Questions tagged [7805]
7805 Voltage Regulator IC is a member of 78xx series of fixed linear voltage regulator ICs.
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Logic level switch controlled via ground (0 V)
simulate this circuit – Schematic created using CircuitLab
My goal: to convert a ground signal pulse into a +5 V signal pulse.
My question: How on earth do I do this?
Backstory: My Jeep ZJ ...
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LM7805 Voltage Regulator stops working when input voltage increases
I have the following circuit:
simulate this circuit – Schematic created using CircuitLab
I designed the PCB, had it printed and now I am testing it.
When I power it up the following happens:
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4940v5 drop-in replacement for LM7805?
I am a novice who purchased several TO-220 L4940v5 chips thinking they were drop-in replacements for the inefficient TO-220 7805s that I've been using. But not a single one seems to work. No heat, ...
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Regulated Power Supply
I am supposed to simulate this circuit (regulated power supply 5V), however I am not understanding what's the point of the resistor R. Is it a load resistor? Cause i thought these needed to be before ...
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Feedback on astable 555 timer circuit to control MAC valve for turbo control
I have some questions and wanted to get feedback on this circuit I have put together. Basically to see if there is something I missed or obvious that I should change or should have designed ...
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Can I use any digital component to avoid 7805 killing my microcontroller directly when its ground is disconnected (hence 12v goes to uC directly)?
My idea is to have an intermediate cheap component that will blow-up before my uC if the voltage goes above 5v from 7805 (or even some fuse, but I am not sure if a fuse will blow-up with over-voltage ...
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Circuit for stabilizing the mini - 3 phase wind turbine output to 5 Volt using 7805 IC
I am trying to get some stable output from a Brushless power generator/motor/turbine which i purchased from Aliexpress
Mini Micro Small 3 Phase Turbine
To check if it works i tried to rotate it and ...
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Fluctuations in 7805 Regulator IC Output
I built an Arduino using ATmega328 on perfboard. To power it, I used an 8V adopter with a 7805 IC. But the ATmega328 IC started to reset randomly. After some efforts I figured out that the problem was ...
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Is it possible to use Ultrasonic sensor HC-SR04 in continuous power-on mode
I will be using Ultrasonic sensor HC-SR04 in water level measurement. I will be triggering the US sensor and getting back the time-pulse from it at very slow rate maybe once every minute. I want to ...
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Is it possible to use 7805 regulator without capacitors at its input and output pins?
I have to drive a magnetic buzzer whose current is 50mA and max. voltage is 6V. I will use 7805 regulator to drive it as my supply voltage is variable 9V to 24V DC. There will be another small load ...
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Voltage drop on system activation
My question is generic in nature about electronics system design. I am trying to put together an RC car which is powered by an AVR Atmega168 chip. It communicates through an HC-12 module and has a ...
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Current-limit circuit for 78XX voltage regulators
I need to find the value of Rsc and R1 in the following circuit:
In this circuit, Q1 is the high-current pass transistor. Its emitter-to-base resistor has been chosen to turn it on at a given load ...
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NodeMCU with JHD162A Lcd module display issue
I have uploaded a program to NodeMCU, to print "hello, world" on JHD162A 16x2 LCD module. But the text doesn't appear on the LCD display. Instead just black blocks appear on the first row on the LCD. ...
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Why peak output current is greater than short circuit output current in 7805 voltage regulator?
This is the datasheet of 7805 voltage regulator produced by "Continental Device India Limited".
Question:
Why is the peak output current greater than short circuit output current?
Shouldn't the ...
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H-bridge with 7815 regulator
Could anyone explain to me why my 7815 regulator gets hot and eventually blows up ??
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