Is there a simple way to increase Spark's output voltage?

General
1

I know this is supposedly a basic electronic question, but I have another module that works at 5V. Can that be achieved by combining capacitors or regulator to raise the voltage temporarily to feed the module (and a motor)?

2

How do you power your Core?
The usual way to go is to use a Core GPIO pin to switch a transistor (bipolar or FET) which then switches the supply power.
This way the maximum power you can use is not dependent on the Core but on your power supply.

Even if you used a step-up converter to increase the voltage of one of the GPIOs, you would not be happy, since stepping up the voltage comes inevitably with loosing current, which is not to fat on a GPIO anyway (the power as product of voltage * current will not be increased by stepping up the voltage).

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3

Thanks @cruffR. On the other hand, I can input 5V to VIN and can separately power the motor and the module with the same source, provided they’re isolated from the core.

4

That's right. You can run the Core, your other module(s) and motor(s) from the same 5V and GND rails.

But what do you mean with:

since the Core and your other components share the same power rails?

The only thing you have to watch is, that you don't apply higher voltages to or draw higher currents from the GPIOs than what they are built for - but no need for isolation.

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5

What sensors and motors would you like to use? we can check what you need… you may not need anything depending on the sensor

you can get logic level translators that change between 3.3 and 5v. something like this

to hook up a motor you will need a driver. if its a small motor then something like this:

Some of the spark pins are 5v tolerant, meaning you can connect them to a sensor that outputs 5v. In the docs you will find out which ones are OK to use… http://docs.spark.io/hardware/#spark-core-datasheet-pins-and-i-o

But make sure you ask if you are unsure, most of the guys here are pretty helpful!

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6

@ScruffR what I meant was if I have a device says a motor that is taking 5V from the external source and outputting 5V, I should take good care of using the right pin on the core to control it since not all can take 5V (or more).

7

I see :eyes:!
You’re right, only some of the GPIOs can cope with 5V (but not more!).
And if you are not 100% certain that the output will not exceed 5.0V, you’d better throw in two more resistors as a voltage devider, to protect your precious Core :wink:

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