A device or circuit that generates an AC signal at a certain frequency.
0
votes
1answer
308 views
No LSE connection to STM32. Is it OK?
I'm developing board which have STM32F103VET6. I don't need RTC so is it OK to not connect the OSE32_* pins to external oscillator? Will there be any side-effects? All the reference design I found all ...
9
votes
4answers
460 views
Low power, low voltage, slow (0.1Hz) oscillator?
I had the opportunity to analyze a very interesting circuit today using a programmable unijunction transistor as a timer.
The power supply varies, and the circuit must operate on under 10uA of ...
1
vote
3answers
640 views
How to get a PIC12F1822 running at 32MHz
I just can't get my PIC12F1822 to switch to 32MHz (8MHz + 4xPLL)
I am telling OSCCON to switch to 8MHz, but, according to the debugger, that value is never loaded into it! I also wait for the High ...
0
votes
1answer
490 views
Choicing crystal or external oscillator for time critical project on PIC18F
Need to learn how making frequency counter (or any time critical project) using PIC18F that display output over USB.
Having choice of 3 clock sources:
±50ppm 4.0000 MHZ crystal ATP040SM
4.0000 MHZ ...
3
votes
7answers
1k views
Using microcontroller as oscillator for high voltage power suppy?
MightyOhm has designed a geiger counter which is here. I am not very clear but I think he is using the 555 timer as an oscillator in the high voltage power supply section. I've attached his schematic ...
2
votes
1answer
340 views
Seeing sine wave output from external oscillator but expect to seeing square wave output
Buy some external oscillator from eBay and hook up to 5V DC and RF output to DSO.
Seeing sine wave output from external oscillator but expect square wave output.
I connect lab PSU to ...
0
votes
1answer
1k views
Sine wave frequency vs. PWM frequency (AVR)
I'm using an AVR Mega 168 to generate a sine wave via pulse width modulation. My goal is to generate a sine wave with a frequency of approximately 50Hz. I understand that the PWM frequency needs to be ...
5
votes
4answers
365 views
What causes oscillators to sync up with each other?
Messing around with simple Theremin circuits, the variable oscillator would get "stuck" in sync with the reference oscillator, and not move until disturbed significantly (like "snap to grid" in a ...
3
votes
1answer
148 views
Binary Counter and an Oscillator for frequency generation
I'm interested in creating low frequencies using a high-frequency oscillator. For example - using a 12Mhz oscillator to create 1Khz, 2Khz waves.
I've been said that using a Binary adder(oops) counter ...
1
vote
2answers
262 views
Sine Oscillator - for audio frequency
I'm looking to create several sine waves on a single circuit. All must be under 20Khz frequency and each must be unique. Mostly it will be 5-10 frequencies needed.
As I found - almost all crystal ...
4
votes
5answers
1k views
What is the simplest way to make an oscillating signal?
Imagine you have a black box with 5VDC and ground inputs and you have to create one output that is an oscillating signal. What is the simplest circuit that can do so? Can you create a tank circuit ...
3
votes
5answers
1k views
Is this a suitable sine wave osc? how would I control the frequency?
Overview-
I'm making a bank of analog sine wave oscillators and I'm interested in keeping the design compact.
I've started by making a Wien Bridge oscillator. As I'm working from a single power ...
3
votes
2answers
284 views
Are there any commercially available crystals in the sub 32 kHz range?
I'm looking for a low power clocking solution and it looks like crystals bottom out at 32 kHz. Are there any low power (nA) solutions (crystals/ceramic resonators/custom transistor oscillator ...
2
votes
2answers
1k views
What is the ppm in the crystal oscillator?
I'm a student, and I'm working on a low power communication project, I am trying to design a PCB using the TI CC2540 sample design. There is a MC-306(32.768kHz, 12.5pf, and 20/50ppm)
I don't know what ...
1
vote
4answers
3k views
Use PIC internal oscillator
I'm using a PIC16F1824 with an external 4MHz oscillator. I actually want to use the internal oscillator, but the timing seems incorrect.
For example, I tried to use delay_ms(1000), and it delayed 5 ...
4
votes
4answers
2k views
Internal or external oscillator
I always use the internal oscillator that pics have as I have never found the need to run anything at higher frequency than 8 MHz (which is the fastest the pics I use tend to be able to go). Are there ...
4
votes
1answer
4k views
How to design the capacitors used with Crystal Oscillators?
I have seen circuits involving crystal oscillators connecting two capacitors between each of the crystal legs and ground. I would like to know how to design the value of these capacitors for different ...
3
votes
3answers
1k views
Crystal oscilator not oscilating on a PIC
I am experimenting with a PIC16F84A at the moment.
I can get this working fine using an RC network for the clock.
When I switch to using a crystal (the usual xtal across pins 15&16 with 2 caps ...
1
vote
1answer
379 views
8051 SMARTCARD DESIGN
I'm trying to design a smart card interface using one 8051 UART and a Pierce oscillator circuit.
The project seems to be working, because I'm getting response from the smart card. However, I'm having ...
3
votes
1answer
666 views
Negative Charge Pump with Ring Oscillator
I was told it was possible to get a negative voltage from a ring oscillator (that doesnt go negative), I was wondering how is that possible?
Thank you in advance.
4
votes
1answer
141 views
Does a clock oscillator require a load?
I want to use this clock oscillator
http://www.ecsxtal.com/store/pdf/ecs-2100x.pdf
It does not require loading capacitance.
However, it says "3.3V operation (optional)", yet on the same page it ...
1
vote
2answers
448 views
Internal oscilator vs external and Serial port question
I've been thinking about getting into using some pic microcontrollers, and I found the below two things to help get me started. But, on the product page for the microcontroller, it says 20 mhz, but ...
2
votes
1answer
536 views
Cheap simple way to make an adjustable 1-10 MHz square or sine wave oscillator
For a test of a filter and video transmitter gear, I need a variable frequency (potentiometer adjusted) sine or square wave oscillator, adjustable from about 1 to 10 MHz. Output about 1Vp-p okay, but ...
1
vote
2answers
524 views
Need oscillating servo/stepper motor guidance
EDIT: Additional Information below original post...
Looking for a 360 degree servo motor that has adjustable control for timing of steps
(or at the least timing per full oscillation) and can support ...
0
votes
2answers
253 views
Pierce Oscillator issues
I am having a problem in trying to build pierce oscillator to work with my SMART Card reader design. I am using 3.58MHz oscillator, 74HCU04 gate IC for the NOT gate, and the 22pf capacitor and 1M ...
3
votes
3answers
515 views
Novice question about low-pass filter
I am trying to construct a simple low-pass filter for the following scenario: A high-voltage DC signal with lots of noise. I looked at Wikipedia's article on a simple passive low-pass filter. I ...
3
votes
4answers
462 views
Why is this oscillator unstable?
I designed a simple triangle wave oscillator based around a switchable curent soure. It works for a few cycles, then it becomes unstable and finally stops working altogether. Why is this?
If anyone ...
0
votes
2answers
634 views
Why is a capacitor placed in parallel with oscillator output?
I have a circuit board with an oscillator and I'm curious about why there is a capacitor hooked up to the output. The oscillator is a SWO series HCMOS Square Wave output crystal oscillator. The ...
1
vote
2answers
624 views
How to avoid ±voltage on capacitors in astable multivibrator
I've been experimenting with oscillators, and am particularly fond of a very low-current MOSFET design that uses ceramic capacitors and oscillates at about 1 to 10 Hz. However, I am having trouble ...
1
vote
1answer
350 views
create oscillator with variable frequency by computer
How can I use my computer to control the frequency of a variable oscillator?
THANK YOU.
2
votes
2answers
397 views
Explain this circuit?
This is one of the circuits in the Electronics 9/10 class.
The package did not explain how transistor combination worked and why the capacitor will reverse its current.
Can you explain this ...
18
votes
4answers
2k views
Why does a faster clock require more power?
If you overclock a microcontroller, it gets hot.
If you overclock a microcontroller, it needs more voltage.
In some abstract way it makes sense: it is doing more computation, so it needs more energy ...
5
votes
4answers
906 views
Push Pull Oscillator
Does anyone know how to build a push/pull oscillator or a similar square wave oscillator?
5
votes
1answer
301 views
How can I invert a solar-powered oscillator's frequency?
I have a hobby project that's been on the backburner for about 3 years now. It's very simple - just a solar-powered oscillator hooked up to a speaker, that changes frequency in response to the level ...
6
votes
3answers
238 views
Grokking oscillators
Can someone explain to me / point me to a good explanation of the theory behind an electronic oscillator? The Wikipedia entry explains what, but not how, which is what I need to know.
TIA.
8
votes
8answers
3k views
What's the easiest/cheapest variable-frequency sine wave oscillator?
A Google search will give you a few billion ideas. Which is the simplest/easiest/cheapest that you know of?
Generating a square wave and then filtering out the harmonics isn't a good solution unless ...
