Well, I was going to call it a night a couple of hours ago, but I decided to make the new 5V Reg board.
This is pretty much the same design as the previous 5V regulator, it still uses an LM7805, still has one input but now has two outputs … mostly for mechanical stability when connected to a solderless breadboard. I have added a LED (and resistor) into the circuit so that the LED lights up when connected to power.
Here is the copper side of the board. it’s now 20mm x 25mm, so it’s bigger than the previous version. The increase in size is to accommodate the additional output pin header, the LED and the resistor.
When the power is disconnected, the LED (and the circuit) is idle.
Connected to power, the 3mm LED lights up.
I’ve tested the two pairs of output pin headers and they show 4.98V, the input pin header shows 8.96V, so it doesn’t look like the LED is affecting the output voltage (of course it shouldn’t) this just means that the battery will not last quite as long … it should still last a long time though, the battery is rated at 200 milliamp hours, the actual bleed time is dependent on the load amps. Either way … new power regulator … cool!
Here’s the evolution of the power regulator so far:
1st version of the regulator board …
2nd version of the regulator board …
Current version of the regulator board …
There’s still room for improvement for the board, I could go SMD and try to make it smaller, but then, SMD electrolytic capacitors aren’t much smaller and a SOT LM7805 isn’t that much smaller either … I think that I’m happy with the design as it is at the moment.
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