New answers tagged oscillator
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BJT ring oscillator
If you want a square wave and you need an inverted output, use a hex(6) Schmitt inverter IC with resistor from input to output and a capacitor from input to ground..
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BJT ring oscillator
Just to point out the use of a Schmitt (one that in this case uses 3 BJTs, too, but it is only one Schmitt stage), here's an example that I literally threw together from memory and some guessing from ...
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BJT ring oscillator
When is an inverter NOT an inverter? (Pun intended.)
Understand that digital is a subset of analog. Digital logic is a collection of rules, which, when a system obeys them, can be used to synthesize ...
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Astable Multivibrator Not Oscillating
The base connections aren't crossed. You need to swap one end of the white and blue wires.
As Antonio said, the base resistors should be much larger than the collector resistor. I would use 22k and ...
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Astable Multivibrator Not Oscillating
Base resistors should be at least 10/20 times collector resistors.
These collector resistors should not be too low -> 1 kOhm.
Then the base resistors should be something like 10 kOhm or 20 kOhm.
NB:...
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Crystal distorted wave
The load capacitance of your crystal specifies 18 pF but your circuit is probably more like 12 pF if you're using 18 pF capacitors. To achieve 18 pF load capacitance, you have to use ~30 pF capacitors....
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How to generate a clock signal using an op-amp
When operated on a single supply, with its negative rail tied to GND, a 741 output stage cannot produce a TTL low signal level. IOW, the output cannot swing all the way down to +0.8 V (or less) above ...
- 18k
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How to generate a sine wave that is in phase with a generated square wave at 1MHz for lock-in amplifier?
I know that we can use a schmitt trigger for a sine wave to sqaure wave
... and the problem with that is?
This is the simplest and best solution to your requirement. Low component count, precise ...
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How to generate a sine wave that is in phase with a generated square wave at 1MHz for lock-in amplifier?
Just generate a sinewave as your reference signal and derive the squarewave from that. As you've already mentioned, this is easily done with a comparator / Schmitt trigger.
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Why not put a crystal oscillator inside the microcontroller?
One issue with adding a crystal to a microcontroller is thermal considerations. The frequency of crystal oscillators varies with temperature, and they are typically tuned to be their designed ...
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Why not put a crystal oscillator inside the microcontroller?
In conclusion to the above answers ... (and because noone explicitly mentiones it):
Cost would go up, size of target market would shrink.
Why do something which increases design and production costs ...
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How can I attenuate noise from synchronous divider and OCXO?
You are taking your output from pin 4 of the last 4017. This is a 10% duty cycle waveform, so you would expect a large amount of 2nd harmonic. In fact all harmonics would be present in large amounts ...
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Measuring Vackar Oscillator Output Amplitude and High Frequency Effects
The FET gate is a diode. Normally it is kept reverse biased or at least below the 0.5 - 0.6 volt positive bias with respect to the source where it would start to conduct. Obviously it will start ...
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Why not put a crystal oscillator inside the microcontroller?
Mostly because no one else does, why make an obscure non-standard product which can't be easily replaced.
Yes you could glue a crystal in top of MCU (or mold it inside the plastic package). It will ...
- 136k
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Power supply coupling of inductive resonant sensors
Power supply filtering is about all you need for most problems like this. A capacitor across the supply for each sensor may be enough, or you may need to add a ferrite bead in series with the supply. ...
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Why not put a crystal oscillator inside the microcontroller?
Here's a crystal oscillator (source):
In order to work, a crystal must be suspended in free air (or inert gas) by the edges. It works like a tuning fork, it is a mechanical resonator with electrical ...
- 71.9k
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Why not put a crystal oscillator inside the microcontroller?
Total system cost would be higher than with an external crystal.
The IC supplier would have to source the crystal from another supplier most likely, one who could guarantee supply over the life of ...
- 383k
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Why not put a crystal oscillator inside the microcontroller?
CC2652RB is an example of a SimpleLink™ Crystal-less BAW Multiprotocol 2.4 GHz Wireless MCU.
The datasheet contains:
The SimpleLink™ CC2652RB device is the industry’s first multiprotocol 2.4 GHz ...
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Why not put a crystal oscillator inside the microcontroller?
A crystal is very different in physical construction from an MCU, and most crystals are annoyingly large to integrate into a chip package. It's possible, however, to integrate other types of (smaller) ...
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Why not put a crystal oscillator inside the microcontroller?
A crystal is fabricated on a completely different process and from a completely different material than a microcontroller is. You can't integrate them both into a single chip, so you would have to ...
- 29.9k
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Why not put a crystal oscillator inside the microcontroller?
The main reason is that MCUs and crystals use very different production processes. One is silicon etching in a photochemical process and the other is a mechanical machining one. Often you can't even ...
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Unable to get my astable multi-vibrator working in LTspice
Here is one problem: The output of the op-amp is connected to GND.
There may be other problems.
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Why is my crystal oscillator (4 pin DIP 4 MHz unbranded from ebay) producing unusable clock signal waves?
The oscilliscope you linked to has a 200 KHz bandwith - it will not show anything near the correct waveform and voltages of a 4 MHz signal.
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Can negative feedback in an opamp circuit be applied to the noninverting terminal?
Yes, sometimes you require feedback to be applied to the non-inverting input of the error amplifier, as I discussed here.
In the classic amplifier setup, feedback from the overall output is applied to ...
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Can negative feedback in an opamp circuit be applied to the noninverting terminal?
What is virtual short?
... can I apply virtual short to solve it?
It is a big challenge to uncover what lies behind verbal clichés that have been used mechanically for many years... so much so that ...
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How does this Pierce oscillator work?
RFChoke and 2n2 LC decoupling network to avoid spurious oscillations
Crystal as per its current capacity will not be overloaded
Transistor should be upto vhf range
be supply can be fed by low cost ...
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I am repairing an automotive board. I want to know about the manufacturer of a crystal oscillator
The manufacturer is Hosonic Elec. They seem use similar markings for different crystals, so it's impossible to tell the exact model without additional information, like the size. Here are the markings ...
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Can negative feedback in an opamp circuit be applied to the noninverting terminal?
Further analysis show that the input nodes of OA1 can be swapped without changing the closed loop gain, which will be also -1.
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How does this oscillator circuit work? Inductor phase
Here is my short explanation:
The transistor has a finite (dynamic) output resistance r_out which - together with L2, L1 and C4 - forms a third-order highpass in ladder topology: r_out-L2-C4-L1 (...
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How does this oscillator circuit work? Inductor phase
How does this oscillator circuit work?
You should study Hartley and Colpitts oscillators: -
Image taken from Wikipedia - Hartley oscillator
Your circuit is a Hartley oscillator and a slightly ...
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