Optimizing Sawtooth Wave Generator: Understanding Voltage and Amplitude

  • Thread starter Thread starter Bassalisk
  • Start date Start date
  • Tags Tags
    Generator Wave
AI Thread Summary
In a sawtooth wave generator circuit, with Vcc at 15V, a voltage drop across Re of 2.7V, and a saturation point of Uce at 0.2V, the maximum voltage across the capacitor can be calculated as 12.1V. The transistor will enter saturation when the capacitor is full, but the circuit typically operates by discharging the capacitor before it reaches maximum amplitude. Adjusting the frequency of the impulses can influence the amplitude, but this is not the standard use of the circuit. Instead, the charging rate of the capacitor should be modified by adjusting R1 to achieve a desired frequency. This understanding confirms the correct approach to optimizing the sawtooth wave generator's performance.
Bassalisk
Messages
946
Reaction score
2
http://pokit.org/get/f118bc654187e429ec1bb489e1eb3a38.jpg

Suppose we have a sawtooth wave generator, like in the picture.

I have a fairly simple question:

If let's say Vcc is 15V, and let's say voltage drop across Re is 2.7V, and saturation point of Uce is 0,2 V. Provided that the period between impulses are long enough, what will happen when capacitor is full? Transistor will go into saturation right?

Or another way to put it, will my MAXIMUM(allowed) amplitude, or voltage across the capacitor be:

15-2.7-0.2=12.1 V?

And I can choose my amplitude by adjusting the frequency of those impulses?
 
Last edited by a moderator:
Engineering news on Phys.org
Yes, that is right.

That is not how this circuit would normally be used, though.

Ideally, the lower transistor's base would get a new pulse to discharge the capacitor just before the sawtooth wave reached maximum amplitude.

If you wanted to use a different frequency, then you would adjust R1 to give a different charging rate for the capacitor.
 
vk6kro said:
Yes, that is right.

That is not how this circuit would normally be used, though.

Ideally, the lower transistor's base would get a new pulse to discharge the capacitor just before the sawtooth wave reached maximum amplitude.

If you wanted to use a different frequency, then you would adjust R1 to give a different charging rate for the capacitor.

Understood. Thank you. Needed somebody to confirm my thoughts.
 
While I was rolling out a shielded cable, a though came to my mind - what happens to the current flow in the cable if there came a short between the wire and the shield in both ends of the cable? For simplicity, lets assume a 1-wire copper wire wrapped in an aluminum shield. The wire and the shield has the same cross section area. There are insulating material between them, and in both ends there is a short between them. My first thought, the total resistance of the cable would be reduced...
Hi all I have some confusion about piezoelectrical sensors combination. If i have three acoustic piezoelectrical sensors (with same receive sensitivity in dB ref V/1uPa) placed at specific distance, these sensors receive acoustic signal from a sound source placed at far field distance (Plane Wave) and from broadside. I receive output of these sensors through individual preamplifiers, add them through hardware like summer circuit adder or in software after digitization and in this way got an...
I am not an electrical engineering student, but a lowly apprentice electrician. I learn both on the job and also take classes for my apprenticeship. I recently wired my first transformer and I understand that the neutral and ground are bonded together in the transformer or in the service. What I don't understand is, if the neutral is a current carrying conductor, which is then bonded to the ground conductor, why does current only flow back to its source and not on the ground path...
Back
Top