SLVSB19D February 2012 – March 2015 DRV8834
PRODUCTION DATA.
- 1 Features
- 2 Applications
- 3 Description
- 4 Simplified Schematic
- 5 Revision History
- 6 Pin Configuration and Functions
- 7 Specifications
- 8 Detailed Description
- 9 Application and Implementation
- 10Power Supply Recommendations
- 11Layout
- 12Device and Documentation Support
- 13Mechanical, Packaging, and Orderable Information
封裝選項
機械數據 (封裝 | 引腳)
散熱焊盤機械數據 (封裝 | 引腳)
訂購信息
10 Power Supply Recommendations
10.1 Bulk Capacitance
Having appropriate local bulk capacitance is an important factor in motor drive system design. It is generally beneficial to have more bulk capacitance, while the disadvantages are increased cost and physical size.
The amount of local capacitance needed depends on a variety of factors, including:
- The highest current required by the motor system
- The capacitance of the power supply and its ability to source or sink current
- The amount of parasitic inductance between the power supply and motor system
- The acceptable voltage ripple
- The type of motor used (brushed DC, brushless DC, stepper)
- The motor braking method
The inductance between the power supply and motor drive system will limit the rate current can change from the power supply. If the local bulk capacitance is too small, the system will respond to excessive current demands or dumps from the motor with a change in voltage. When adequate bulk capacitance is used, the motor voltage remains stable and high current can be quickly supplied.
The data sheet generally provides a recommended value, but system-level testing is required to determine the appropriate sized bulk capacitor.
Figure 23. Example Setup of Motor Drive System With External Power Supply
The voltage rating for bulk capacitors should be higher than the operating voltage, to provide margin for cases when the motor transfers energy to the supply.