New answers tagged circuit-design
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Which signal should be fed into the single ended input of the PAM8320?
Should work.
Should work. That's approximately what the DY module does onboard already for the mono speaker output.
Do not connect class D speaker level output to amplifier input.
That's two ...
- 130k
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How I can use light to control of amplifier?
Well, I'd use two different photo-detectors (can be LDR, phototransistor/photodiode or even a module) side-by-side, place optical filters - red in front of one of them and green for another.
When ...
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How I can use light to control of amplifier?
Hopefully you are talking about a miniature size toy. If it was full size truck and you had the money and tools to build it you could be stamped to be a too dangerous person to be let stay free.
...
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Help Building CRT Driver That Takes Composite Video Input
The inductance of a deflection coil is substantial. It has to be taken into the account at least in horizontal deflection, when something as fast as drawing a TV picture is done. In televisions and ...
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Which is the default state of MCU's GPIO before initialization?
Figure 8.5 on page 62 of your data sheet shows 'GPIO pins as inputs with pullups disabled' after power up when \$\overline{XRS}\$ (the active low system reset) is asserted, before the user code starts ...
- 159k
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Which is the default state of MCU's GPIO before initialization?
All registers in all microcontrollers have a default value out of reset. This is described in the specific register documentation. You cannot possibly miss it if you ever read any MCU manual about any ...
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Which is the default state of MCU's GPIO before initialization?
You don't say which microcontroller you use, but there must be a section in the datasheet that explains how GPIO pins work and what are the defaults, not all pins are equal as some may be used for e.g....
- 130k
2
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Which is the default state of MCU's GPIO before initialization?
How can I find this in the MCU's datasheet?
You could try Ctrl + F for 'initial state' or 'startup state' and similar terms.
I think it is usual for pins to come up tristated or as inputs, i.e. ...
- 18.9k
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VESC and wireless receiver setup
connect rc controllers to the ppm port
Rx throttle to ppm port
then follow the vesctool wizard to map it
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Passive linear circuit to generate high-voltage spikes from a 10 V peak-to-peak square wave
The specifications do not mention an output impedance. Nor do they mention whether the spikes need to be unipolar, or whether they can have one polarity on the rising edge of the input, and the ...
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What is the significance of this circuit?
Have a look at this application note which explains how this circuit acts as a bi-direction level shifter.
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Can you draw power from the ADUM4160 USB isolator
If not, Is there an AIO component to isolate data+power?
There are a few such as the ADuM5400: -
It has a 500 mW power converter. The output can be used to power ADCs and some other analogue ...
- 437k
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Can you draw power from the ADUM4160 USB isolator
No. the ADUM4160 only isolates. It does not supply VBUS. You need to supply either VBUSx or VDDx on both sides.
Assuming you want to build a host with an isolated USB port, you can use just about any ...
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Designing around multiple voltage sources for a device powered by an external supply and connected to a PC via USB (Arduino Nano)
Disconnect the Vin pin completely if you plan to always power the Arduino from USB.
Or add a diode from +12 V to Vin, if you want to be able to also power from 12 V.
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-VOUT, and COM pins for DC-DC Converter
For devices like these, if there are multiple terminals with the same name, it is very likely that they are connected electrically somewhere inside the device. The multiple input and output terminals ...
- 15k
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Designing a differential equation circuit with op-amps
As example, here is a Van der Pol oscillator.
- 11.3k
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Build two independent circuits with one switch
Here's how, with the switch 'S1' being used to control the 12 V load and a 12 V electromagnetic relay to control the 5 V load.
- 16.1k
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Measuring voltage on an edison outlet in a hybrid vehicle
This arrangement is fairly common in small inverters and inverter-style generators (such as my Honda EU2000i). It allows the inverter to produce 120 V AC between the Line and Neutral wires without ...
- 57.4k
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How to turn an LED on in an inverter circuit
This high side switch using a PNP transistor acts like an "inverter circuit".
Vin = 0V -> LED is ON
Vin = 5V -> LED is OFF
Adjust R3 to limit the current you want in the diode. ...
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Voltage gain of this OPA circuit with AC input
The two input R1's are equal in value. Therefore:
For a true differential amplifier that delivers common mode voltage rejection or attenuation, along with a clearly defined gain equation, the orange ...
- 17.1k
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Voltage gain of this OPA circuit with AC input
This is a differential amplifier. Google "op amp differential amplifier" and you'll find billions of resources.
NOTE: One thing my eyes caught is that the ...
- 27.5k
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Questions about a CTAT circuit
If you consider base current as being negligible, VOUT * R6/(R5+R6) = VQ2B. So, if VQ2B is ZTAT, VOUT will be ZTAT because the resistor ratio is a constant. VQ1C = VQ2C but both are not ZTAT. They ...
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Simple circuit question: nodal analysis
Well, notice that using KCL we can see that:
$$0=\text{I}_1+\text{I}_2\tag1$$
And we also know that:
$$\text{I}_1=\frac{\displaystyle\text{V}_1-\text{V}_\text{o}}{\displaystyle\text{R}}\space\wedge\...
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Help finding a circuit for discharging a high voltage capacitor
Use an N channel depletion MOSFET: I don't know how to implement it as I will need a negative Vgs to turn it OFF.
I have previously used a normally-on transistor switch in a 1300 V impulse generator ...
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Latching comparator always starts at latching position
The solution was as simple as adding C1, Now on power-ups non-inverting input sees a higher voltage for a short moment and that prevents the comparator to go to latching state.
simulate this circuit &...
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Latching comparator always starts at latching position
You could label SW1 as "ON/RESET". This may be even desirable.
There may be a transient on the load - say capacitors charging up. In that case the latching is by design, even if undesirable....
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Latching comparator always starts at latching position
Two things can cause this:
Power-on surge. The load resistance is very low when cool but increases while heating up. Tungsen filament lamps or capacitance in parallel with the load are examples. If ...
- 12.9k
2
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Accepted
Improving voltage follower circuit for high voltage pulse
The turn-on/off time of the sold state relay (SSR) is the cause of the lower than expected output voltage.
Switching to a faster SSR (AC30 as mentioned in a comment) fixed the issue and now the pulse ...
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Help finding a circuit for discharging a high voltage capacitor
I don't see the problem with using a "normally off" device like an enhancement-mode NMOS transistor. You just need to bias the gate from the capacitor, and short it out when you want the ...
- 169k
5
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Help finding a circuit for discharging a high voltage capacitor
For a passively on or default on circuit requirement, this is how I would do it:
simulate this circuit – Schematic created using CircuitLab
As you state, you need negative voltage to turn off a ...
- 13.4k
15
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Help finding a circuit for discharging a high voltage capacitor
Forgive me for addressing the problem instead of your intended solution.
A 4.7 kOhm power resistor draws negligible power compared to the motor driver (70 W vs ~ 20 kW peak), and does so only when the ...
- 17.5k
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How to find resistors from E series for a certain ratio?
Here's my go-to Mathematica tabulator for this:
...
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Read multiple PT100 sensors with MAX31865
The "simplest" solution is to use 4 MAX31865 modules (available at not much more than the cost of the bare chip, but which include connectors and all the support components). Most terminate ...
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How to find resistors from E series for a certain ratio?
No Visual Basic, just equations. Here's my solution (scroll right for example):
TABLE 1 (CALCULATOR, horizontal)
Named cell
Equation in code style, other in italics
Value (Example)
Input
Data Input
...
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Safety of dual male / single female Y cords
Those Y-cords are used to get 240 volts from two 120 volt outlets. Some of the other answers and comments just say "to get more power than a single outlet would supply" without making this ...
- 57.4k
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Safety of dual male / single female Y cords
I know cables like this are sometimes used to connect loads (such as welders) which exceed the rating of a single socket. However, what you have is not code compliant, or legal for sale in most ...
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What is wrong with this circuit?
1.There is no power net available
2.MCU cant able to drive the Coil ,Coil required more current but MCU GPIO usually have 20 mA at Max
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What is wrong with this circuit?
It appears that you are referring to powering up the ECU when the ignition switch is turned on.
Here's the correct schematic.
However, a 'power hold' relay would also be required to keep the ECU ...
- 16.1k
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What is wrong with this circuit?
This is more of a typical relay circuit driven by a controller:
simulate this circuit – Schematic created using CircuitLab
A controller (or ECU) output port pin (P1), is usually not strong ...
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5
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What is wrong with this circuit?
a) There is no power to the coil (and there should be). All I see is a resistor labeled "ECU", but an ECU and a resistor are not the same thing.
b) There is power across the contacts (and ...
- 17.5k
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Can FT232HL VCCIO be powered from external source?
Got a definite answer from FTDI support:
Unfortunately this use case is not viable.
See section 6 FT232H Configurations of the FT232H Datasheet.
The design can only be USB bus powered of self-powered ...
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Can FT232HL VCCIO be powered from external source?
Yes it can, The VCCIO just defined the logic levels of the outputs. You the FT232h has an internal regulator with two outputs, a 3.3V or 1.8V you could use either of those for VCCIO. Or you could use ...
- 76.3k
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Accepted
Can FT232HL VCCIO be powered from external source?
In short, yes, you can fully power the FTDI chip with only 3.3V from the MCU to build a self-powered USB device as depicted in datasheet Figure 6.3.
You can use external supply for VCCIO, but then it ...
- 130k
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Design non-inverting op-amp, with gain = 30estimate Ri, Rf and Rs from the standard 5% resistor value that will meet |AVCL| = 30 within +/-5%tolerance
You need to know Rth and Cmic to size the Rs so that you are within your tolerance and frequency limits.
However, there may be other reasons than Rth and Cmic that also limit the values of Rs, and it'...
- 130k
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How to connect a mini camera to four 3.5-5 inch TFT/LCD screens?
A camera with composite video output, and the TFT displays accepting composite video should do the trick. Those are fairly ubiquitous.
If you'd want to go the HDMI route, then the HDMI signal from the ...
2
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Accepted
How to setup a current controlled current source (CCCS) in the electronics workbench tool
I can't tell you how Multisim Electronics Workbench works. But in general, the current controlled current source in Spice uses this format:
...
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How to setup a current controlled current source (CCCS) in the electronics workbench tool
The CCCS needs to be controlled by the current flowing through the 2kOhm resistor so the workbench circuit is incorrect. the CCCS inputs must be placed in series with the 2kOhm resistor using some ...
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What are the theoretical constraints that prevent making the propagation delay of a CMOS inverter arbitrarily small?
Intuitively, one can think of having a large W/L ratio (which is the only parameter you can modify as a designer) to increase the drive strength of the inverter. In that way, the CMOS inverter will be ...
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What are the theoretical constraints that prevent making the propagation delay of a CMOS inverter arbitrarily small?
Making the channel width smaller doesn't increase the capacitance--it does, in fact, decrease it. However, it does increase the effect of the next stage's capacitance--a narrower channel means less ...
- 27.7k
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BJT voltage rail
In electronics we use conventional current flow, current flows from positive to negative. If you try to learn it using electron flow you're going to be swimming against the current (pun intended) as ...
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