Questions tagged [negative]
The negative tag has no usage guidance.
130
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Which side is the capacitor negative on this board? (IO/10 marking)
I removed a capacitor (C1 (400v/15uf) - highlighted in the picture) from this board to test on another board and now I want to put it back but I can't figure out the polarity. The traditional symbol ...
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Protecting a Schottky diode against negative spikes greater than its specified V_rrm
It appears this can be made to work, but I am not sure how. Related:
Protection against transient voltage spikes regarding ISO7637-1/2: TVS diode with Schottky diode suitable?
or a 40V schottky plus ...
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Regulating negative voltage with a positive LDO
I have Traco TEN 5-1221 to generate positive and negative 5 volts. I need to further lower the voltage to 1.5V. I decided to use a BA15JC5T for positive 1.5 volts.
Is there a way to use it for ...
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Voltage of electric motor
What is the range(min value and max value of average motor) of a voltage in an permanent magnet synchronous electric motor?
I am current working on a dataset of Permenant Magnet Synchronous Motor(...
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530
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Van conversion hookup point AC Earth to chassis negative
I'm helping my brother convert his van into a camper and installing solar panels, a leasure battery, and hook-up point, but I'm slightly confused. I've been working on the hook-up and loads of things ...
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LMV431 to generate negative voltage
can someone show me how to use LMV431 to generate -1.24 V from -5V?
below is how I use it for positive.
Thank you
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How to make this homemade enable? Need the OUT voltage to become -6 V when the enable voltage is turned on to 3.3 V
I don't need to be using a MOSFET, just figured that would be the way to go.
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Is it possible to share a common 0VDC (negative) between three DC switch mode power supplies - when two of them are in series?
I have a system that needs a 96VDC and 12VDC feed to operate.
I have a pair of Meanwell RSP-3000-48 power supplies tied together in parallel to supply 96V and a single Meanwell HLG-240-12 supplying ...
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Pull negative battery to ground with MOSFET
I have an input signal that goes from +10 V to ground and I want use it to pull the node "A" to ground.
The current will flow towards node "A" I was thinking using a NMOS, with in ...
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2
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595
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The minimum (negative) value of the exponent in decimal
I am learning computer architecture and organization. I am stuck in the following question. Can someone please help me?
For a floating-point representation with 35 bits in the mantissa and 15 bits in ...
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Are these 2 equations some of general formulas of infinitesimal length?
Given below. \$x\$ is a variable.
\$r:=\text{resistance between the nodes A and B}\$
\$l:=\text{length of the resistor }r\$
\$\rho:=\text{resistance per unit length of }r\$
\$\frac{1}{\rho'}:=\text{...
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Generate +/- voltage outputs using two boost converters?
I am working on a project to power some audio equipment that requires +/- 15V DC. Output current load is about 250mA, maximum. I am wondering if there’s any reason I couldn’t create this using two ...
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Coaxial cable in IT Earthing System
We are developing a shipboard system which needs to be connected in a IT network (Unearthed neutral). In order to comply with this scheme we need to avoid negative-grounded, as all the metal ...
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Op inverting amplefier circuit
i am using the LM741 amplefier
i want to invert a negative voltage (-10V)
to positive voltage (1V), my problem is :
i dont get the 1v DC at the output.
i get an ac signal at my oscilliscope.
and i ...
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Help explaining negative (ground) power connection through TV setup even though wire not connected?
After attempting to use a power inserted for the OTA antenna I discovered an unexpected problem. The inserter is powered by an UnGrounded Ac/DC adapter (Wal-wart as they are often called). All worked ...
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Switched-cap/charge pump only way to generate negative rail voltage for op-amp?
I need to design a daughterboard that gets mounted directly to a piezo mic to condition the signal before transmission. Part of the conditioning is a full wave rectification.
Thus, as you'd expect ...
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Frequency Conversion Product Lower than 0 Hz (Negative Frequency?)
If I have a bandwidth of frequencies from 200 to 500 Hz made from cosine waves and I mix this with a oscillator at 400 Hz which is also a cosine wave, the mathematics of conversions show that I will ...
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'Inverted' voltage follower with an opamp
I'm trying to figure out how I can achieve an 'inverted' voltage follower.
That is if I'm feeding 1V I output -1V, if I feed 2V, -2V etc.
I'm only going for positive tension to negative, I have +15 ...
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10mA inverting charge pump
I have limited knowledge of switch caps voltage inverters and charge pumps.
I need to generate -2.5V in my system capable of sourcing about 7.5mA.
I have MCU and two rails 3.3V and 5V.
So far, I ...
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MOSFET Gate driver - negative voltage with Zener circuit
I was reading about minimizing MOSFET switching loss when I came across an article by Texas Instrument on how to use negative voltage, instead of ground, to faster discharge MOSFET gate capacitance. ...
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Can a resistance be negative?
I have to calculate the value of a resistor so that my circuit has a certain equivalent resistance. This is the circuit, and here are the values:
...
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Verilog: Posedge sensitivity vs. If statement in Always block
I have recently completed a design that had run into timing issues (negative slack). The modules that were found to be troublesome, from the timing reports generated in Vivado 2017.4, are these ...
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303
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Negative 15V supply from 24Vdc
For my application I have two AD633 Analog Multipliers that need a ground referenced +-15V supply. I have a 24VDC and a 8 VDC supply to use, but i would prefer to use the 24V supply. I've looked at ...
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Why MOSFETs in Battery Management System are connected to negative terminal?
I have seen that the MOSFETs and current shunt resistors are connected to the negative terminals of the battery or the BMS. Is there any specific reason for this? Why aren't they connected to the ...
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Getting negative energy in a coil (RLC-circuit) after opening the switch
I've the following circuit:
simulate this circuit – Schematic created using CircuitLab
The switch was 'forever'closed and a certain time \$t=0\$ I open the switch. I tried to find the energy ...
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1k
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Negative voltage supply
I've been trying to make a active load that would use a very small resistor, around 10mOhm as a shunt resistor. I've figured out how to make it, it's a common circuit, however since I need to use ...
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123
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Get negative control voltage for a AS3310 chip
I'm trying to use a AS3310 chip to generate an envelope from a trigger/gate signal.
The AS3310 expects for the ADR (attack/decay/release) control voltage 0 to -5V - for the S (Sustain) 0 to +5V
I ...
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578
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Designing two stage CE amplifier with negative feedback [closed]
I'm trying to design two stage ce amplifier with negative feedback using 2n2222 transistors. The circuit must have certain voltage gain, Rin, Rout, Vcc, low and high frequency filter. This is the ...
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Op amp with feedback
simulate this circuit – Schematic created using CircuitLab
How to calculate Iout(current flowing through RL) of this circuit?
All Resistors are of same value except the load resistor.
Let the ...
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552
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Magic Eye Tuning Tube Variable Negative Voltage
I am thinking about several applications of magic eye tuning tubes as display pieces and had a question about their operation. I have attached a sample circuit from a datasheet for an EM84 tube. I ...
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Negative gate SCR
I've accidentally supplied the gate of an high power phase control thyristor (Vdrm=5200V and It(rms)=6500A) with a negative current (about two times the trigger current and four times the trigger ...
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2
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Operational amplifier and negative feedback
Let's consider an op-amp. In every book I've read till now, it is said that if we have:
negative feedback
finite output
then we have:
Vout = A * (v2 - v1) --> (v2 - v1) = Vout / A
If A is very ...
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What defines the sign of transistor rating values?
Here for example I have attached excerpts from two general purpose PNP transistor datasheets. One of them has negative values, other one positive.
I would like to understand what defines these values ...
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559
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LED indicators for 2 Positive voltages and 1 Negative
I have a seemingly simple question but I am getting stumped.
I have a power supply providing +12v +5v GND and -12v. I would like to have an LED for each input voltage showing that they are working ...
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Generate negative reference voltage
In my current design, I need to include force measurement. A301 sensor is selected for this. Now, in order to be able to have analog voltage proportional to the force applied, I need to have negative ...
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negative binary representation and 4 bit BCD represenation are similar
While representing negative numbers in binary we use MSB as sign indication.In BCD we use 4 bits to represent numbers 8-15. How does a device(ex:computer) decide whether its a negative number or a ...
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Applying negative voltage to CMOS chips
I have a situation where it's possible a negative voltage may appear on the power supply rails driving CMOS chips. The negative voltage will be very limited in current, fed through a resistor.
The ...
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Calculating power supply current output
I have a 15V power supply powering 2 Dc/dc converters that are the same. The converters are connected so that the outputs are 10V and -10V (the - terminal of the 10V converter is tied to the + ...
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Battery life and negative current
I am working on a battery powered project. With a multimeter I've been measuring current on the "positive" side of a module and observe 5μA.
However I thought to measure the "negative" side and was ...
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0
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Apply positive and negative voltage to component using single power supply [duplicate]
I have an electromagnet and a 12V power supply.
I would like to apply +12V to the electromagnet at some times and -12V at other times.
My current thought is to use four transistors (two NPN, two PNP) ...
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444
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Function Generator - Signal without Neg or Gnd reference
I have a new PC based function generator (very cheap), and an old BK Precision function generator. The old BK Precision can output a signal without the ground or negative reference lead from the BNC ...
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When do I connect to negative terminal or ground?
Easy question (or at least I think). I've installed a siren in my vehicle which calls to pull power direct from the 12 volt battery. I currently have the circuit completed by connecting to the ...
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Analysis of Negative Input Resistance Op Amp
simulate this circuit – Schematic created using CircuitLab
I'm having a difficult time analyzing the circuit shown and would appreciate some help. I'm just curious in order to get better at op ...
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Connection of dusl 12v NiCd battery packs [closed]
I have the 12v battery (it is actually 10 Ni-Cads in series), and, of course, it has a red wire coming from "+" and a black wire coming from "-".
However, on the schematic I am confused about whether ...
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Where is the positive and negative on an antenna?
What I am wondering is how to build an antenna. Upon unscrewing my telescopic antenna from it's base, I see only a metal screw base, nothing more. The F Connector has a positive and negative (or ...
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649
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Negative charge pump problem
I have an 18V 1.5A mains transformer (outputs around 30V peak with no load at 50Hz) followed by a full-bridge rectifier and a filter capacitor:
(there would be a schematic here if SE allowed me more ...
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3
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9k
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How does this Push-Pull amplifier work?
I'm reading about op-amp circuits that use negative feedback from this article (question no.19).
What confuses me is that the negative feedback for the Op-amp (which is being used to reduce ...
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651
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Why is it not possible to find pnp bipolar and n channel mosfet transistor arrays in IC package?
I use a lot of 2N3906 pnp bipolar transistors and 2N7002 n channel mosfets on my pcb. I was suprised to see that there are no cheap and commonly available IC packages for these common transistors as ...
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LM317 output voltage to 0 V with transformerless negative voltage created through a buck converter
I try to construct a shut down pin or a feature which can set the output of LM317 or LM78XX with negative voltage that is created through a transformerless buck converter.
A buck converter having ...
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How to connect earthed metal chassis to DC ground?
I have around 12 purely DC PCBs inside a metal case. Each has a MCU which connects to the main controller PCB with SPI or I2C. Each is powered by one shared ATX PSU which also sits inside of the case.
...
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