Research And Design Of Wide Power Supply H-Bridge DC Stepper Motor Driver Chip

The innovative development of electronic technology,so that the intelligent power motor with low cost,small size,safety and reliability and many other advantages to become the core components of modern electronic products,playing an irreplaceable role,especially in the emerging high-end electronic consumer market,electronic products are intelligent power motor function,power and control precision and other aspects of the new higher requirements,so the motor drive chip Therefore,it is important to conduct in-depth research on motor drive chips.Based on the 0.35 μm 60 V BCD process of Nuvoton Technology,a high-voltage DC motor driver chip is designed in this project.The chip contains a high-voltage LDO power supply circuit,RC oscillator circuit,H-bridge high-side MOS gate drive circuit,charge pump circuit,and over-temperature and over-current protection circuit.The chip has an input voltage range of 10～60 V,an internal H-bridge power device with an on-state resistance of 300 mΩ,and a maximum output current value of 3 A during stable operation.Firstly,in this thesis,the self-start circuit that the output follows the rising power supply is used in the chip power module design.When the output voltage of the bandgap circuit is 1.2 V,the self-start circuit turns off to ensure that the LDO output voltage of 5 V is stable,and the circuit design is simulated at high and low temperatures and different process angles to improve the reliability of the power module.Secondly,the RC frequency selective oscillator circuit designed in this paper innovatively designs RC value selective switch groups,which can be composed of various frequency groups by external digital signals to provide precise 100 KHz frequency inside the chip,which has a wider application scenario and higher accuracy compared with traditional oscillators.Finally,the power tube drive circuit designed in this paper provides innovative design for fast charging and discharging of the power tube gate to speed up the power tube gate power-up and reduce the impact of the power tube Miller platform on the chip.Cadence software is applied to systematically simulate and verify the circuit designed in this paper,and complete the layout design.The overall joint simulation of the motor drive chip shows that the quiescent current is 900 μA during the no-switch operation,the sleep mode power consumption is only 0.015 W at 60 V input voltage,and the chip output current is 3 A at 60 V.Moreover,the chip can realize various functions such as driving the motor forward and reverse rotation,motor fast and slow decay control and sleep mode by changing the input control signal.Finally,the samples were tested for practical application,and the results show that the motor driver chip designed in this paper drives a small power DC motor to run normally and the main parameters meet the design requirements.