Use ihm08m1 to generate 3 independent PWM

[richard orengo]

Hi. I would like to know if it is possible to use Ihm08m1 to drive bldc with 3 independent Pwm...to not use complementary channels ? If so, is there an example how to drive l6398 correctly ?​

[Cristiana SCARAMEL]

Hello @richard orengo​,

if I understand well you want to use only three PWM (one for each driver) and connect together LIN and HIN, right?

Theoretically you can do it, but you should physically create the hardware connection between the input signals of each driver (no solder option is available)

Referring to X-NUCLEO-IHM08M1 schematic the L6398 driving signals are mapped on the morpho connectors CN7 & CN10.

However the X-NUCLEO-IHM08M1 expansion board was designed to be used together with STM32 Nucleo board and then exploit the Advanced-control timer function (TIM1) of STM32 MCU. TIM1 can be seen as a three-phase PWM multiplexed on six channels. It has complementary PWM outputs with programmable inserted deadtimes and it is is used to generate the PWM signal for the three half-bridge gate drivers.

You can find more details on how to drive the X-NUCLEO-IHM08M1 expansion board with our STM32 Nucleo board in the user manual UM1996.

Moreover, an example of 6-step control is in the X-CUBE-SPN8 expansion software package or in the ST Motor Control Workbench X-CUBE-MCSDK (FOC and 6-step examples).

Please, share more details about your application:

• Which control board are you going to use?
• What driving method would you like to implement (FOC or 6-step)?

Let me know if this info is useful for your purpose.

[Cristiana SCARAMEL]

Hello @richard orengo​,

any feedback from you?