SLOA170B July   2012  – January 2021 DRV8242-Q1 , DRV8412 , DRV8424 , DRV8424E , DRV8425 , DRV8425E , DRV8426 , DRV8426E , DRV8428 , DRV8428E , DRV8434 , DRV8434E , DRV8436 , DRV8436E , DRV8701 , DRV8702-Q1 , DRV8702D-Q1 , DRV8703-Q1 , DRV8703D-Q1 , DRV8705-Q1 , DRV8706-Q1 , DRV8800 , DRV8801 , DRV8802 , DRV8802-Q1 , DRV8811 , DRV8812 , DRV8813 , DRV8814 , DRV8818 , DRV8821 , DRV8823 , DRV8823-Q1 , DRV8824 , DRV8824-Q1 , DRV8825 , DRV8828 , DRV8829 , DRV8832 , DRV8832-Q1 , DRV8833 , DRV8834 , DRV8840 , DRV8841 , DRV8842 , DRV8843 , DRV8844 , DRV8846 , DRV8848 , DRV8870 , DRV8874 , DRV8874-Q1 , DRV8876 , DRV8876-Q1 , DRV8880 , DRV8881 , DRV8885 , DRV8886 , DRV8889-Q1 , DRV8899-Q1 , DRV8935 , DRV8955

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 The Current Regulation Engine
    2. 1.2 Design Criteria
  3. 2Resistive Network Voltage Divider Method
    1. 2.1 GPIO Driven Voltage Divider
  4. 3Digital-to-Analog Converter Method
  5. 4PWM to RC Filter Method
  6. 5Changeable Holding Current Circuit
  7. 6Devices With Internal Reference Voltage
  8. 7Revision History

1.2 Design Criteria

Before selecting the external analog reference voltage, it is customary to select the SENSE resistor. Since the application will define the range of currents the power stage will be dealing with, a SENSE resistor must be selected so that the allowable reference voltage be in the permissible range as specified by the respective device’s datasheet.

The typical ITRIP equation is in the form of:

Equation 1. GUID-B7ECDAA2-914E-48EA-89DC-787863A1D2B4-low.gif

Where:

ITRIP is the current regulation set point
VREF is the analog reference voltage at the device’s VREF input.
AMP_GAIN is the internal amplifier gain
SENSER is the SENSE resistor in Ohms