Questions tagged [7805]
7805 Voltage Regulator IC is a member of 78xx series of fixed linear voltage regulator ICs.
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Right Way to Step Down a PWM Signal
I need to control 4 servos using a PLC that operates with 24V. The problem is that servos use only 5V. To accomplish this, I built a simple circuit using some 7805 and a large 1000 µF capacitor to ...
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In which option, the diode will make the lm78xx circuit safer
This image was taken from Fairchild's datasheet on lm78xx. I have already built a working example of it, but I am still thinking about adding some additional diode protection (D1, D2). Which option ...
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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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What are these parameters on the 7805 voltage regulator datasheet?
From the datasheet for the 7805 voltage regulator this information is available.
I have multiple questions about this information, which I haven't been able to find clear answers to on Google.
What ...
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LM7805 decoupling capacitors
Would it be possible to replace these combinations of ceramic and electrolytic capacitors with just a pair of low-ESR 10 μF ceramics?
Conversion from 12 V to 5 V, minimal consumption, only MAX485 ...
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PIC18F45Q43 44 pin TQFP power supply
I'm working on a project with PIC18F45Q43's 44 pin TQFP package. The PCB I designed had a power supply based on the 7805, but when I power the circuit; the PIC18F45Q43 burns out. I even tried powering ...
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All in one PCB mount buck converter? Sounds like snake oil
I am on the hunt to power an ESP8266 and a relay from 12V while keeping the PCB as small as possible.
I am trying to avoid having to SMD the parts and have been advised against the LM7805 route as ...
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BCD 7447 powered by 7805 drops voltage
I am trying to use a BCD converter 7447 to display numbers on a seven segment display. Even before I apply any inputs or outputs, I observe that the VCC voltage of the 7447 drops (which is powered by ...
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Which capacitors to use with voltage regulator IC such as 7805?
Many of the tutorials suggest to use a large smoothing capacitor (tens and even hundreds of uF) with a full wave rectifier but the datasheets of the voltage regulators and some tutorials suggest only ...
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External 5V sensors separate 5V regulator , Poly fuse or both?
I'm producing an Arduino project that has two 5V inductive proximity sensors placed outside the project box.
The project is powered by a Meanwell 12V power supply then to a Murata 5V DC-DC converter ...
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7805 voltage regulator reverse polarity
I'm working on a project for which I need to use a 7805 voltage regulator. I feed 9V to its input pin and power a 5V board with the output. However, when the board is connected to a computer, the ...
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How would a using a resistor and regulator together affect a circuit?
I'm having trouble understanding a concept.
Let's just say that I have a simple circuit made using a 15V power supply.
If I have a linear 7805 5V regulator connected along the circuit, and then add an ...
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12VAC-5VDC regulator, but L7805CV doesn't work properly
Hi everyone. I am trying to make 12VAC - 5VDC power supply. However when plugged in, voltage between L7805CV in - ground was 4V while output was 1V.
I have test 7805 separately and it works correctly ...
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Protecting regulator from alternate power supply
I'm designing a module built around a Teensy LC MCU which can either run off of Eurorack power (+12/gnd/-12) or USB (mainly during development). The Teensy wants 5V and regulates down to 3.3V onboard, ...
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Input voltage control by resistor, is this method is correct or not?
In my application I have a requirement to switch 40V to 5V with the help of a linear voltage regulator. My load circuit consumes approx 7 to 8 mA.
Due to the unavailability of any specific model of a ...
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