Questions tagged [lm78xx]
LM78xx are a popular series of linear voltage regulators. To name a few 7805, 7809, 7810
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Solar cells with 5v regulator: would it supply more current than available?
I recently bought online three solar panels rated 6v x 500 mA for some circuits I had in mind. What I got instead were 12v cells, and I am certain they are rated 250mA, since the seller had those too.
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AC supply to digital output
I need to sample 8 power switches connected to 230 Volt supply. I want to record the status of these switch every 10 seconds and send to cloud for which I am using arduino with ethernet shield.
For ...
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xV input from a wall wart to +9v, -9v, +9v output
I am trying to modify a circuit Circuit schematic that requires three 9v batteries. Two to supply +9v/-9v for an lm358N opamp, the other +9v is to drive a DMM display.
I have dozens of wall warts of ...
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Switch Mode Alternative to LM7805/LM7905
I am attempting to design a dual rail power supply PCB for a university project. There are a number of restrictions - namely that it maintains > 80% efficiency regardless of the current draw. I was ...
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Question regarding the LM7810 voltage regulator [duplicate]
Is there a simple way I can hook up this regulator to reduce the maximum output current from the 1A rating down to a 500mA maximum output without affecting the 10vdc output?
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Making LM78xx fail safe against short, open, reverese bias, flyback, etc
I want to use LM78xx for various applications. What I am concerned about is its failure modes.
1. Failure to Short
Not shorting Vcc to ground!! I mean shorting V_input to V_output.
Assume that you ...
CommunityBot
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78L05 questions [duplicate]
What are the capacitors on the input and output of a 78L05 for?
I saw a lot of different schematics with a lot of different input and output capacitor values.
So now I am really confused, and I'm ...
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48V DC Power Supply Using LM7812 in Series
I want to create a 600W 48 VDC power supply with input taken from the line (220VAC) and so far the steps that I've had in my mind are:
Stepping-down the voltage to 15V using transformer with 3A ...
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7809 Linear Voltage Regulator Outputs in Series
I'm building a linear power supply that converts 120VAC mains voltage into multiple 9VDC, isolated outputs. I'm using this transformer that has the proper primary winding and 8 secondaries that I'll ...
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Can a 5V regulator connect directly to a voltage divider to obtain a 2V output?
In my circuit, a lm78l05 is used to provide +5V voltage to other parts. And now I need another +2V source to shift my input signal from +-2V to 0~4V as the ADC ad7682 limits the input signal range ...
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Can I obtain a new voltage source from outputs of two cascaded linear voltage regulators in practice?
I have a device which works with 7V. I have a 7812 and 7805 already running in the circuit. Can I use the outputs of this voltage regulators to feed the 7V device?
I know this is possible in theory. ...
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Is a full-wave rectifier really required with a 7810 regulator?
I'm possessed of a 12-0-12 500mA transformer.
To supply a stable 10V, I seek to connect a bridge rectifier, roughly filtered with a 1000uF/50V electrolytic capacitor and a 7810.
Is a bridge, or ...
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