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21 Qorvo 2021 The Sophisticated Power Tool Modern power tools still consist of a power source, a motor actuator, and a means to control energy flow, such as a potentiometer. However, to provide all the energy preservation, we need to add intelligence. A microprocessor provides intelligence. With a microprocessor, we can now monitor the power source and provide the required actuation. We can also monitor the value of the potentiometer and control the motor speed without having to pass the current through its resistive component. We achieve this by using Analog to Digital Converters (ADC). The energy expenditure in this action is negligible. However, the most important aspect of the microprocessor is to provide an efficient mechanism to properly energize tri-phase BLDC motors to obtain the efficiency improvements that battery-powered tools require. The microcontroller- based power stage provides all the tools to generate a properly aligned revolving magnetic field, which translates into the best possible motion profile. The PAC5527 contains a DC/DC converter that takes the battery voltage and steps it down to the different rails required to power the system's different blocks. Three high- current pre-driver stages required to drive a very powerful tri-phase inverter (over 1kW) are included. Its ADC, with a programmable sequencer, allows for the coordinated capture of multiple analog parameters without affecting the central processing unit's (CPU's) real-time. It encompasses protection blocks to ensure the system current is kept within bounds, protecting against hazardous conditions that can induce tool damage while at the same time removing the user from harm's way, such as a fire. Multiple general- purpose input/outputs (GPIOs) to monitor different signals are provided. Even the circuitry to extract rotor position allows us to generate a fully aligned revolving magnetic field, which forms part of the arsenal of tools encased within a single PAC5527 device. The PAC5527 generates one of the smallest possible tri- phase inverter power drivers. They're so small, power tools revolving around this solution can be shaped to be ergonomically efficient while enhancing the power tool's energy efficiency. Additionally, because of its small footprint and high level of integration, the entire application's cost structure is also optimized. The Next Wave of Power Tools The use of BLDC motor manufacturing is revving up, and as technology continues to evolve, these motors will become even more user-friendly, effective, and reliable. Because of the onset of electronically controlled BLDC motors, tools are more powerful, more efficient, smaller in size, and lighter in weight. With each passing year, Qorvo will continue to provide innovative products such as the PAC5xxx series of parts to further propel tri-phase BLDC motor topology. Figure 3: BLDC motors do not have a physical commutator and must use commutation logic sequencing. To obtain efficiencies, both magnetic fields must be aligned as perfectly as possible using a control circuit. (Source: Qorvo).