person is asking for help with obtaining the equation and understanding the circuit's functionality and limitations. It is suggested that the person should show their own work before receiving help.

#### gsan

Hi, I need to design a sawtooth wave oscillator, and I found this designe from http://hobby_elec.piclist.com/e_ckt17.htm [Broken]

does anyone can show me how to get the equation, f=(1/2C(R1+R2))x(R3/R4) and also the osillator is valid for what range of the frequency, thanks.

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Whether this is homework or not, you need to show some of your own work before we can provide some tutorial help.

What do you think the circuit is doing, and why? What would the logical components of a sawtooth generator be? Are they in that circuit diagram? How would you go about analyzing the circuit, to try to see if the equation listed is correct? What error terms would you think might also need to be accounted for, in addition to the equation? What limitations would there be on the circuit's operating frequency and un-trimmed accuracy?

I would first like to commend you on your efforts to design a sawtooth wave oscillator. It is a valuable skill to be able to design and build electronic circuits.

To answer your question, the equation f=(1/2C(R1+R2))x(R3/R4) is derived from the principles of RC circuits and feedback oscillation. In this particular circuit design, the frequency is determined by the values of the capacitors (C) and resistors (R1,R2,R3,R4). The equation is a result of the feedback loop created by the capacitors and resistors, which allows for the oscillation of the sawtooth wave.

As for the valid range of frequency, it will depend on the specific values of the components used in the circuit. However, the frequency range can be adjusted by changing the values of C, R1, R2, R3, and R4. It is important to note that the range of frequency will also be affected by external factors such as power supply voltage and temperature.

I would recommend doing some further research on RC circuits and feedback oscillation to better understand the principles behind this equation and how it applies to your circuit design. Additionally, you can experiment with different values of components to see how it affects the frequency range of your oscillator.

Best of luck with your design process!

## 1. What is a sawtooth wave oscillator?

A sawtooth wave oscillator is an electronic circuit that generates a waveform with a triangular shape. The waveform rises linearly and then drops suddenly, creating a sawtooth pattern.

## 2. How does a sawtooth wave oscillator work?

A sawtooth wave oscillator typically consists of a capacitor, a resistor, and a transistor or operational amplifier. The capacitor charges up until it reaches a threshold voltage, at which point it discharges rapidly, creating the sawtooth waveform.

## 3. What are the applications of a sawtooth wave oscillator?

Sawtooth wave oscillators are commonly used in electronic music synthesizers, as well as in analog-to-digital converters and time-base generators for oscilloscopes. They can also be used in voltage-controlled oscillators and frequency modulation circuits.

## 4. What is the difference between a sawtooth wave oscillator and a triangle wave oscillator?

While both sawtooth and triangle wave oscillators produce waveforms with a triangular shape, the main difference is in how the waveform is created. A sawtooth wave oscillator charges and discharges quickly, creating a sharper rise and fall, whereas a triangle wave oscillator charges and discharges more slowly, resulting in a smoother waveform.

## 5. Can a sawtooth wave oscillator be used for frequency modulation?

Yes, a sawtooth wave oscillator can be used for frequency modulation by varying the frequency of the oscillator using a control voltage. This results in a change in the frequency of the waveform being produced, creating a unique sound in electronic music applications.