"low-power" refers to components and circuits which are designed to have a lower power consumption than their common counterparts. This is most often a requirement because of limited available power, as in battery operated devices.
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votes
3answers
258 views
How would you detect vampire/standby power?
Is it possible to detect when a device is consuming power in a stand-by or nominally off state? For example if I leave my charger plugged in, detect that a small amount of current is being drawn and ...
6
votes
1answer
3k views
Some advice on charging circuit used in simple UPS
I have looked around for some way of having a 5 volt power supply that acts like a UPS.
Basically want to use a micro usb connector for +5 have a battery and li-ion or other charging circuit that ...
16
votes
3answers
1k views
Making a battery last a long time in a microcontroller circuit
I'm hoping to power an ATtiny85V for a nice long time on some small battery, probably a coin cell.
I've looked into the software side, and my code is watchdog timer driven, has unused analog and ...
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votes
11answers
748 views
Low power radio + microcontroller recommendation?
I'm searching for a low power system-on-chip that combines:
A processor (any achitecture)
A radio (any frequency/bitrate/tx power)
2 or more I/O pins (ADC would be a bonus)
Can anyone recommend a ...
18
votes
4answers
2k views
Why does a faster clock require more power?
If you overclock a microcontroller, it gets hot.
If you overclock a microcontroller, it needs more voltage.
In some abstract way it makes sense: it is doing more computation, so it needs more energy ...
8
votes
3answers
487 views
Do batteries last longer with constant current draw or spiky current draw?
Do batteries last longer with constant current draw or spiky current draw?
Or, as is implied by the accepted answer to
"Making a battery last a long time in a microcontroller circuit",
do some ...
4
votes
6answers
833 views
How to build an ultra-low power time counter?
Inspired by this question I would like to know how low power you could go with a counter + 32 kHz oscillator (possibly made by yourself).
I found a nice oscillator circuit on a BJT reportedly drawing ...
8
votes
1answer
185 views
LED current while off
I have a vague recollection that while off, a LED can actually receive light and generate a small current (in uA).
Is that correct? How does that work? What is the best way to prevent this?
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votes
5answers
1k views
simple, energy efficient circuit to make single IR LED blink
I'm using a 850nm IR LED (spec sheet), and in order to extend my battery life, I'd like to make the LED blink (UF 1.9 V, IF 100 mA).
I found a couple of links 1, 2, 3 but they either a) require two ...
1
vote
4answers
457 views
Measuring low current at very high speed
I have a circuit with a very-low-power Jennic JN5148 module with microcontroller and 2.4 GHz radio, and some low-power sensors.
I have to measure the supply current of all these components, in an ...
3
votes
2answers
902 views
USB / Battery Switchover Circuit
Background: I am a non-EE (an 0x11? :^) thrust into the world of embedded systems design. I started this project with a only college physics-level understanding of circuits, but I'm gradually ...
3
votes
3answers
358 views
Suggest a timer chip
I need to take voltage measurements separated by long delays (couple of hours) and beep a buzzer when voltage level is met.
Power consumption is important.
What i want is a simple timer chip like ...
3
votes
4answers
600 views
Recomendation for a digital inverter made of discrete components
I have a digital circuit in which I need only one logic inverter, and both PCB size and power consumption are serious constrains. So I thought about using a pair of complementary SMD MOSFETs (the ...
0
votes
4answers
214 views
Wake up MCU on UART RX data
I have several MCU's of which I cannot use the deep-sleep modes, because they cannot wake up on UART data coming in. Are there any components for sale which can solve this? I can imagine something ...
0
votes
2answers
209 views
Identify component in old West German flip clock
I recently got hold of three nice vintage flip clocks. No time keeping mechanism is present but there is something to advance the time on the clock. This mechanism has one major component labelled ...
