Vin Power Filter
Topic: Vin Power Filter
(Read 1 time)
Vin Power Filter
Sep 19, 2015, 06:10 pm
I haven't used a DUE before and am unsure of how to filter/isolate the Vin power connection.
What I desire is to have the DUE and pwm board and a dozen hobby servos (MG996R mostly) running off the same 7.2V NiMh 5300 mAHr battery.
I have some 2200 uF caps (looking for 4700's for a total of about 10,000uF) that I will mount on a DUE shield with a .1uF or so polyester cap in shunt. Grounds and power connection for the battery, DUE Vin line and servo board will all meet at the same point. Servos will start up at .2 sec intervals.
It looks to me that the DUE has some kind of cap and a diode on it's power in. I can't quite read the schematic.
I have considered adding an inline diode and another 2200UF cap at the DUE power in so the DUE line doesn't sag when the servos spike. The diode drop would take this below the 7V recommended though. I'm not sure why a DUE needs 7V for any reason other than it's 5V power out line which I don't need. All the peripherals are 3.3V.
Am I worried too little or too much about DUE power?
Should I use the diode isolation with cap?
I want to wire this up today.
Re: Vin Power Filter
Sep 20, 2015, 04:53 am
on the Arduino due, the 5V regulator provides power to the 3.3V regulator. The 5V and 3.3V regulators can provide 800 mW each. The 7V minimum, is for the 5V regulator.
you can provide 5V directly to the 5V pin and bypass the regulator. But you must provide your own 5V regulator.
how much power does your servos require. If the total power consumption is more than about 600 mW, you should consider using a external regulator. A decoupling capacitor is always recommended for noise reduction, Placed as close to the power drain as possible. but you should not need to do much more than that.