SLVSCP9 August   2014 DRV8833C

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 Handling Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 PWM Motor Drivers
      2. 7.3.2 Bridge Control and Decay Modes
      3. 7.3.3 Current Control
      4. 7.3.4 Decay Mode
      5. 7.3.5 Slow Decay
      6. 7.3.6 Sleep Mode
      7. 7.3.7 Parallel Mode
      8. 7.3.8 Protection Circuits
        1. 7.3.8.1 Overcurrent Protection (OCP)
        2. 7.3.8.2 Thermal Shutdown (TSD)
        3. 7.3.8.3 UVLO
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Stepper Motor Speed
        2. 8.2.2.2 Current Regulation
      3. 8.2.3 Application Curve
  9. 9 Power Supply Recommendations
    1. 9.1 Sizing Bulk Capacitance for Motor Drive Systems
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Trademarks
    2. 11.2 Electrostatic Discharge Caution
    3. 11.3 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

8 Application and Implementation

8.1 Application Information

The DRV8833C is used in stepper or brushed DC motor control. The following design procedure can be used to configure the DRV8833C in a bipolar stepper motor application.

8.2 Typical Application

typ_app_LVSCP9.gif

8.2.1 Design Requirements

Table 5 gives design input parameters for system design.

Table 5. Design Parameters

Design Parameter Reference Example Value
Supply voltage VM 9 V
Motor winding resistance RL 12 Ω/phase
Motor winding inductance LL 10 mH/phase
Motor full step angle θstep 1.8 °/step
Target stepping level nm 2 (half-stepping)
Target motor speed v 120 rpm
Target chopping current ICHOP 200 mA
Sense resistor RISEN 1 Ω

8.2.2 Detailed Design Procedure

8.2.2.1 Stepper Motor Speed

The first step in configuring the DRV8833C requires the desired motor speed and stepping level. The DRV8833C can support full- and half-stepping modes using the PWM interface.

If the target motor speed is too high, the motor does not spin. Ensure that the motor can support the target speed.

For a desired motor speed (v), microstepping level (nm), and motor full step angle (θstep),

Equation 2. eq_f_step_LVSCP9.gif
tim_full-step_LVSCP9.gifFigure 10. Full-Step Mode
tim_half-step_LVSCP9.gifFigure 11. Half-Step Mode

8.2.2.2 Current Regulation

The chopping current (ICHOP) is the maximum current driven through either winding. This quantity depends on the sense resistor value (RXISEN).

Equation 3. eq_I_chop_LVSCP9.gif

ICHOP is set by a comparator which compares the voltage across RXISEN to a reference voltage. Note that ICHOP must follow Equation 4 to avoid saturating the motor.

Equation 4. eq_I_fs_LVSCP9.gif

where

  • VM is the motor supply voltage.
  • RL is the motor winding resistance.

8.2.3 Application Curve

app_curve_1_LVSCP9.gif
A. Channel 1 is the AIN1 input PWM signal, and channel 2 is the AIN2 input PWM signal. BIN1 and BIN2 follow the same pattern, but are shifted by 90° from AIN1 and AIN2 as shown in Figure 11. Channel 4 is the output current in the direction AOUT1 → AOUT2. In forward and reverse drive, the current rises until it hits the current chopping limit of 200 mA, and is regulated at that level with fixed-off time current chopping.
Figure 12. ½ Stepping Operation