# How to calculate output of l298n

#### Man10

Joined Jul 31, 2018
105
I am planning to buy the l298n motor driver. I am just trying to make sure I know how to calculate the output current of the l298 motor driver. Output current depends on the load? I measured both the input current and the input voltage to the motor. According to ohm's law, the internal resistance of motor is 40 ohms? The measured voltage was 8 volts and the measured current was 0.2 amps? The motor is the load?
So if the input voltage to the motor is 4 volts, the output current is 0.1 amp?

Joined Jul 18, 2013
23,385
A DC brushed motor?
The current will depend on the load placed on the motor, there will be an initial inrush current when first energized until the motor is revolving.
The motor current with zero load will be relatively quite low.

#### MrChips

Joined Oct 2, 2009
23,960
Not for a motor.
A motor is an inductive load. The starting current will be much higher than the running current.
The running current increases with mechanical load on the motor.

Edit: Ah! Max beats me again.

#### Man10

Joined Jul 31, 2018
105
Not for a motor.
A motor is an inductive load. The starting current will be much higher than the running current.
The running current increases with mechanical load on the motor.

Edit: Ah! Max beats me again.
What is an inductive load?

Joined Jul 18, 2013
23,385
A load that possesses inductance!

#### LowQCab

Joined Nov 6, 2012
806
You shouldn't start with the Motor Driver Chip.
You should start with "what is the Mechanical-Torque-Load" and required RPM Range,
and then select a Motor that can comfortably handle that Torque and Speed,
then determine if you have an adequate Power-Supply to
provide for the maximum Voltage and Current requirements of the Motor,
and only then should you start thinking about the Electronic Control of the Motor's Output.