pbarrette
Enlightened
Hi Lunal_Tic,
I see that you're having problems determining exactly how you should be taking readings with your meter. I decided to draw up some simple diagrams to help you (and hopefully others) out.
This diagram shows how to connect the meter to measure the input voltage to the converter circuit (or Vin):
This one shows how to measure the output voltage to the LED (or Vout):
Now.. There are two different ways to measure the input and output current. The simple, less accurate way, and the slightly more complicated, more accurate way.
First, the simple way to measure the input current (Iin):
Now the simple way to measure the output current supplied to the LED (Iout):
Now.. The more complex way involves inserting a low value resistor in series with the circuit and measuring the voltage across the resistor. You can then use Ohm's Law to calculate the current from the voltage. The simplest way to do this is to use a 0.1ohm resistor, then multiply the number you see on the meter by 10.
For example, if you are using a 0.1-ohm resistor and you see "35mv" displayed on the meter, you can take (35*10) = 350, or 350mA.
To measure the current input to the converter (Iin) using this method, hook the meter up like this:
For the current output (Iout) to the LED, hook it up like this:
So...
I hope this helps you out,
pb
I see that you're having problems determining exactly how you should be taking readings with your meter. I decided to draw up some simple diagrams to help you (and hopefully others) out.
This diagram shows how to connect the meter to measure the input voltage to the converter circuit (or Vin):
This one shows how to measure the output voltage to the LED (or Vout):
Now.. There are two different ways to measure the input and output current. The simple, less accurate way, and the slightly more complicated, more accurate way.
First, the simple way to measure the input current (Iin):
Now the simple way to measure the output current supplied to the LED (Iout):
Now.. The more complex way involves inserting a low value resistor in series with the circuit and measuring the voltage across the resistor. You can then use Ohm's Law to calculate the current from the voltage. The simplest way to do this is to use a 0.1ohm resistor, then multiply the number you see on the meter by 10.
For example, if you are using a 0.1-ohm resistor and you see "35mv" displayed on the meter, you can take (35*10) = 350, or 350mA.
To measure the current input to the converter (Iin) using this method, hook the meter up like this:
For the current output (Iout) to the LED, hook it up like this:
So...
I hope this helps you out,
pb