High Power H bridge schematic using MOSFETS

A high power h bridge is useful in driving high power motors and developing inverters. The high power MOSFETs IRFZ44 & IRF630 support up to 55V & 9A.

Components Needed



2 x BJT BC546

2 x Push buttons

1 x DC Motor

2 x 1M Ohm Resistor

1 x 1M Ohm Resistor

8 x 10K Ohm Resistor

2 x 330 Ohm Resistor

1 x Breadboard / Veroboard

Jumper wires

Simulation on Proteus

High Power H-bridge using IRFZ44 & IRF630

Simulation models of IRFZ44 and IRF630 MOSFETS are available in Proteus library and they can be used for developing a simulation of high power h bridge in Proteus.
The main advantage of simulating h bridge motor driver schematic on Proteus is that the design is editable, the user can change specifications of the h bridge circuit as needed. The simulation results can validate H-bridge functioning.

Troubleshooting Proteus “Timestep Too Small” Error

Proteus timestep too small errorProteus simulation is based on algorithms and it is precise for most of the designs. But in some cases, the results are different on hardware. Sometimes Proteus displays some unusual errors in schematic designs that contain MOSFETs. Even if any such error appears, it does not mean that your design will not work fine on hardware. Following are some common errors and details on how to get rid of these errors.

  • Simulation is not running in real time due to the excessive CPU load
  • Delmin increased to 1.77636e015 due to lack of time precision
  • Transient GMIN stepping at time = 4.02618
  • Timestep too small; timestep = 1.11e016: trouble with node

Such errors usually appear when two identical circuits are developed with 2 transistors. For example, in this case, the transistor Q1 & Q3 were supposed to have the same value (1M Ohm) but as we encountered same errors, we cleared these errors by changing the values to an extent that may not affect the functioning of this H-bridge design.

If any such errors are still encountered, no need to worry, the design will work fine on hardware however you can still get rid of this simulation error by changing the values of R13 and R14 a bit more. Make sure they are kept above 1M Ohm.

Applications of High Power H bridge

High power h bridge circuits are used for controlling high power DC motors and they are also used in inverters. Almost every robot that runs on a DC motor contains H-bridge. H-bridge enables the user to control the speed and direction of DC motors.


High Power H-bridge with MOSFET IRFZ44 & IRF630 – Proteus Simulation 

MOSFET IRFZ44 datasheet

MOSFET IRF630 datasheet

BJT BC546 datasheet


Let us know in comments if you like this design or have any queries!