New answers tagged analog
3
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4 Hours Analog Timer with accuracy without Arduino
The solution has three basic components.
A crystal oscillator. The lower the frequency, the better; it reduces the number of divider ICs.
If you start with a 32 kHz watch crystal, then you need a ...
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4 Hours Analog Timer with accuracy without Arduino
For your desired ~100ppm accuracy you're better off with a crystal, eg. 32,768Hz tuning fork type.
You could do it with three ICs- a 4060 oscillator/divide by 16,384 which would give you 2Hz, a 4017 ...
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4 Hours Analog Timer with accuracy without Arduino
You can cascade the 4060 or its relative the 4040. I have done this last century and it is cheap and reliable. Downsides are PCB real estate and lack of flexability. I have seen the 4521 used but have ...
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What's the best/easiest way to measure an unkown inductance without an RLC meter?
It depends a lot on what the magnitude of the inductance is.
Within the accessible range a nanoVNA is cheap and easy.
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What's the best/easiest way to measure an unkown inductance without an RLC meter?
The inductance tester I found to work very accurately is similar to the other circuit in this question and is modeled in LTSpice. It is similar to the top rated circuit here except that circuit will ...
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Push-pull BJT configuration can't pull output to ground fully
You can't get below 0.7 with devices that way. Exchange the NPN and PNP; put 2 10k in series between the bases and drive the midpoint.
That'll get to about 0.1 V. For lower use mosfets - one CD4007 ...
- 19.8k
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Push-pull BJT configuration can't pull output to ground fully
Are you sure you want pull to Gnd instead of high impedance?
If the Gnd is true you can use a common emitter. When you use a Rc=1k and 100k to mixer the error should be less than 1%. At plus 3V the Rc ...
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LT3582-12 Not Putting Out +-12V (edit: downstream component is to blame)
The LT3582-12 is not at fault, the load is somehow overpowering the negative rail of the supply. Thanks to @Jens for the suggestion.
When the load was driven by an external power supply, the board ...
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Help on PID circuit design
Q: What is the point of D7,D8,Z1. When I add them to my LTSPICE simulation, the comparator does not work anymore (see below).
It's inconclusive that your simulation isn't working. From what I see, it ...
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Help on PID circuit design
The C7&C8 form an nonpolarised capacitor from polarised ones. It is because nonpolarised caps are few uF available only.
The D7&D8 form an AND gate, i.e. both comparators have to be high to ...
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Am I doing something wrong in making this gate bootstrapped switch?
Note that the paper says that given a minimum supply voltage of 0.95 V:
We assume a single-ended input range from 0.25 to 0.75 V, which translates to a least-significant-bit (LSB) size of 1 V / 1,024 ...
- 177k
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Analog PID - Integrator reset
Q1: Is this kind of design still relevant? I think there are PIDs everywhere but I find it hard to believe that there has to be someone switching a button frequently for their servoing to work?
This ...
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Analog PID - Integrator reset
PIDs are of course still used. Sometimes the circuit differs, but they all have similar elements. You are correct -- if the opamp saturates, then the 'I' portion becomes zero (so do all the other ...
- 19.8k
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Clipping the output of an Op-Amp using Zener diodes
One option might be to use a rail-to-rail opamp and limit the supply voltages to +/- 5 V. Some Schottky diodes can be used to limit the input voltage to within a couple hundred millivolts of the rails ...
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IC identification - Analog Devices with top marking S2 M
This is an Analog Devices ADG5401. It is a Single SPST switch. I was able to find this device by going onto Analog's website and using their search tools by typing in "S2M" and then ...
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Do you really need input bias current cancellation resistors?
How Rb create a high impedance node?
The non-inverting input is the node that they allude to.
In the TI schematics in your question, the "high impedance" node is only 7.5 kΩ but, it could ...
- 467k
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What is the best way to convert positive voltage to negative while consuming the smallest amount of power?
Where each rail takes either a similar current, or a low current, it's often better to split the battery voltage to provide a virtual ground somewhere between the rails.
This is not the case if the ...
- 171k
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How can I down mix stereo to mono audio on a DFPlayer Pro?
While the question asks for how to modify the circuit, as an alternative if you control which MP3 files are used by the player the MP3 files could be converted from stereo to mono before being copied ...
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How can I down mix stereo to mono audio on a DFPlayer Pro?
You need to sum left and right into mono before the amp and use only one channel of the amp. Use resistors like you suggested in your question to sum left and right together. It's the most cheapest ...
- 165k
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How does an AC signal in a Transistor Amplifier Circuit swing output voltage if it is going below 0.7V?
Yes, your analysis is correct. That particular amplifier can't handle a 2 Vpp input signal without "clipping". That's the name of the effect that occurs when the transistor is driven into ...
- 177k
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IRF540 MOSFET overheating when used with IRS2104 driver as class D amplifier
Get rid or significantly reduce the 2.5 μF capacitor. It will draw massive levels of near-instantaneous current on each switching cycle. A pi-filter is a bad idea under these circumstances.
It all ...
- 467k
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Positive and Negative Voltage Buffers with Current Buffers
It's not generally bad to reverse bias the base-emitter junction, and doing so doesn't automatically damage the transistor, unless that causes excessive power dissipation. There is apparently some \$\...
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Simulation of transimpedance amplifier direction of current source
I'll start by pointing out that those two circuits are identical with two exceptions:
The op-amps have different supply potentials, which dictates the maximum and minimum output potential.
The non-...
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Why does this high pass filter/rc differentiator behave like this?
If I'm correct, the circuit above is an RC differentiator/high pass filter
It is a high-pass filter. It's not an ideal differentiator.
CLK goes high, charges capacitor,
Yes, but it charges the ...
- 20.3k
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0-10V or 4-20mA conversion to 0-3.3V for Microcontroller ADC
This simple solution might work:
simulate this circuit – Schematic created using CircuitLab
Your error likely comes from your diode. Zeners are a poor choice in your circuit. D1 clamps the ...
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How to convert two floating voltages into two differential signals centered around a constant mode voltage without a fully differential opamp?
As @The Photon has already pointed out, a transformer (1/1:1) should be useful.
Adjust Vcm (V3) as needed.
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0-10V or 4-20mA conversion to 0-3.3V for Microcontroller ADC
In this design I've mapped the current-loop inputs to the analog input range 0.0 ... 3.0 V.
I chose 3.0 V as maximum to add some leeway in case I had to calibrate the inputs. The voltage followers ...
- 4,550
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Struggling to understand zero cross detecting circuit
Thanks to the answer of @Kevin White I understood it.
The originally shown schematic is IMHO very difficult to understand.
I added a schematic that should be easier understandable, because it shows ...
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Using IRS2104 gate driver to drive BJT push pull stage
VS - VB is limited to 25V absolute maximum, so HO will not go from 100V to 0 (at least not more than once).
HO also has the wrong phase to drive a PNP transistor.
Even if it did work (perhaps with ...
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Symmetric square wave duty cycle reduces with increase in frequency in push pull stage
Try this circuit. It can easily drive close to 100mA into the load with only small duty cycle degradation at shown pulse drive frequency of around 100kHz.
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Symmetric square wave duty cycle reduces with increase in frequency in push pull stage
The duty cycle changing is explained by the asymmetric first stage. It just is not visible at low frequencies.
You have strong fast transistor that pulls signal down hard and fast with large sinking ...
- 165k
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0-10V or 4-20mA conversion to 0-3.3V for Microcontroller ADC
We don't know anything about the ADC, so it's impossible to know what to do to protect it. All we can do is make sure it never sees a voltage outside the range 0V to +3.3V. That's easy to do with an ...
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0-10V or 4-20mA conversion to 0-3.3V for Microcontroller ADC
The 3.3V zener diodes are going to cause large errors near the high end of the inputs. Here is a simulation showing the nominal errors with one particular 3.3V Zener (not counting Zener tolerance, ...
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