SLVAFG1 September   2022 DRV8329

 

  1.   Abstract
  2.   Trademarks
  3. 1DRV8329 Key Features
  4. 2Power Tool Requirements
    1. 2.1 Performance
    2. 2.2 Robustness
    3. 2.3 Scalability
      1. 2.3.1 Battery Pack Quality
      2. 2.3.2 Battery Pack Voltage
  5. 3Summary

Battery Pack Voltage

Power tool batteries can range from 4VDC to 60VDC. During operation, instantaneous changes in motor current can cause transients up to 2x the battery's nominal voltage rating. It is beneficial to select a motor driver than can support these transients while also providing a wide input voltage range so the driver and power stage design can be re-used across multiple platforms for simplicity and lowering BOM cost. For instance, a power tool platform can be scaled up to 24-V in well-designed systems for a motor driver with a 60-V absolute maximum rating.

Figure 2-3 Battery Packs With Varying Voltage and Quality for Power Tool Applications

The DRV8329 is an ideal Brushless-DC gate driver to scale across power tool platforms. With a wide recommended operating range of 4.5-V to 60-V, it can support 2S to 10S power tools with at least 10 volts of gate-to-source voltage to switch power MOSFETs during power tool operation. With low input supply voltages, the integrated charge pump in the DRV8329 automatically scales the supply voltage to a sufficient gate drive voltage to continue driving the FETs. An example application is when power tools apply high amounts of torque, which causes the motor to stall and supply voltages to drop down due to stall current conducting through the battery impedance. This is ideal for low-cost power tool applications that use Tier 2 battery suppliers, operate a low voltage ranges, have smaller supply bulk capacitance, or require smaller form factors.

Figure 2-4 DRV8329 GVDD Voltage Over PVDD Voltage