Linked Questions
13 questions linked to/from switch between battery and usb power no microcontroller circuit
8
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4
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Switching between battery and USB using diode OR logic
I have a Raspberry Pi that is powered by a USB cable from a Samsung charger. Now since my college has frequent power cuts, I designed a basic switch to automatically switch between a portable mobile ...
- 183
7
votes
2
answers
16k
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Switch between battery and USB power
Following on an earlier question I am looking for a circuit where it powers from USB when it is available and uses the battery when USB is not plugged in.
I want voltage drop to be minimal, zero if ...
- 2,862
3
votes
1
answer
2k
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Power a circuit with power supply and USB port, my solution
I want to power a circuit I have from a dedicated power supply. But at the same time, I have a USB port that can also supply power but only when I decide to upload new firmware to a atmega32u2. Here ...
- 183
2
votes
2
answers
4k
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12V Battery Backup Supply for GPRS Tracker
I have little knowledge on electronics apart from following a few guides. I have made a few 7 segment displays, nothing complicated.
Recently my girlfriends car was stolen and she has an insurance ...
- 21
2
votes
1
answer
6k
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P-chanel MOSFET series configuration
Good day
I'm busy designing a small DC UPS to run some appliances when the power goes out. I am, however, having trouble with an element in the battery switch-over circuit.
I decided on using a ...
- 95
1
vote
3
answers
537
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Is this a Depletion MOSFET?
I am confused on whether this is a depletion or enchantment MOSFET and I am wondering if anyone could figure it out. I need a depletion MOSFET for my circuit and can't figure out if this MOSFET is one....
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1
vote
1
answer
554
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Choosing the right FET to switch between two sources
The circuit below is based on the answer to this question, which i find to be suitable for my application.
3.3VDC is the main supply for the circuit, with 3.6V 1/2AA battery for backup, as defined ...
- 783
1
vote
1
answer
634
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Intel Atom board (DN2800MT) power supply, can I add battery?
After reading through 20-something posts about 'car/12V/power supply/computer' I've still not found a definitive answer to what I'd like to try here. If this turns out to be a dupe after all, my ...
- 123
0
votes
3
answers
1k
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power selector switch [closed]
i'm still working on my usb meter.
I still have a problem in my design, I would like to implement an external power supply and a battery. I was looking for a circuit that would switch automatically ...
- 81
0
votes
1
answer
163
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What is the simplest and best device (or circuit) to stop the flow of current in a line when current in another line is present? [duplicate]
What is the simplest and best device (or circuit) to stop the flow of current in a 3.7V (2A) line when current in another 5V (2A) line is present?
Basically I want to make an UPS using a LiPo battery ...
- 103
0
votes
0
answers
24
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Input/output USB power flow control depending on battery powered or wired
This seems like a very basic problem but I cannot really find a solution or come up with one on my own. The setup is simple (also picture for clarity):
A circuit that takes 5V input
Put a UPS with ...
- 41
0
votes
0
answers
37
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LDO with 2 input sources [duplicate]
The following LDO is supplied from 2 input sources. BAT, which is a battery from 2.5-4.2V and VBUS, which is a power adapter voltage of 12V. My understanding is that a diode has a forward voltage drop ...
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-1
votes
1
answer
573
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Switching from battery to usb power source [duplicate]
I'm currently creating a small device to operate on a CR2032 battery when it is disconnected and a USB power when it is connected. I want the device to be powered by USB when it is connected, without ...
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