Questions tagged [leakage-current]
Leakage is the current across a boundary normally viewed as insulating, such as the spontaneous discharge of a charged capacitor, or the flow of current across a transistor in the "off" state or a reverse-polarized diode. Leakage current can also refer to the unwanted current that flows from a circuit in equipment to the chassis, or to ground. If equipment is not properly grounded, this current flows through other paths, such as the human body.
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How much leakage current is too much in a TFMR?
I have a 3-phase TFMR with 3 primary windings and 3 pairs of secondary windings. I'm trying to test the isolation between the secondary winding pairs.
To do this I shorted A1, B1, C1 and A2, B2, C2. I ...
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how to measure leakage current across a zener diode with a transimpedance op amp
I am trying to measure the leakage current of a SMF36CA zener diode. I am doing this with a transimpedance op amp (LMC6062IM/NOPB).
Attached is the circuit I am using. The amp and diode in the circuit ...
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Leakage current in supercapacitors stack
Given a circuit of four hybrid supercapacitors in series, connected in parallel with another branch of supercaps in series (4s, 2p), where the leakage current is illustrated as a parallel resistance ...
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Hipot results vs surface area
I trying to hipot test a 12"x12" metal with kapton layer. Different sizes of metal (e.g. 1"x1", 4"x4", banana plug) is placed on top of kapton tape. The bigger metal ...
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Is this a possible Leakage current problem
I have a question about the connection circuit between µ-controller and KSZ8851SNL.
Are the CSN and SO pins of the KSZ8851SNL tolerant inputs?
When Q1 is off, LAN3.3V was 0.9V in actual measurement. ...
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What is the reason for exponential decay of ceramic capacitor leakage current?
I came across two Tektronix documents describing how to measure leakage current. Both of them say that current decays exponentially, which I don't understand. I expect a constant leakage current ...
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How to find low DC leakage capacitors?
In some refdesign I'm following (for PoE), they ask to a 1nF capacitor to earth/chassis (not GND).
One of the global design constraints is to maintain DC-resistance of at least 20M between all ...
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Why is my 3-phase power giving me two 180 V phases and a 40 V phase?
I have 3-phase power hooked up to my building. I also have solar panels feeding the grid. Most of the power in the building is functioning normally. I tested the phases with a multimeter and got 120 - ...
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Residue voltage due to gate driver leakage current
I want to reduce the leakage current of a gate driver driving an IGBT as I have some residual voltage on the high voltage line LV for communication is on. The residual voltage on the high voltage line ...
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Can I make active devices share voltage equally using ad hoc shunt resistors?
I have 3 active devices in series, SCRs in this case but I'm guessing that's not important. Each is rated for 2.4 kV. The total voltage I will actually apply is 6.6 kV.
Leakage current is guaranteed ...
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Analog switch unpowered state
The board I am designing is a test board for another battery powered PCBA. I am using a MAX4737EUD+ and a TMUX1101DBVR in my project to switch signals and power to the PCBA under test. They are also ...
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Handling large current peaks on CR2032 battery
I’m designing a nRF52832 SOC based device and I came across this issue with energy buffering and battery voltage drop.
I am using a CR2032 battery, nRF52832 SoC and a VCNL3040 proximity sensor.
This ...
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Is there a formula for the current leakage of a Zener diode?
I have this setup:
The problem with this setup is that when there is a 3.2 V voltage drop acriss the 160 Ω (vertical) resistor, then there's NOT a 3.2 V voltage drop across the Zener diode, in ...
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Can I use a plastic water tube as resistance to protect bathing people within a safe voltage?
Suppose home water has a resistivity of 2 Ωm, home electricity is AC 220 V, and human body in shower has a resistance of 1 kΩ.
Then a resistance R = 8.2 kΩ, which is a plastic water pipe of 1.29 m in ...
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How do medical SMPS achieve lower Earth leakage compared to "regular" AC-DC SMPS?
When using a "regular" (i.e. not medical grade) AC-DC isolated SMPS in the following fashion, a strong mains common-mode voltage is created on the DC side due to - I believe - the stray ...
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Connection between chassis GND to circuit GND
I have two requirements to use a chassis
Reduce circuit board leakage
Dissipate heat
In my application I'm using the connection as shown below.
Here I have fixed the chassis over the SMPS through ...
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Does the gate leakage current increase or decrease the drain current in MOSFET?
I know that the gate leakage means that the electrons are injected from the gate metal into the channel, therefore the conventional current direction is from channel to the gate. From KCL, I think ...
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Controlling SMPS with SSR (Blinking SMPS)
I want to control AC for Meanwell RS-25-3.3 using SSR-25DA.
When SSR is off mode the SMPS keep blinking as in hiccup mode, I think.
I don’t think leakage current from SSR is too high to trigger this ...
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Leakage ADC value not accurate for same leakage current
I am trying to understand how this reference design works. This can be found here, Automotive High-Voltage and Isolation Leakage Measurements Reference Design
I have simulated it on LTSpice
For ...
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How to measure leakage current through a capacitor in a simulation?
I am trying to design a new capacitor and then measure the leakage current through it. First, I want to find a way to measure the leakage current through a capacitor. I am using a PDK which has real ...
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TVS leakage current below Vrm
The TVS leakage current is given in datasheets as Irm at Vrm.
Two related questions about TVS specifications:
How will the leakage current change if the voltage is less than Vrm (e.g. half)? Will it ...
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RCCB at inverter/power backup output
This question may be lame but I really need a solution. I am not an electrical engineer but asking this here to get help for my home RCCB setup.
I have an RCCB at the main output and it is working, ...
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What is the voltage at this pin when it is internally pulled high?
I am using a PHY that has internal pull-ups and pull-downs on certain pins.
On this particular pin, there is a pullup that the datasheet says can range from 33 kΩ to 93 kΩ.
For the entire range, I ...
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Trying to understand Output Leakage vs Input Current
I have a device (VSC8540) driving another device (LS1046). The driver specifies output leakage current as +/- 85uA. The receiver specifies input current as +/-50uA.
First of all, is the input current ...
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Differential current sensor probe- Ground leakage current measurement probe for oscilloscope
I would like to know what you use to measure differential current which is also leakage current sensing.
Background: In industry , the AC or DC current flowing from inverter/ converter needs to have ...
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TIDA-01513 Riso calculation
Can someone assist with getting the Riso value using the datasheet
HV_batt = 400V
ISO_NEG = 4.278V
Rns1+Rns2 = 1.2Mohm
Vref = 2.5V
Rs2 = 5kohm
Using the equation TI used, we get Riso = -68110.24 ohms, ...
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Isolation detection circuit design
I came across the TIDA-01513 ref design by TI. The site is found over here.
I have made a simulation of this design but I am not getting the desired results stated in the ref design.
According to the ...
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Why is my capacitors' leakage current much higher than it should be?
I have a capacitor bank consisting of five 3.3 mF electrolytic capacitors. (Itelcond 400 V 3300µF datasheet here.) The five capacitors are connected in parallel and there's a charging circuit with a ...
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Opamp Guard Polygon: Only in Top PCB layer or or all layers
I have an opamp circuit as shown below.
My board stack up is SIGNAL-GND-POWER-SIGNAL.
I am providing a polygon to Guard the trace which is going to non-inverting
the input of the opamp.
The guard ...
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Battery drain on a simple UPS circuit
I've got a question about this very simple 2 diode UPS circuit, using a non-rechargeable battery. Basically, the battery takes over the circuit when the external mains power supply is removed (...
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Insulation testing of chassis leakage current/voltage (Megohmmeter)
Previous post
I feel my original post was not asked in a correct manner. I previously said I wanted to detect voltage but it now appears I should be detecting current instead.
My setup still remains ...
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How to fix LED fixture not turning off completely when the switch is off
I have LED ceiling lights that are not completely turning off even when the switch is off.
Sometimes the brightness of the glow is just to much for me and finally decided to do something about it.
...
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Detecting enclosure voltage for batteries
I have made an enclosure out of metal that is used to enclose my battery pack. I have stacked this enclosure with 18650 lithium batteries to build up a battery pack (24V).
Every time an error is ...
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When talking of mains leakage current, presumably this is an AC phenomenon. Can it cancel and/or is it filterable?
I have recently learned that switching power supplies tend to push up to the limit of 3.5 mA leakage to the ground wire on the mains supply. Presumably this is entirely AC, 3.5 mA RMS, and there is no ...
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UK: is up to 2 V AC between ground and neutral to be expected in a house supply?
I am seeing around 2 V AC between ground and the neutral, circa 240 V AC to the live wire. Is this normal or does this indicate a weak ground or some leakage path between lines perhaps?
I have an ...
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What will happen if I use RCBO where there is no neutral in the system?
I need some help. Could you please go through the scenario and try to answer my query below?
This system is installed in a ship where there is no neutral connection available.
A 440V/220V step-down ...
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Decoupling Capacitor on GPIO instead of connected directly to battery
I am building a device that is for most of the time in sleep mode. When woken up, I am sending some BLE signals and use a LED. To support the battery I have a 2u2F capacitor.
But because my battery is ...
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How to test if a domestic 3 phase power company meter is reading wrong?
BACKGROUND:
Domestic 3 phase 220VAC supply in Thailand.
Power company meter is 4 wire GE 3 phase 15A/45A.
Massive power bills when mains breakers were turned off (back in home country for 9 months ...
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Will using this mains EMI filter exceed maximum earth leakage when used together with an AC/DC converter
For an industrial piece of equipment with AC power inlet, I want to use this internal AC/DC converter with a given maximum earth leakage current of 2 mA at 250VAC.
Now it was suggested to also use a ...
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Isolated voltage measurement with an ACS37800
I am measuring 250VAC with an ACS37800. It happens to be a PWM based output of a TRIAC. For testing purposes, I am varying the duty cycle and input voltage to validate the measurement circuitry. My ...
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What is the relation between reverse saturation current and leakage current in a BJT?
I have been studying Studying Donald Neamen's Electronic Circuits 4th edition and Sedra Smith's Microelectronics 7th edition for quite some time now. I have been self studying. After searching ...
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Why is my measured leakage current of the capacitors much lower than my calculated value?
This is more a theoretical question.
I have a DC circuit with multiple capacitors with different voltages.
Because I need to know how much current my circuit needs over a longer time, I calculated all ...
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Calculating capacitor leakage current
I'm trying to calculate the approximate leakage current for some capacitors I have. They are 5F 2.7v supercapacitors. I charged them up to 2.69v using a precision bench supply through a 68 ohm ...
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Alternatives for a physical relay to disconnect pins of an MCU board from testing jig?
There is a certain system (PCB) which is built around an ARM microcontroller. In order to test the system, I used a DAQ by National Instruments which is able to simulate various conditions (both ...
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Is it possible to make this BJT-based voltage limiter more \$\beta\$-independent and temperature stable?
The following circuit limits the rail voltage to slightly above Vref, by drawing a lot of current, when the rail exceeds Vref. The BUF Block represents a supply such as LDO, Reference or other ...
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Bench PSU leaking voltage to case and not working properly
Tl;dr at bottom
Recently I found old bench power supply in my closet and tried to test it but display kept on displaying 0.00v and 0.00a - the power supply is voltage and current regulated and has two ...
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Effect of regular PN junction diodes in series with Y caps on EMI circuit of 4 kW 400 V power supply?
I have to add diode in series with Y-cap on EMI to solve some other problem. I took this decision based on assumption EMI test will be for frequencies 150 kHz and more, for this frequency diode ...
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Can a diode reverse leakage current cause error in this circuit?
I want to measure C2 leakage current:
simulate this circuit – Schematic created using CircuitLab
C1 has a leakage current of its own, to prevent C1 leakage current cause error in the leakage ...
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Implications and cause for static discharge
For months, I've had a potential buildup culminating in static discharge when touching the chassis of my macbook pro at ONE location. No source could be identified (no ground leakage – I checked with ...
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Equivalent series resistance vs. parallel leakage conductance
I am studying a book called RF Circuit Design by Reinhold Ludwig and Gene Bogdanov (2nd Edition).
In the first chapter on capacitors, they introduce the loss tangent and equivalent series resistance, ...
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