Explain to me electronic switch and parasitic drains

How do i tell electronic switch from normal?

For eg, i have a nitecore d10, which drains my batt dry in weeks. My other eagletac d25a doesn't seem to drain my battery as it remains quite bright even after months, seems to be same for manker e11. I'm thinking of getting a klarus mi7 but read it has parasitic drain. Do enlighten me on this topic and thanks in advance!

JJ

A regoler switch is just close or open the circle so it's conduct ot not the electricity ant like that control the emiiter if its on or off

Electronic switch is not working like that it's controlling directly the driver so it alwyes must have a litell current so the driver could keep working and "know" is the switch was pressed

For know wat kind of switch it is you have few options
Regoler switch is alwyes turn on an off buy 1 press and have the option for half press
Electronic switch dont have helf switch ant has things like ling press and double,triple or more preses (like double press for strobe)

Good lights with electronic switch can have realy low parasitic drain and the battery can survive month before it's discharged

Moved to "Flashlight Electronics"

Moved this thread to Electronics for you, where it will have better visibility to all the circuit wizards of CPF ...

ruriimasu said:

How do i tell electronic switch from normal?

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Generally speaking, if the switch feels like it makes a very solid mechanical click (like a ballpoint pen) with a long movement of your finger required, it's a mechanical switch. If it makes a very soft click (like the buttons in your car) with very little finger movement, it's an electronic switch.

Electronic switches require an "always on" circuit, and if the circuit isn't designed properly it will bleed too much power. Most modern e-switch circuits no longer have the issue.

Think of electronic switches as being a primitive computer. The "computer" is always energized. Even when it is "asleep", it is consuming power monitoring what happens with the buttons.

How do I tell if a flashlight i see online have regular switch? Basically I don't like battery power to be consumed when I'm not using it.

Scratch "Primitive computer", as some LED drivers actually have full-blown embedded computer in a very small package (ranging from 2 x 2mm to 10 x 10mm depending on chip package).

However, think of regular switch as the house light switch; you either make or break the circuit by flicking the light switch as desired, it doesn't get that simple.

On the other hand, the electronic switch is almost never off (however in some case the CPU is actually halted to save on power when you turn the flashlight off), it requires what is known in electronics trade as "keep-alive power", which can be anywhere from 10 nanoamps to 10 milliamps, depending on microcontroller's node feature (most are 90 - 40 nanometers by now, while MCUs made on 32 - 20 nanometers high-dielectric metal gate process are very rare and expensive), and how you design the LED driver board will also obviously impact how much power you do use from state-0 standby (CPU halted state) to full power (LED set to 100% bightness). Software also matters a lot too. However some flashlights like Convoy L6 have both mechanical and electronic switches to curb on parasitic current.

EDITED: Regular mechanical switch is almost always loud, you can't miss that, by the way. You can compare it with clicky pen also.

ruriimasu said:

How do I tell if a flashlight i see online have regular switch? Basically I don't like battery power to be consumed when I'm not using it.

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List your lights and people here can help.

Chris

I've seen a stat that the e-switch in the Thrunite Tn4a would theoretically take 35 years to drain 4xaa. So that begs the question; why do otherwise good lights have these high drain switches?

Hugh Johnson said:

I've seen a stat that the e-switch in the Thrunite Tn4a would theoretically take 35 years to drain 4xaa. So that begs the question; why do otherwise good lights have these high drain switches?

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Theoretical and practice are different things. However, as for high drainage of the e-switches, that's a good question. However, regarding standby current, circuitry design is almost always to blame as some people opt to use very leaky MOSFET, or shoddy voltage regulator to feed MCU, ending up taxing the batteries even in the standby. Good component choice and proper design rule makes such a big difference.

Hi Chris,

I'm actually asking in preparation of buying a new single AA light. The reason I'm asking is because much of these newer designs are side switches (I hate them btw, easy to accidentally turn on and need to 'feel' in the dark). I narrowed down to Klarus Mi7 but read that it drains battery in weeks, even though unused.

ChrisGarrett said:

List your lights and people here can help.

Chris

Click to expand...

ruriimasu said:

Hi Chris,

I'm actually asking in preparation of buying a new single AA light. The reason I'm asking is because much of these newer designs are side switches (I hate them btw, easy to accidentally turn on and need to 'feel' in the dark). I narrowed down to Klarus Mi7 but read that it drains battery in weeks, even though unused.

Click to expand...

As a general rule (some exceptions) lights with side switches are electronic and lights with tailcap clickies are mechanical. Another way to tell is by the UI - anything that can sense a 'press and hold' is electronic.

I too dislike electronic switch lights.