Issue link: https://resources.mouser.com/i/1442844
31 Qorvo 2021 The motor control functions provided by the Qorvo chip also support many protective measures, such as: Overvoltage, undervoltage, and overcurrent detection and regulation Internal power supply monitoring and protection Locked rotor protection Open circuit protection Over-temperature shutdown and reset of the MCU when required From a design standpoint, without the computational capabilities available through the Qorvo chip, the challenges of controlling and protecting the power system in the vacuum would require substantial additional design work and many extra components. With the Qorvo SoC integrated into the product, a constant motor speed of 120,000rpms can be sustained through varying conditions. The chip provides everything required to drive the vacuum motor and maximize its efficiency. Ensuring Quick Startup Speed The motor-starting algorithm needs information about the rotor position to ensure a smooth, quick startup for the vacuum. To accomplish this, Qorvo used its SoC to deliver a high-frequency signal to the motor to capture data on the inductance of the three-phase motor. The starting algorithm used this data to calculate rotor position. In past-generation brushless motor designs, expensive, failure-prone Hall Sensors were used to detect rotor position. But in this design, the built-in capabilities of the Qorvo SoC can handle this task without needing any additional Hall sensor components. The information about the rotor position makes it possible to avoid reverse rotation during startup and contributes to enabling a fast start speed within approximately 5 seconds. Figure 2: Key components in the motor drive circuit. (Source: Qorvo). Providing a Cost-Effective Design Consolidating all the logic and circuitry for performing motor control functions into a single Qorvo PAC motor control chip is the key to the cost-effective design of this product. By avoiding using discrete components in the design, the maintenance requirements are minimized, and the product lifecycle is extended. The highly integrated SoC, providing the power supply, gate drives, analog front end, an economical embedded processor from ARM, and other parts, leads to lower bill-of-material (BOM) costs. The sophisticated algorithm devised by Qorvo enables numerous motor control functions to be carried out through the available SoC hardware. For example, the design features sensorless FOC control based on a single-resistor sampling method, rather than requiring three sampling resistors as in many past-generation designs. Figure 2 shows the circuit that performs these operations. The custom algorithm also enables power conservation and efficiency features in the design, lowering overall power consumption while delivering impressive performance under an extended range of conditions. Power consumption during sleep mode, controlled by the Qorvo PAC, is 12 microamps, and standby power requirements for the vacuum are also very low. As with this design, Qorvo works closely with customers to develop solutions that extend the boundaries of existing technologies, working collaboratively to design products that balance performance, efficiency, and cost. PAC5225 Power Application Controllers ® LEARN MORE >