A resistor is no good, the voltage will vary according to the current drawn through it - and a 7805 requires more than 6V input voltage to work. You can get LDO (Low Drop Out) regulators which would work with 6V input though.
usb is already at 5v ... do you mean you want to convert it to 6v?
with the voltages so close, it will probably work without any conversion, although you might want to use a self-resetting fuse or some other protection measure, to avoid burning out a usb port should something unexpected happen
Speakers must be powered from a power amplifier, not from a power supply.
5V is a very low voltage for a power amplifier.
With a 5V supply, an LM386 power amplifier IC provides only 0.11W into an 8 ohm speaker at clipping. A little louder than headphones.
With a 6V supply, it provides 0.2W.
With a 9V supply, it provides 0.45W.
Speakers must be powered from a power amplifier, not from a power supply.
5V is a very low voltage for a power amplifier.
With a 5V supply, an LM386 power amplifier IC provides only 0.11W into an 8 ohm speaker at clipping. A little louder than headphones.
With a 6V supply, it provides 0.2W.
With a 9V supply, it provides 0.45W.
actually I'm trying to connect HP speaker bar to another monitor. these HP speaker bar gets power from a usb cable. Unfortunatelly my monitor (eizo) gives 11.5V for speakers and i have some ac/dc power adapters that gives output 4.5, 6.0, .... 12V
well if you have 11.5v available, just slap a 7806 (with heatsink) on it, and you're done (a 7805 could also be used, noting guru's caution of lower output)
well if you have 11.5v available, just slap a 7806 (with heatsink) on it, and you're done (a 7805 could also be used, noting guru's caution of lower output)
Hi,
if your aim to to power an external amplifier like lm386 using supply +5v from usb port,(provided the current is within limit), whay you want any conversion at all-- use 5V as vcc for the amplifier. as Audioguru indicated the output power will be less. No point in dc- dc conversion in my opinion.