# Connecting H-bridge with current sensor

Joined Sep 17, 2015
15
Dear All
I am interested in connecting L-298 H-bridge IC with current sensing module ACS712-5A_A0330 to measure the current drawn by the motor and then pass the value to arduino. Can anybody let me know the schematic or how can i connect H-bridge to this current sensing module.

Joined Jul 18, 2013
23,362
The L298 already has current sensing in each side.
Max.

Joined Sep 17, 2015
15
The L298 already has current sensing in each side.
Max.
Can you please let me know the the schematics/circuit through which i can measure/send the current value of motor measure through L298N to arduino.

Joined Sep 17, 2015
15

Joined Jul 18, 2013
23,362
RSa, RSb on pins 1 & 15 are used to monitor the H bridge current when each side is conducting, this produces a small volt drop across the resistor that can be monitored by a analog input to your controller, if necessary an op amp can increase the output to a practical level as the value of RSa & RSb are typically very low.
If you Google this IC you most likely will get many examples, I do not use Arduino so I cannot be of much help there.
Others hear may offer some help on that score.
Max.

#### GopherT

Joined Nov 23, 2012
8,012
Dear Sir
I have attached the image of the IC i have, but i cannot understand how pin 1 and 15 can used for this purpose. Your assistance is required. Thanks.
So, assume your motor is a 12 V with current draw of 0 to 0.5 amps.

If 0.5 amps go through the sense resistor ( 1ohms), the voltage across that sense resistor will be 0.5A X 1 ohms = 0.5 volts.

Your arduino can read the pin1 of the L298 and a analogRead() command will see values of 0-1023 normally if all possible values are 0 to 5 volts. You will only get values of 0 to 102 if you are looking at 0 to 0.5V. If that resolution is good enough (about 1%) then that is all you need to do.

Just remember for the two "A" outputs, you monitor the "sense resistor" connected from pin 1 to ground at pin 1 of the L293 with arduino ADC (analogRead()) command.