Questions tagged [units]

A specified amount of a quantity (e.g. voltage, current, power, time, etc.) by comparison with which any other quantity of the same kind is measured or estimated. The standard system of units is the International System of Units (SI).

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LDO units for noise [duplicate]

In this Link, on page 6,they have mentioned the LDO noise in terms of uV/(sqrt)Hz. Can someone tell me what does this unit mean and how to understand this unit?
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Battery capacity in mWh instead of mAh [duplicate]

I know that the capacity of a battery is expressed in mAh, i.e. A/s (international system of units). Today I used a command in PowerShell (*) in order to get the battery capacity, but the unit of ...
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Why are we able to ignore the henries, Hz, farads, siemens and ohms when calculating the characteristic impedance of a transmission line? [closed]

I have seen calculations, and every time we just take the coefficents of these values and end up calculating a simple complex number. The units all equate to various exponents of area, second, metre ...
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Schematics Standard for Space between Value and Unit

On electrical schematics, is there a standard for whether there is a space between the numerical value and unit symbol? I can find standards that require it in general writing, but none that ...
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How to interpret the “surface power density” of a battery/capacitor

I’ve come across this research and one point of representing a power output confuses me: This enzymatic fuel cell is based on non-immobilized enzymes that exhibit a maximum power output of 0.8 mW cm−...
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1-dB compression point is in the range of -20 to -25 dBm

I am reading the Razavi's textbook RF Microelectronics 2nd edition p. 18. It says 1-dB compression point is typically in the range of -20 to -25 dBm (63.2 to 35.6 ...
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How to convert amplitude (V) to dB (V^2/Hz or V/sqrt(Hz) or V?)

I took the FFT of a signal and am currently plotting amplitude (V) vs. frequency (Hz). I'd like to change the Y-Axis units to dB. How would I go about doing this? What would be the units? It is from ...
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What is the difference between "Storage Temp", "Ambient Temp" and "Operating Temp" mean?

To my understanding, ambient temperature is the temperature of the surrounding area while the unit being worked on is powered. While operating temperature is the temperature of the unit itself under ...
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In semiconductor physics, how can we know which units to use for Boltzmann's constant?

I'm working through Example 3.9 from Sima Dimitrijev's Principles of Semiconductor Devices textbook, and I'm not sure how to know which units to use for k in solving for \$v_{th}\$ in part a. The ...
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capacitor unit is not specified

I am currently working on a circuit but I can't figure out the non-polarized capacitor values, since some of them are not clearly specified as unit magnitude. Some of them are: 100, 500, 180, 5.6, 56, ...
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How to recalculate amperes to amperes/micron (transistor characterstics)

I measured the transfer characteristic of P-type FET (so I have drain current versus gate voltage.) The authors usually present results in μA/μm (microampere/micron) versus V (volt.) Because I have ...
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How does Ohm disappear in noise/power spectral density unit?

Power spectral density is commonly expressed in Watts per Hertz (\$W \over Hz\$) or \$V \over \sqrt{Hz}\$. When I try to derive these for a resistor I get confused on the units. If we define noise ...
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What does Nu (ν) prefix mean?

Stumbled upon this in ZVN4525E6 datasheet: Zero Gate Voltage Drain Current (IDSS): 35 νA @ VDS = 250V, VGS = 0V The letter is U+03BD and it is not in any common unit prefixes that I know. My guess ...
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Units of PID for car' velocity?

I'd like to duple check from units of PID gains for the velocity of car. This my equations for PI controller V (m/s), kp (1/sec), ki(1/sec^2), kp' (radians/sec) , ki' (radians/sec^2) and kd (no unit)...
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What is the meaning of VFS

I am working with a Dataq DI-1100 whose specs tout: "The analog inputs offer a fixed measurement range of ±10VFS..." VFS looks like a unit, but I find the language confusing. Researching turns up ...
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How to convert between G and mV/g of sensitivity?

I cannot for the life of me understand how mV/g or LSB/g can be related to the g sensitivity. For example, how can I find 0.0025 G sensitivity accelerometer given the sensitivity in mV/g? I haven't ...
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analog values to ppm

How to transform a set of analog voltages from V to ppm/K? I have to use this to calculate the temperature coefficient of a bandgap. Is the derivative the same as the temperature coefficient ...
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Why is the Farad unit so large? [duplicate]

I have wondered this on and off for years, and was prompted to find out the answer: Any time I've seen capacitors, they're listed with milli- or pico-Farad ratings. I understand that, nowadays, we ...
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Compare white LED radiated optical power: lumens vs milliwatts

I'm trying to compare the brightness of various white LEDs, some of which are listed in lumens and others in milliWatts (this is milliwatts of optical output, not watts of electrical power consumption)...
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Inconsistency in Values of Laplace Transformed Current when Changing Units

I was trying to convert the units of the following current in Time Domain and Complex Frequency domain (s-domain): $$ i(t)=20\cdot e^{-t}H(t)\,\,\,\,\,\text{[mA,ms]} $$ Where \$\text{[mA, ms]}\$ ...
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What units are kpts?

I am parsing data from a Siglent SDS2000X oscilloscope. The first chunk (0x00 - 0x003) is for wave_length. The data sheet ...
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2 answers
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Can I represent the value by using this unit [closed]

I want to represent this value in a better way for my report. This value is 3.1x10^-4 the unit is dBi Can I rather represent this value using this: 310 udBi The u in udBi is micro dBi
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What are the units when solving Transmission Line iterativelly?

I would like to know the conductancee,\$C\$, and capacitance,\$G\$, of my lossy transmission line which is configured as an open circuit. In such a case, I know that the expression that defines the ...
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Altium designer, changing from imperic to metrics primitives won't work?

I'm using a trial on Altium, where for I guess support ignores me (Altium Designer version 19.0.14). (I really hope it's better for real users if someone can confirm that, it would be most ...
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Definition of \$ \frac{mm}{Ampere}\$ (unit of current sensitivity)?

I want to know how \$ \frac{mm}{Ampere}\$ (which is the unit of current sensitivity of PMMC instruments) is defined? i.e, How \$ mm \$ is defined in terms of \$ degrees\$ ? For eg.: \$ \frac{rad}{...
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What are these designations on a sensor datasheet?

I'm working with image sensor Anafocus Lince5M. In its datasheet there are some designations that I can't understand (underlined). What are these designations? And how to calculate threshold ...
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\$pV/\sqrt {Hz}\$ in Power Spectral Density

I am trying to plot a Noise Spectral Density from 10 kHz to 1 MHz. The Graph shows a cure which at 1 MHz the noise is 76 pV/rootHz. I am unable to understand that unit definition here. Becuase the ...
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5 votes
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Units of BJT parameters

Let's say the model is the Ebers-Moll model, but this obviously extends to other models: $$ I_{\mathrm{b}} = \frac{I_{\mathrm{s}}}{\beta_{\mathrm{f}}}\left(\mathrm{e}^{\frac{V_{\mathrm{be}}}{NV_{\...
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SENT protocol output unit is LSB. What does this mean?

I have read couple of datasheet of devices which uses SENT protocol. They define the output between 193 and 3896. The unit is LSB. I think that this does not mean least significant bit? Example: ...
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How much maximum electricity bill (units) can be generated on 2 KW connection?

I have got a bill of approx 14000 Units (50000 INR) for a month on 2kW connection. As per my analysis and understanding, it can't be more than 2 * 24 HRs * 30 Days = 1440. I think electricity meter ...
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What other units can influence the way a wire glows than watt? [closed]

I have a vape device with a mod that lets me configure the power I want to operate it with and also as an additional setting that is called vape strength which can be set to soft/medium/hard. When ...
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Pulse width modulation and textual expression of resulting stimulus level

So we have been using pulse width modulation (PWM) as a means to digitally change the driving voltage of vibration motors. Usually, afaik, the resulting voltage from PWM is expressed as %duty cycle ...
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Why do so many PCB-designers use non-metric units? [closed]

TLDR: Why do so many PCB-designers use non-metric units? Sorry for asking this closed question again: what is the advantage of non-metric units But I do not understand, and there is also no other ...
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What's the difference between measurement resolution and digits per second in time measuring devices

In time/frequency counters/analyzers in technical specifications you can almost always find resolution and digits per second values next to each other. What is the difference?
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What is the unit of measure for a region's power supply?

So, I'm casually perusing an old issue of Foreign Affairs magazine and encounter a paragraph concerning the ability of Brazil's electrical power generating plants to supply juice. Said paragraph ...
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Energy Consumption of AC Motors with same capacity and same hp

I have 2 3-phase motors with same capacity of 45kW, hp 60,rated Voltage is 415V, VFD 55kW connected separately to a Vessel Line that is used to mixing of few components.i.e, it looks like this. (I ...
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Altium Symbol Wizard only in imperial

We have now got Altium 17 installed and set up, and I've used it to make various schematics. One feature of the software is the Symbol Wizard for creating our own symbols for different components. It'...
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Convert VAh to kWh

Sorry, this might be a stupid question as I'm not an electrical person. I'm analyzing an electricity consumption dataset and the consumption is measured by apparent energy (VAh). How do I convert ...
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Olympus TG-Tracker : What does this data stand for?

I'm sorry if this comes to wrong forum, but here goes. I got this new action camera which tracks the following kind of data (edited): ...
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What is a term for voltage that does not involve the unit?

Basically the title. What is the term that means the same thing as "voltage", but does not invoke a specific unit (in this case, volts)?
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Joule-hour is Watts * 3600?

Maybe this is a dumb question, but I am trying to get my units straight. I have an electrical system which has its consumption metered every hour, so I need units that are graduated in hours. So, ...
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Sealed, long, thin glass tube with two wires and tiny filament - what is this?

I found this thing, and have no idea what it is. The tube is 30 mm long, about 5 mm in diameter. Both terminals are connected with two drops of glass. There seems to be a tiny wire or filament ...
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Is there a common message protocol for sensor data on top of MQTT-SN?

I want to communicate various sensor data in a network of sensors. I found MQTT and MQTT-SN as suitable protocols for that. The latter being better suited for sensor networks with support for ...
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Watt-squared-seconds: unit of safe operating area?

In the datasheet of Linear's LTC4364, page 15, the safe operating area (SOA) of a MOSFET is described as: For short duration transients of less than 100ms, MOSFET survival is increasingly a matter ...
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Help identifying resistor with arrow accross and capacitor with unit "kp" or "k" or value "5/6"

Can you please help me identity these symbols from a vintage (1960) diagram? The capacitors units are noted with "KP", sometimes just "K". What is the rectangle crossed with an arrow? It looks like a ...
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Testing an X2 capacitor with a capacimeter. Is it broken?

This came up as a comment in other question I posted, but I thought it could be of use for someone else if posted separately. I have an X2 cap rated ".47K275V~X2". Is that ...
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2 votes
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SI derived units: Another name for the Volt [closed]

\$ V = \frac{Kg \cdot m^2}{s^2A} \$ I know it's basic but I was having a hard time understanding the relationship between volts, ohms, watts, amps and ohms until I broke everything down into base ...
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6 votes
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Transform pulses per second (PPS) to RPM

I have a stepper motor that turns at 5000 PPS and has a step angle of 1.8º. What would be the formula to transform these PPS into RPM?
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What are the units in which a radio signal's strength is measured?

I'm kind of confused about which is the most correct unit when it comes to the measure of wireless signal's strength. It seems that the correct unit is V/m (usually expessed in dBuV/m), however it ...
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7 votes
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Misconceptions about PID Controllers

I'm currently designing an equivalent of the mass-spring-dashpot system, and during the design phase I realized I don't fully understand how PID controllers physically work. Below is an image, the ...
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