Questions tagged [lm78xx]
LM78xx are a popular series of linear voltage regulators. To name a few 7805, 7809, 7810
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Voltage regulator replacement
I have a gadget (a Sonar) that stopped working (doesn’t respond to power on, power led does not turn on) and opening it to look for the typical signs of failure I see an L7818 voltage regulator in TO-...
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Lm7812 circuit help
In circuit to get a steady 12v DC I don't understand the use of the capacitors. Can anyone help me?
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LM78xx Reverse Polarity and Reverse Bias
I'm building a circuit that will use a LM7805 and LM7812 to produce 5VDC and 12VDC respectively, with the input power being ~16VDC from an external wall wart.
I already fried one of each regulator ...
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LM7805 Voltage Drop too big
I setup the following circuit:
When I measure the voltage between GND and INPUT of the LM7805CV I have a voltage of 7.9V (around 8V as per power supply). But when I measure the output it is only 1.4V ...
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Connecting Voltage Regulators 7812 in Parallel for High Current [duplicate]
Could I use two L7812 voltage regulator ICs in parallel to get 12 volt and more current that with just one?
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LM338T Output to 5V issue with LM1085-IT 3.3V
I am using 12V , 2A DC power supply as an input to LM338T and LM1085-IT 3.3 , for 5V and 3.3V output respectively.
The issue i am facing here is when these both voltage regulators are connected in ...
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Does the output bypass capacitor of an LM7805 double as a decoupling capacitor?
I'm using a 5v linear regulator (specifically an LM7805) that outputs directly to an ATMEGA328P. According to the LM7805 datasheet (page 23) input and output bypass capacitors should be used, as seen ...
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Crude LM7809 9V NiMH charger
I want to charge my 9V NiMH cell with a LM7809. The problem is that I want to limit the current output to 20mA or 30mA. How can I limit the current output from that voltage regulator with simple ...
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What does the CT suffix stand for in voltage regulator?
Given a regulator such as the LM7812, what does the CT suffix stand for in a voltage regulator in Fairchild LM7812CT)?
I've googled and went through the related datasheets, but could not find the ...
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LM7805CV output voltage drop to 2.5v after connecting load
I've made a simple linear power supply for micro-controller with a transformer and LM7805CV as seen in the picture.
LM7805CV input voltage is 35V and output without load is 5V but after connecting a ...
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Do 74HCxx chips require a linear voltage generator?
Recently I've read a book that says it's absolutely necessary to use a linear voltage regulator like LM7805 in circuits that use any of 74HCxx chips (CMOS logical gates). I thought that this advice is ...
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Jumper out an LM7805
I have a 5V hobby circuit that will be externally powered from a wall wart, with way less than 1 amp. For full flexibility, I'm thinking of using a simple LM7805 regulator - but that has a 7V minimum. ...
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buck converter and regulator
First:
I want to use DC DC Stop Down Buck Converter, im using this one:
- https://www.aliexpress.com/item/10pcs-24V-12V-to-5V-3-3V-3V-DC-DC-1A-Step-Down-Converter-Voltage-Regulator/32671102728.html
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Running Regulator Under Voltage
Is there any disadvantage to running a Linear Regulator under the minimum voltage stated in the datasheet? For instance, In the datasheet of the LM7812C2T, it says the minimuim voltage in order to to ...
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Decoding power supply regulation (42V from 5V)
I am referring below schematic where 42V is generated from LM78L05 regulator IC. But I am not able to get how LM78L05 can generate 42V? Which concept is used to get such high voltage from 5V regulator ...
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