vibration / motion leds

[silverdale0247]

Hi can anyone help. I want to make a motion or vibration switched light. It is to go into a model train. I want it to be battery powered from a 3v circular battery and to power between 1 and 10 less
The idea is that when the train moves the lights come on then when the train stops the lights need to Stay on for around 5 mins but then go off to save on batteries and the need for an external switch

 

[alec_t]

Running 10 LEDs from a small coin-cell will flatten it in next to no time . If the LEDs are white ones you would probably need a DC-DC boost circuit to drive them.
What gauge is the model (which will determine component choice)?
Are you looking for a discrete-component solution, or an MCU one?
What is the LED spec?

 

[silverdale0247]

I would prefer a discrete one the less are in the case of the single led one. A 1.8mm 2.6v led.
In the case of the multi ones probably use say 8 3mm 2.6v
Due to size restrictions as these would be going in a 1/87 ho or 1/76 oo scale train

 

[alec_t]

Have you considered powering the LEDs from the track supply instead of a battery?

 

[silverdale0247]

Yes but that will require friction free contacts which are rather expensive. Also some of my older triang stock have plastic wheels and axles

 

[alec_t]

Are you able to work with small surface-mount components, e.g. SOIC-14 chips and SOT-23 transistors?
Could you fit two or three AAA cells instead of the 3V coin cell?
Would a delay before switch-off of less than 5 minutes be ok (it would prolong battery life and might simplify the circuit or reduce circuit/component size)?

 

[silverdale0247]

Hi yes I could fit two AAA batteries. A delay of 2-3 mins would be fine

 

[alec_t]

You could try this :-