Why not just use a 5V wallwart?
I don't seem to be able to find the ATTiny's current consumption anywhere (at least not in a form I can recognise!), but the max load from the led is going to be 20mA.
Just by running at 1mHz and switching off the unused parts of the chip power consumption will be a lot less than your LED, maybe a milliamp or two. By sleeping in between LED updates you could get it down to microamps.
Hmmmm, so say I was able to reduce the power consumption of the chip down to say 10mA giving a total load, including the led, of 30mA. Would the simple zener/resistor plan using a 1/2 watt series resistor of 150R be suitable for my needs? (calculated values from an online zener diode resistor calculator - I'm lazy ) Or have I forgotten something?
I don't seem to be able to find the ATTiny's current consumption anywhere
QuoteI don't seem to be able to find the ATTiny's current consumption anywhere The datasheet is the best source for that.A rough estimate would be 20ma, worst case scenario. Typically a few ma.
Thanks dhenry that fits in well with Fungus's L78L05 suggestion - good shout Fungus .