Questions tagged [7805]
7805 Voltage Regulator IC is a member of 78xx series of fixed linear voltage regulator ICs.
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Power supply fluctuations. Bypass capacitor needed?
I am powering up a 5V device using a 12v DC 1A SMPS power supply. The 12V supply is connected to the 5V device through a 7805 voltage regulator. The device draws about 30mA when idle, but when it ...
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L7805 destroyed - why?
I used a L7805 to power a Raspberry PI and it worked for about 10 seconds then started to smoke and die.
L7805 is rated for 1.5A and 35V DC input. Power supply was 24V DC (was actually two plugin 12V ...
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How to measure AC and DC with oscilloscope
I'm a newbie with the oscilloscope. I have a digital RIGOL with two probes.
I'm testing a simple 12V AC to 5V DC converter.
I'm trying to measure the effect of the 7805 on the DC signal in output ...
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Can I use two 7805 ICs in parallel to get double current capacity?
I use a 7805 for a project where the circuit needs a higher current (~2.8 A) at 5 V. So I assume that if I use both ICs in parallel I can increase the maximum current capacity. Would it work?...
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Selecting the correct input/output capacitors for a 7805
So I've got a 7805 Regulator and I've been looking it up and each website says different info. I am using an input of 12V DC 1A Wall Adapter as an input supply.
www.adafruit.com Says
This ...
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LM78H05K How to use
I have bought the LM78H05K 5 V voltage regulator , for the 5v output.
My input voltage is 17 V DC. but unfortunately this component is in different shape. I have uploaded the image of the module. I ...
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Voltage drop in Vin of 7805 regulator when used with a Bridge rectifier and CT(Current Transformer)
I have a voltage regulator circuit powered by a CT. I rectify the output AC voltage to DC voltage and provide that as an input to the regulator L7805CV. My input voltage is about 7.20V When I connect ...
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2N2222 experiment is indicating incorrect gains
Okay, so I put a 20kΩ resistor between a 5V supply and the base of a 2N2222 with the collector connected directly to the 5V rail and emitter to ground. What I'd expect is that, roughly, 220μA (i.e. (...
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Going under specs for a linear regulator?
I have a Microchip PIC board (18F46K22) which has a VIN pin to connect to a power source (7vdc + supply).
What happen if I feed 3.3V to the VIN which goes through the 5V linear regulator (ST 78M05)?
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Connecting the linear regulator directly to AC line
There are several out of the shelf solutions: LR8 from Microchip (formaly known as Supertex product) and NCP785 from ON-Semi. The last one is able to handle up to 700 volts at the input which is ...
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Powering two circuits from a 9v battery
I am building an experimental percussion instrument. I have two circuits in it which are not connected to each other. One is a small linear fan speed regulator controlling a small motor, which ...
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Circuits And Voltage [closed]
simulate this circuit – Schematic created using CircuitLab
Please help.... I have an input of 7.5V but when it goes out of the circuit the voltage drops in 2.5V but i want 5V of output voltage ...
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Choosing bypass capacitors for successive linear regulators
Background:
I am reviewing my prototype PCB to iron out previous issues. The PCB is a Bluetooth data capture unit for liquid levels and flow. I am a software programmer by trade and I have some ...
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External power supply design (12V to 5V and 3.3V) for arduino based system
I am designing an embedded system having following components:
One arduino uno (~300-500mA 5V=2.5W)
One nodemcu (esp8266) (~300-500mA 3.3v=~2W)
One PAM8403 based audio amp board (3W output, so on 5V ...
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Controlling NiMH charging with power MOSFET: MOSFET before or after the linear regulator?
I am starting a project where I want to make a simple, Arduino-controlled NiMH battery charger. I imagine several iterations, but the first one will be really simple. It will charge at a constant ...
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