APM 1.0 Voltage Regulation Capacity?

The answer is no because you need to understand more how the circuit works. A linear 3 pin voltage regulator such as the 78XX series or the LM317 are limited to about 1 Amp MAX but only under some very hard to meet conditions. Linear regulators are basically a voltage divider and thus theorectically 50% or less efficient meaning they put off a lot of waste heat. The more power you draw or the higher the input voltage is than the output voltage, the worse the power disipation factor becomes. Basically, at 40Volt input-you can't draw more than a few micro-amps at best and the heatsink would be blazing hot and the device would go into shutdown. By my estimate, the Arduipilot has at least a 1/2 amp draw and more once you start adding all the sensors. You'll likely be at the 1amp draw which on paper seems fine, but without extreme heatsinking and just the general power waste anyway, it's not the recomended way. I know my ESC BEC (Battery Eliminator Circuit) or regulator supplying the Ardupilot is getting warm by my standards just in testing without spinning the motors. The power draw is really increased by all the regulators we already have in the circuit. There are several on the Ardupilot itself to provide 3.3 volts, and then just about every sensor has one too. Next comes the RC receiver with it's internal regulators and then finally telemetry which is a power hog too. The bottom line, it all adds up and at 50% or worse per device, a rather wasteful system, thus a final source regulator to the whole system is being abused current wise-and that's why a 317 or a 7805 cannot power the system.

You must go with a digital switch mode one capable of 3 amps and closer to 5 amps rating for safety. The higher the amp rating, the more efficient the regulator is (or that's the basic theory).

You need something like this IC instead: LM2567 3A step down digital regulator.

Or here's some info: http://www.eflight101.com/esc/bec/

— Eflight 101

Electric flight information and links to manufacturers, plans, information, etc.

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Vernon Barry February 14, 2012 at 1:05pm

The answer is no because you need to understand more how the circuit works. A linear 3 pin voltage regulator such as the 78XX series or the LM317 are limited to about 1 Amp MAX but only under some very hard to meet conditions. Linear regulators are basically a voltage divider and thus theorectically 50% or less efficient meaning they put off a lot of waste heat. The more power you draw or the higher the input voltage is than the output voltage, the worse the power disipation factor becomes. Basically, at 40Volt input-you can't draw more than a few micro-amps at best and the heatsink would be blazing hot and the device would go into shutdown. By my estimate, the Arduipilot has at least a 1/2 amp draw and more once you start adding all the sensors. You'll likely be at the 1amp draw which on paper seems fine, but without extreme heatsinking and just the general power waste anyway, it's not the recomended way. I know my ESC BEC (Battery Eliminator Circuit) or regulator supplying the Ardupilot is getting warm by my standards just in testing without spinning the motors. The power draw is really increased by all the regulators we already have in the circuit. There are several on the Ardupilot itself to provide 3.3 volts, and then just about every sensor has one too. Next comes the RC receiver with it's internal regulators and then finally telemetry which is a power hog too. The bottom line, it all adds up and at 50% or worse per device, a rather wasteful system, thus a final source regulator to the whole system is being abused current wise-and that's why a 317 or a 7805 cannot power the system.

You must go with a digital switch mode one capable of 3 amps and closer to 5 amps rating for safety. The higher the amp rating, the more efficient the regulator is (or that's the basic theory).

You need something like this IC instead: LM2567 3A step down digital regulator.

Or here's some info: http://www.eflight101.com/esc/bec/

— Eflight 101

Electric flight information and links to manufacturers, plans, information, etc.

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APM 1.0 Voltage Regulation Capacity?

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