Isolated current sensing using LA25-NP

Another popular sensor used in my laboratory is current sensor LA25. In power electronic research, we tend to use sensor with safety standard. LA25 seem to fit in.

This sensor has nominal sensing current of 25A, and peak sensing current is 36A.

It needs +/- 15V supply voltage, and output current is 25mA.

It can be configured to change the sensing range in order to get more accurate result.

I draw each of the configuration on real picture as it will be more visual-able compared with datasheet.

25 AMP configuration

Pins 1 to 5 are connected together for "input sensed current", 

while pins 6 to 10 are connected for "output sensed current". 

M is the measurement, while +/- is for +/-15V supply.

12 AMP configuration

Pins 1 to 3 are connected together for "input sensed current", 

pins 4, 5, 8, 9, 10 are linked together. 

Last pins 6 and 7 are connected for "output sensed current".

8 AMP configuration

Pins 1, 2 are connected together for "input sensed current", 

pins 3, 9, 10 are connected together, 

pins 4, 5, 8 are connected.  

Last pins 6 and 7 are connected for "output sensed current".

6 AMP configuration

Pins 1 is for"input sensed current", 

pins 2, 10 are linked together, 

pins 3, 4, 9 are connected, 

pins 5, 7, 8 are also connected.  

Last pins 6 is for "output sensed current".

5 AMP configuration

Pin 1 for input,

Pin 6 for output,

Pins 2 and 10 are connected, pins 3 and 9 are connected, pins 4 and 8 are connected, pins 5 and 7 are connected.

The inner resistance change with each configuration, the lower the sensing range, the higher the internal resistance.

The supply voltage and output signal configuration are same as LV25.