Linked Questions

1
vote
1answer
349 views

Switching Micro-controller from Adapter power to Battery [duplicate]

Currently I am running my micro-controller boards with power adapter(AC to DC). Now I am developing a system which senses AC power and sends me some signal when AC power is gone. The problem is I am ...
2
votes
2answers
328 views

Passive power supply OR-ing [duplicate]

I have several power sources (up to 4) going into a circuit and I would like to be able to power it with "automatic" selection. I have looked up power OR-ing and diodes are dissipating more power than ...
0
votes
1answer
49 views

Connecting two power supplies and preventing reverse feeding either [duplicate]

Is there any way to prevent current from passing through a certain wire without actually cutting off the power from that line. To be clear, I'm using 2 power source and because of "even with 0.0001v ...
-2
votes
0answers
29 views

Switching between two power sources (LiPo cells) [duplicate]

I'm building a circuit with a 2S or 3S LiPo as power supply. If a 2S LiPo is connected the circuit should be powered with 2S (7,2V). If a 3S LiPo is connected the circuit should be powered with the ...
48
votes
3answers
18k views

MOSFET: Why the drain and source are different?

Why the drain the source terminal of the MOSFET function differently while their physical structure is similar/symmetrical ? This is a MOSFET: You can see that the drain and source are similar. So ...
15
votes
3answers
21k views

Understanding Two MOSFET with sources connected

I am having problem understanding how this MOSFET configuration (used in battery charger) works? In this slide, what does it mean "blocking voltages in both directions while allowing ...
6
votes
3answers
29k views

Connecting two power supplies with same voltage rating to increase current output?

My h bridge requires 5v 1 amp. I have a 5v 500mA and another 5v 850mA power supply lying around. Can I join the +ve of both and send that signal to the h brdige so that it can have enough current of 1 ...
2
votes
2answers
4k views

How to Use Diode Oring to Switch between Two Power Sources? [duplicate]

I want to switch Power Between a AC/DC adapter which is supplying power to the circuit when AC power is On and when power loss power the circuit using 12V 7Ah Battery. AC/DC adapter is rated 12V 1Ah. ...
11
votes
1answer
2k views

Separating USB/MCU power buses

There are two power supply sources in the following diagram - USB and 12V. Only one power supply can be connected at the same time. I am trying to disable power to ...
0
votes
1answer
996 views

Feeding arduino with ATX standby power

I'm designing an Arduino shield to allow the Arduino to control, among other things, an ATX power supply -- I'm running GPIO pins to the PS_ON and P_OK pins of the ATX. I would like to be able to run ...
2
votes
2answers
143 views

Vcc and multiple USB Devices on one board

I'm working on a prototype board which has multiple USB device connectors (e.g. the one for a microcontroller thing I'm communicating with, and a second one for JTAG). Now I wonder how I should treat ...
0
votes
2answers
85 views

Automatically selection of voltage sources?

I'm trying to design a microcontroller board. There will be a main power connector and also an ISP programming port on my board. The microcontroller is running on 3.3V using a linear voltage regulator....
0
votes
1answer
40 views

Custom charger with solar cell

I want to make kind of autonomous power supply for my RPi. So that I am planning to use 12V solar cell and batteries for this project. Also I will use Arduino to controll all of this stuff - to ...
0
votes
1answer
30 views

Two power sources into appliance (12Vdc)

I am creating powering board for LED strips inside the cacti glass house. It consume 12V DC around 2 amps. I would like to power them up from battery (charged by solar, lead-acid battery 20Ah), but if ...