Questions tagged [power-dissipation]
Anything related to power dissipation in electrical and electronic circuits and components, i.e. the process in which electrical energy is converted to heat when current flows through them.
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How to calculate power dissipation due to heat in an amplifer like LNA?
I'm trying to calculate how much power dissipated as heat in an amplifier like LNA.
Let's say a HBT device operates at 4.8 V with 80 mA operating current. Gain of the amplifier is 25 dB, OP1dB = 16 ...
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Mosfet Switching Energy
How can I calculate the energy required to switch a Mosfet knowing the peak power, and the drain to source capacitance?
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How to estimate the temperature rise in an enclosed space due to power dissipation? [duplicate]
I am planning a battery maintenance system that discharges a battery to a storage-compatible state of charge if the battery is not used for some time.
I would ideally like to dissipate 4kWh over 15 ...
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Reducing linear regulator heat via series resistor
I'm working on a project that uses four L293D motor drivers to control three stepper motors and one DC motor. Separately, there is also a small servo motor. The L293Ds receive a 6V motor supply ...
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How to calculate area using the V-Q Lissajous method
I am doing research on carbon conversion using the high voltage plasma method. In my research there is one problem, namely calculating the dissipation power where one of the parameters is determining ...
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Darlington configuration using BJTs [closed]
Does a Darlington configuration using two BJTs, say a BC548, override the total power they could dissipate?
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Power dissipation of PCB trace resistor in current limiting application
How to I calculate the width of a PCB trace to survive use as a current limiting sense resistor?
I'm looking at a low-side current limiting application like that shown in the schematic. The value of <...
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Finding memories power dissipation
Can someone tell me how to calculate the power dissipation of digital ICs like NAND Flash, QSPI NOR Flash and microcontrollers?
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Best way to heatsink many exposed copper polygons, avoiding electrical shorts
I'm working on a special type of lamp that uses 10 high-power SMD LEDs and 10 low-power TH LEDs. The heat dissipation will be an issue, so almost the entirety of the PCB is copper pours for the SMD ...
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How can I compare thermal behaviour between two packages with an equivalent resistors circuit?
I want to make a thermal analysis of QFP and BGA packages for a microcontroller. I know that in terms of thermal dissipation BGA is a worse election, but I want to know how much worse it is. I don't ...
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How much of the power drawn by a chip turns into heat?
If I have a circuit with a computing chip drawing 1W, how much of that gets turned into heat?
EDIT: I mean turned into heat 1. straight away (not in 1000 years) and 2. within the vicinity of the ...
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Is my heat sink properly sized for my LED strip?
I am looking for some help in sizing a heat sink for an LED horticulture light I am building. I will be attaching two Bridgelux BXEB-L1190U-30G3000-C-C3 LED strips side by side, link below to specs, ...
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Heater (resistor) combination to achieve specific power
I am designing a heating circuit composed of ceramic heating resistors.
I have a 24 V supply and I am limited to 3 A, which allows me to disipate total of 70W, which is my target.
I have a limited ...
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Help with determining power dissipation of resistor in parallel
I've been struggling with this question for a while for some reason, even though it seems much easier that it should be. The question asks for the power dissipated in resistor R (the one in the middle)...
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Thermal issues when converting high power using a low drop out linear regulator
We are looking to develop a circuit that will reduce 12 V to 5 V @ 5 A using a low drop out (LDO) linear regulator.
The best device that I found is the MIC29751-5.0WWT.
The heat parameters for this ...
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Can the heat be calculated in a DC voltage drop circuit?
Can the heat be calculated in a DC voltage drop circuit? 24 V, 150 Ω, ~100 mA. The first resistor was 1/2 W, the new one is 5 W. We want to know the expected heat for the new resistor. Looking to ...
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Heat management in multilayer board
I need some help designing proper thermal management for my board. It's a mixed analog-digital circuit, the analog part is noise sensitive. I have +/- analog supply, and a + digital supply. Several of ...
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AD22103 temperature sensor seems to be heating itself up
The picture shows a AD22103 sensor on a prototype board for a room temperature control. The sensor is intended to measure air temperature, not the board temperature. There was originally a ADT7410 ...
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Voltage regulator not heating up ... How?
I connected a L7805 to a water fountain that I measured to be consuming 0.1 A at 5 V to regulate power coming in from three 5 W, 12 V solar panels connected in parallel.
The regulator is not heating ...
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Junction temperature vs transient current
I'm using the OPA551PA amplifier to charge a capacitor to various voltages. After thermal calculations, the worst case scenario is depicted here. TA = 40C, Vin = 36V, Vout = 18V, Iload = 50mA. Under ...
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Chart/ table to visualize how hot a device is actually getting
Maybe my question will be a little funny. But it will be very helpful if you can give a little information about one thing. In electronics, we calculate power at various points/calculations to predict/...
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Which consumes less current in microcontrollers: Always HIGH pins or always LOW pins?
I am driving a P-MOSFET (IRLML6402) with ATtiny24A microcontroller. This is a battery powered system; that's why ATtiny is always on sleep. I originally configured a BJT which is driven by the ...
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Maximum allowable AC voltage for film capacitors as a function of frequency
For a project that I'm working on, I would like to generate an oscillating magnetic field. In order to achieve this, I would like to create a series LC circuit with multiple film capacitors in series ...
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SOA and varying VDS
In a hot-swap application the FET spends some time in the linear region/Saturation region before it moves into the ohmic region.
Here is a snippet of the turn on waveform seen for a FET:
Yellow is ...
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I calculated the power loss of a switching regulator and it doesn't match the datasheet. Am I missing something?
I'm trying to figure out how On Semi's LM2575D2T-5G is only 77% efficient. It's the fixed 5 V output version of the component.
The datasheet gives Vin = 12 V and Iload = 1 A. Based on this, power in = ...
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Is there a general rule to calculate heat dissipation of electronic equipment?
Is there a general rule for calculating heat dissipation in electronic equipment if it's not listed in the specs?
I have a couple of projects coming I'm working on that require this. For one situation ...
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How to calculate power dissipation for an MT3608L current-mode step-up converter?
I'm using an MT3608L with an input voltage of 12 V to create a voltage of 18 V using the below schematic. As this is a cutout of a larger schematic, the input voltage is applied to the top left wire, ...
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K155ID1 power dissipation
I build my own nixie clock with four digits (IN-14, 10k anode-resistor) with a seperate K155ID1-IC for each digit (so no multiplexing). Also, I am only using the 0-9 range, so every tube has one digit ...
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Efficient Voltage Divider Battery Monitoring for 42V system
I'm designing a system that is powered from a 10S2P LiPo battery pack and I was looking for an efficient way to monitor the battery level.
My microcontroller is 5V logic level, and I understand I can ...
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Is it bad practice to connect a heatsink to my PCB's ground plane?
So, basically, I have this LED project which is going to dissipate lots of heat (I am assuming close to 50W) inside a case. The LEDs themselves are on a separate aluminum board which will be attached ...
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Current limiter for VOD3120AB
I want to supply VOD3120AB with a voltage of 24v/2A from Power Supply. What is the value of the Resistor that I must add to the VCC of the VOD3120AB so that the VOD3120AB works properly?
Information ...
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Power loss and voltage drop for a parallel wiring system
I'm looking to power a 50W load approximately 140m away using 48V DC. At the far end I will use a DC-DC converter to convert this to 12VDC where it will power a small DC powered network switch I have.
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Calculate power dissipation of split-supply op amp for sinusoidal input
I want to calculate the total supply current and power dissipation of an op amp in a non-inverting voltage follower configuration with a split supply:
simulate this circuit – Schematic created ...
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Buck regulator thermals calculations
Schematic:
Specification:
Vin = 24V
Vout =5V
Iout max = 8A
Freq = 0.691 Mhz
Assumptions: Good layout and FETs mounted on 1-2 inch^2 of copper.
Calculations based on this doc: https://www.ti.com/lit/...
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Calculation of power dissipation of a MOSFET circuit
As a part of an assignment to design a common source amplifier, I came up with this circuit:
simulate this circuit – Schematic created using CircuitLab
The transistor is a 180nm technology with ...
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Using 110 Vac incandescent light bulb at 220 Vac with a series diode
I have a 110 Vac incandescent light bulb but I need to use it in 220 Vac.
If I add a diode in series with the bulb, the RMS power is the same as before but the peak value of voltage and current is ...
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About power dissipation of capacitors and inductors & I-V phase difference
For instance, The Art of Electronics (by Horowitz & Hill) states that
ideal capacitors cannot dissipate power, even though current can flow through them, because the voltage and current are 90° ...
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Does voltage drop resistor affect power dissipation?
I need to power an RFID from 24 V DC voltage. The RFID requires max. 9 V and max. 120 mA. The RFID suggests a 7809 linear voltage regulator. I thought too much and I want to use a 7809 because if I ...
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Mosfet power dissipation in this example
I am trying to design a buck regulator with the following specification:
Vin = 24V
Vout = 5V
I max = 8A
Fsw=300k. The load is basically a long strip of RGB LED's. Which in certain cases would be all ...
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Is there a "rule of thumb" for power dissipation of an enclosed circuit to help determine when to do a thorough analysis?
I'm starting a project and the electronics will be enclosed in a wood sign outside. Even though it's shaded, I'm concerned about heat buildup in the summer. Is there some rule of thumb that says if ...
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LM317 is dissipating too much power
I used an LM317 in my circuit to get a regulated 1.5 volts output from a 3.7 volt battery using two resistors (220 and 60 ohm.)
It worked fine, but the circuit dissipated too much power even when not ...
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How to calculate the pulsating current flowing through a shunt resistor?
If the current flowing through the shunt (0.5 ohm) is in pulsating form (PWM with 50% duty cycle and 100 Hz frequency,) how do I calculate power loss through shunt in order to choose proper for ...
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Buck / step down voltage in limited space
I am designing a small PCB. The supply voltage is 12V, but I also need 5V with supply of maximum 250mA.
The most obvious solution is to use voltage regulator - there are plenty of them and some like ...
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Calculation of heat generated by a battery pack
I have to calculate the heat generated by a 40 cell battery. The max. voltage is 4.2 V, nominal voltage is 3.7 V and the cell capacity is 1.5 Ah, discharging at a rate of 2 C.
If I calculate the heat ...
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Can PCB dissipate heat from MOSFET so that a heatsink is not needed
I am using a DMP3007 as a reverse polarity and over voltage MOSFET. The maximum planned load is 10 A and voltage may vary as the load is a constant current load.
simulate this circuit – ...
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With a constant-current, constant-voltage power supply, does the total length of the wire affect the heat produced per metre?
This seems like it should be obvious, but I can't seem to get my head around it.
If I have a length of wire 7 metres long and it has a total resistance across its whole length of 2 ohms, and I connect ...
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use of power dissipation in transistor and using higher current rated transistor
I am using using a PNP transistor in one of my application to switch on and off the boost convertor.
My requirement for collector current is 500mA.
My question is does it matter if I use 500mA/600mA/...
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SiC MOSFETS power dissipation; for heat sink sizing
I want to calculate the max. power dissipated for SiC Mosfet in a 6.6KW CLLLC resonant converter with full bridges on primary and secondary sides.
Let's consider the case when the input voltage is ...
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Is power dissipation for SMD resistor rated only for air dissipation or air + PCB?
I know that PCB with good copper area will dissipate much more heat than air surrounding the resistor. However, the datasheet for Yageo resistors is vague about whether the dissipation ratings take ...
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Very hot live pin on kettle plug
I moved my kettle just after boiling it yesterday and noticed the live pin was very hot. None of the other pins are hot. It's a bs 1363 type plug and socket. And a <2 year old kettle.
After a full ...
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