S
[email protected]
- Jan 1, 1970
- 0
Hi Folks
I'm trying to run a tiny 6 volt radio for as long as possible off a 12
volt car battery. I came across a 7806 but was disappointed to find
that it is nominally only 50% efficient. The heat dissipation (voltage
drop times load current) being much the same as the load (out-voltage
times load current)
I read some primer on dc-dc converters that claimed that synchronous
rectification could get to 95% efficiency. Is there some way to
achieve a reasonable efficiency here? I even thought about centre
tapping the 12 volt battery and using the two 6V halves in parallel.
I suspect I might need a diode in this circuit and that would not bode
well for the hopefully intermittent charging from a small solar panel
in Winter. I will also be running a 12V, 1 Watt LED from this battery
at night when the Sun definitely don't shine.
I'm worried that if there is a weeklong rain period with no charging,
I may flatten the battery too far.
Perhaps two or three car batteries in parallel might be a better bet,
but the ones I have are all different brands, sizes and ages, and
would definitely self-destruct by trying to charge the weaker ones
without diodes, but how do you rig up diodes to allow charging and
draining?
Thanks for any ideas or suggestions, jack
I'm trying to run a tiny 6 volt radio for as long as possible off a 12
volt car battery. I came across a 7806 but was disappointed to find
that it is nominally only 50% efficient. The heat dissipation (voltage
drop times load current) being much the same as the load (out-voltage
times load current)
I read some primer on dc-dc converters that claimed that synchronous
rectification could get to 95% efficiency. Is there some way to
achieve a reasonable efficiency here? I even thought about centre
tapping the 12 volt battery and using the two 6V halves in parallel.
I suspect I might need a diode in this circuit and that would not bode
well for the hopefully intermittent charging from a small solar panel
in Winter. I will also be running a 12V, 1 Watt LED from this battery
at night when the Sun definitely don't shine.
I'm worried that if there is a weeklong rain period with no charging,
I may flatten the battery too far.
Perhaps two or three car batteries in parallel might be a better bet,
but the ones I have are all different brands, sizes and ages, and
would definitely self-destruct by trying to charge the weaker ones
without diodes, but how do you rig up diodes to allow charging and
draining?
Thanks for any ideas or suggestions, jack