Description
The brushless DC (BLDC) motor control design example describes how to connect and control up to four brushless DC motors using a single NXP microcontroller from the ARM968-based LPC2900 series, making this a low cost solution. Four dedicated motor control PWM blocks keep the CPU load low while running four motors. This allows the microcontroller to still perform other tasks in
Hardware used
- Hitex LPC2939 or LPC2929 evaluation board
- Hitex BLDC motor control extension board (4x)
- Interface board
- Maxon EC32 80W brushless servo motor with Quadrature Encoder Interface (QEI)
Three of the Hitex BLDC motor boards are driven as-is (spinning their on-board motors). The fourth board is driving the Maxon EC32 motor using the quadrature encoder interface. The interface board is used to create the correct pin-out that makes it possible to connect the four motor control extension boards to the LPC29xx evaluation board.
Block Diagram

Documentation
Products
Below are recommended microcontrollers for use in BLDC motor control applications.
Comparison Table
| Product | Pins | On-Chip Flash | On-Chip RAM | Comments |
|---|
| LPC2939 | 208 | 768KB | 56KB | Base microcontroller used in the design example. |
| LPC2930 | 208 | 0KB | 56KB | A lower-cost microcontroller with the same amount of pins but without on-chip flash memory. |
| LPC2929 | 144 | 768KB | 56KB | Same on-chip memory as on the LPC2939 but in a smaller package and without USB Host functionality. |
| LPC2927 | 144 | 512KB | 56KB | Same as LPC2929 but with less on-chip flash memory. |
More Information
Image

BLDC Motor Control Demo at ESC SV 2009
Schematics
- LPC2939 Evaluation Board
- BLDC Motor Control Extension Board
- Interface Board
Example Code
Bill of Materials
Disclaimer
This design example shows possible hardware and software techniques used to implement the design. It is imperative that the viewer use sound engineering judgment in determining the fitness of this design example for any particular application. This design example may include information from 3rd parties and/or information which may require further licensing or otherwise. Additional hardware or software design may be required. NXP Semiconductors does not support or warrant this information for any purpose other than an informational design example.