Full-bridge module for high-power brushed motor drive/inverter (updated SPWM code)

PCB photo:

Physical map:

characteristic

• There is no PWM generator, and an external microcontroller or 3525 control circuit is required.

• The built-in 12v300ma voltage reducer provides the voltage for the driving part and control circuit.

• There are four logic control pins, all of which are positive logic and support 3.3v/5v level.

• PWM is recommended not to exceed 90% and 200KHz.

• Wide voltage input range 10-36V, built-in undervoltage protection, the power input voltage can reach up to 50V when the driver part is independently powered (the filter capacitor needs to be replaced).

• The chip has a built-in dead time generator, and the Mos tube is connected in parallel with the Schottky diode for freewheeling. It effectively protects the H-bridge when carrying inductive loads and frequently commutates, avoiding direct damage and making software programming easier.

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Welding and usage instructions:

• The four terminals H1L1H2LL2 are used to connect to the MCU and control the full-bridge mos tube.

• The VCC terminal is the output of the onboard voltage reducer and can carry a 12v fan with a current of no more than 200ma.

• The Vin terminal is the input of the onboard voltage reducer. When disconnecting R12, you need to input 15-40v voltage here.

• Vpower is the main power input, the full bridge will modulate the voltage input here

• R12 is the selection jumper for the voltage regulator input, short circuit to take power from Vpower

• Adjusting the ratio of R10 and R11 can adjust the output voltage of the buck, but it is not recommended to be lower than 10v or higher than 15v. The default is 12v.

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Bipolar modulation SPWM example based on STM32F0: See the attachment spwm_test1.7z for the code

• In hardware, short-circuit L1 and H2, short-circuit L2 and H1, because bipolar modulation only requires one complementary PWM, and the tubes on the diagonal are driven by the same logic.

STM32 uses two timers, TIM1 uses CH3 to complementary output 48K PWM as the carrier, TIM17 serves as the interrupt time base, and the interrupt frequency is 12.8khz (fundamental wave 50Hz X modulation ratio 256). Use the equal area method to calculate the SPWM duty cycle sequence, rewrite the TIM17 interrupt callback function, update the value of TIM1->CCR3 for each interrupt, and dynamically change the duty cycle. The output is SPWM, and after filtering it is a sine wave. Waveform diagrams and physical pictures: //STM32 ESC control code is being written and will be uploaded at a later date.