Questions tagged [diode-clamp]
The diode-clamp tag has no usage guidance.
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Diode-connected BJT vs base-emitter BJT diode vs diode
I was having a look at the circuit design of Keithley 236 SMU. You can find this part of the circuit in the Keithley 236 Service Manual.
Q47 is a BJT. Only the base and emitter are connected, which ...
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How can you block the parasitic body diode in digital CMOS I/O IC design?
I've been screwing around with IBIS models lately and came across something that left me scratching my head. First, the generic model structure for the semiconductor portions of an IBIS I/O looks ...
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MCU working at 3.3V and RS485 driver at 5V - how does this circuit work?
I was looking for a "quick and dirty" solution in order to work with MAX487 (5V) and my ESP32 MCU.
I know that Maxim integrated produces the MAX3485 and MAX3483 that are specifically ...
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How is energy conserved in an LC tank with voltage offset?
Consider an ideal LC tank oscillator offset by an ideal battery*:
The core question is this: is the energy balance here maintained by the charge-voltage relationship of the battery? Energy seems to ...
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How much current can opamps' integrated ESD diodes carry during an ESD strike?
So the basic answer to such kinds of questions is usually: "If nothing is specified in the datasheet, assume the most conservative rating!"
However, the datasheets usually only mention the ...
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Limit voltage follower output using Zener diode
I created a voltage follower/buffer for a first stage transimpedance amplifier and want to limit its maximum output voltage to roughly 3.3 V to protect the following ADC from voltage spikes.
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FPGA over-voltage protection for input trigger signal
I don't have much experience with PCB design, but I am currently designing one to connect together several components for a work project. One of these components is connecting an external trigger ...
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Using a diode to clamp a 24V logic output to 5V
I have a controller board (the Teknic ClearCore) in which output signals are pulled up to 24VDC. I am trying to interface with a TLC5947 LED driver IC rated at 5V maximum control input voltage.
The ...
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Can a normal diode like 1N4148WS use for voltage suppressor?
Currently, Im building a solar mppt charger circuit from LTC4013 Analog devices. Here is the datasheet: LTC4013 datasheet
Here is the schematic that Im working on:
I have a confusion on the diode ...
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Negative peak clamping circuit
The picture shows a clamper that clamps the negative voltage peak of a signal to -5 volts. I have two questions:
1- What is the function of the 15 volts battery ? It says that diode does not turn on ...
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How does the "zero current detection circuit" work?
This question refers to the L6562A PFC driver. My problem comes from the following highlighted text from the AN2761 application note.
I can't understand the reason for 1.4V.
What's the meaning of &...
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clamping the amplitude of a wave to certain level
I'm trying to prevent a wave form from exceeding 10V.p.p.
I tried various things, but ... what the correct way to do it?
this clamps a 11V signal to +/- 900 mV ... and converts a triangle to square.
...
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Voltage clamping for 28V nominal circuit
I am using a Vishay SIP32430 load switch for a 28VDC nominal input design. The absolute maximum rating for Vin is +30VDC. My input voltage will be nominal +28VDC, but short duration, low energy ...
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Can a ggNMOS be implemented discretely on a PCB?
Reading this answer, I ran across the ggNMOS for ESD protection.
https://electronics.stackexchange.com/a/576935/166672
Reading on the web a little, it seems that this is only used inside of an IC, not ...
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Clamping to rails of an unpowered circuit?
Clamping diodes are a common way to limit an input to a safe voltage range: if the input goes below 0V or above 3.3V, one of the diodes begins to conduct and clamps the input to (roughly) the rails.
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Transformer surge protection with MOSFETS
I'm trying to come up with a good solution to protect a 48VAC circuit against power spikes from the transformer when the load is suddenly disconnected.
Since I have a bunch of MOSFETs and Zeners at ...
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How to build an "instantaneous" clamper circuit [closed]
I am asked to clamp a signal 5sin(ωt) V with frequency of 1 kHz to a DC level of 2 V and -4 V. I already built circuits that can do that. But my professor says that the graphs should be exactly like ...
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Zener diode - Zener voltage vs reverse voltage specification
This may be a very simple question with a straight-forward answer, but I cannot get a clear answer on this.
Consider the following Zener diode. The table on page 2 lists a column for Zener voltage \$...
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TVS diode specs - clamping voltage lower than breakdown voltage?
Having read this app note (and a few others) and quite a number of TVS datasheets, I came across one that is bugging me a bit.
All of the TVS datasheets that I have read so far describe the the ...
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ADC Clamping Rrotection Circuit with Dual serial Diodes - Formula proof
I am trying to undestand and calculate why in the first circuit we measure 5.7Volt (if forward noltage diode is 0.7Volt) and not 12V. I used the Superposition Theorem which first I replaced the Vcc ...
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Troubleshooting DTL NOT gate circuit design
My guide says that the following diagram is a DTL NOT gate. Its output is a LED.
For learning purposes, I tested it via a simulator. The measured current is not really significant to power on the ...
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DRL AND gate circuit design
I have a guide stating that the following diagram represents a DRL AND gate:
Suppose that both A and B have 5-V inputs with a corresponding switch. I tried to simulate it for learning purposes and ...
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Is there any way to have a diode that have very small resistance from reverse path?
I'm trying to find a way so I will always have close to 0V at the measurement point (above the diode), when I have 0V as input. ...
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Do they make anti-parallel diodes in 2-lead packages?
Sometimes diodes in an anti-parallel configuration are used on the inputs to high-gain instrumentation amplifiers in order to protect against large differential voltages.
Does anyone know if the ...
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How do I create a secure clamping circuit?
Clamping is good for transients, e.g voltage peaks. But two issues with clamping is that if you have a linear voltage regulator attached to 3.3v and 3.3v is the voltage regulator output, then that ...
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A circuit that can clip a high voltage/ low current signal input to an Esp32?
I have a program for an Esp32 development board which detects the ignition spark from an engine and converts the frequency of the ignition to an engine RPM reading. The high voltage input peaks at ...
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Feedback on converting signal from 3.5mm jack to ADC on STM32 Bluepill
I'd like some feedback on my circuit. My goal is to convert an audio signal coming out of my laptop's 3.5mm jack (using a sin generator at max volume gives me about a ±1.5V wave) to digital using the ...
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Is ADC over-voltage protection needed when input isn't external?
In a situation where an ADC is measuring an internal voltage node rather than an external input (where one has little control over input voltage), does one need to implement some over voltage ...
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How to create an LTspice model for 1N4733A Zener Diode?
I'm new to LTspice. I'm using EveryCircuit as a crutch and would like to run my circuit simulation in LTspice to compare simulation results.
I've built a basic circuit to understand how a zener diode ...
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Can I assume input protection diodes in all modern ICs, even when not mentioned in the datasheet?
I use the A3906 motor driver on a board supplied by 8V. The µC on the board is supplied by 3.3V and is connected to the A3906 via the logic pins. I realised this is a potential pitfall, when supplying ...
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Clamper Circuit Without A Resistor Analysis
simulate this circuit – Schematic created using CircuitLab
We were given this clamping circuit and were tasked to plot Vc and Vout for varying input. The only given quantities are the forward ...
user263783
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Best design practice for relying on IC input diode current clamping?
I have a question about what the "best design practice is" for using ICs with current clamping diodes. Take for example the following IC: CD74AC251M (datasheet : https://www.digikey.com/...
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How do these Zener diodes limit the maximum voltage seen by other circuit components?
This schematic is given in Texas Instrument's AN-1533 Application Note (Over Voltage Protection Circuit for Automotive Load Dump)
On page 4, the author says that the D3 Zener prevents the cathode of ...
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Use of clamp diode in ULN2003A
I'm planning to use a ULN2003A 7-channel Darlington driver (datasheet) to control 4 to 7 LEDs in common-anode configuration from a Teensy MCU:
(The "trident" is a common-anode RGB LED).
The ...
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How to select clamping diodes
I have a current sense amplifier (TI INA303, the 50V/V gain version) that I want to read with a microcontroller. I've looked all over the place trying to find how to select the proper clamping diodes ...
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Class C Amplifier: Calculating the base resistor
I've built a Class C amplifier for educational purposes and believe I understand the major concepts on how it works. The only piece I'm struggling with is how to calculate for the base resistor. From ...
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USB supply protection using shotkey diode
Here is the atached schematic of the clamping diode condition. Isolated the connection to contoller and kept the end open. When USB input is varied above 5V the expected output is diode cathode ...
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Diode voltage for small signal model what is the small signal component v_d [closed]
What is the small signal component v_d in this graph? Since they say \$V_D = v_D + v_d \$
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Understanding TVS diodes in this application
From this Reference Design you can see they use two TVS diodes at the gate of the first FET to clamp voltages greater than 500V. They do the same in this other Reference Design.
So basically my ...
user115094
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Electrostatic protection - input and output ESD protection added to op amp w/built-in ESD
I have an op amp circuit using the OPA2626 that has a built-in input/output ESD protection of +/-3000V human body model. The circuit is 3.3V single supply, non-inverting, with only an external ...
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How to protect an input from ESD?
I would like to protect the input of a sensor (reference : MAX30001) from ESD.
In the datasheet, they say that the absolute maximum rating of this input is -0.3 V < Vinput < 2 V.
Do I have ...
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Understanding this clamp network
The circuit below is from this Reference Design.
I want to understand the clamp network at the input. How is VGS of Q1 kept at a safe level?
user115094
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What is the purpose of clamping the gate and source of a mosfet
Is clamping the gate and source of a MOSFET really important? I have seen this in some articles and some datasheets of MOSFETs where they have built in clamping.
As far as i know they are used for ...
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This clamping circuit output is -ve compared to what is expected?
Clock Pulse of Vpeak =10. Providing that the first cycle is -ve why does the output in first is -20 then 0 then -20 and so on? I expected it to be 0 and 20.
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Polarity of input signal and capacitor in voltage clamper
I am stuck at understanding how voltages add up in a voltage clamper, reading through Learning About Electronics - Diode Clamper and All About Circuits - Voltage Clamper, and also YouTube a few ...
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Buck regulator maximum supply voltage VS. voltage spikes at input where we have a TVS diode
Currently I'm using a buck switching regulator AOZ1284PI of Alpha & Omega Semiconductor to generate a 5V supply from a 12V input of a lead-acid sealed battery, and I plan to use AOZ1284PI again on ...
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How is dc restorer circuit used for PWM demodulation/detection?
In the Microelectronics Circuits textbook by Sedra & Smith, it is said that:
As an application, consider a pulse signal being transmitted through a capacitively coupled or ac-coupled system. ...
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Ethernet POE voltage measurement to determine Voltage clamping between line ot Ground
I am planning on using a tvs diode to clamp power peak to protect network switch; the Port is POE. The issue is that when I measure the voltage of ethernet line to ground, I get around 0.6V. When I ...
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How to choose the correct TVS diode and how to size it?
So I was thinking about transient suppression and I found TVS diodes. I was wondering how to choose the correct TVS diode since they have 3 voltage parameters:
Vc --> clamping voltage, voltage I ...
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Designing a clipper circuit
Design a clipper circuit using 1N4148 general purpose diodes and a R = 1 kΩ to clip input signal voltages that are above 5.7 V or less than −0.7 V. Below is my schematic in which Vo<=Vdo + 5V and ...
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