SLVSH04 November   2023 DRV8214

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Device Comparison
  7. 6 Pin Configuration and Functions
  8. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 I2C Timing Requirements
    7. 7.7 Timing Diagrams
    8. 7.8 Typical Operating Characteristics
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 External Components
      2. 8.3.2 Summary of Features
      3. 8.3.3 Bridge Control
      4. 8.3.4 Current Sense and Regulation (IPROPI)
        1. 8.3.4.1 Current Sensing and Current Mirror Gain Selection
        2. 8.3.4.2 Current Regulation
          1. 8.3.4.2.1 Fixed Off-Time Current Regulation
          2. 8.3.4.2.2 Cycle-By-Cycle Current Regulation
      5. 8.3.5 Stall Detection
      6. 8.3.6 Ripple Counting
        1. 8.3.6.1 Ripple Counting Parameters
          1. 8.3.6.1.1  Motor Resistance Inverse
          2. 8.3.6.1.2  Motor Resistance Inverse Scale
          3. 8.3.6.1.3  KMC Scaling Factor
          4. 8.3.6.1.4  KMC
          5. 8.3.6.1.5  Filter Damping Constant
          6. 8.3.6.1.6  Filter Input Scaling Factor
          7. 8.3.6.1.7  Ripple Count Threshold
          8. 8.3.6.1.8  Ripple Count Threshold Scale
          9. 8.3.6.1.9  T_MECH_FLT
          10. 8.3.6.1.10 VSNS_SEL
          11. 8.3.6.1.11 Error Correction
            1. 8.3.6.1.11.1 EC_FALSE_PER
            2. 8.3.6.1.11.2 EC_MISS_PER
        2. 8.3.6.2 RC_OUT Output
        3. 8.3.6.3 Ripple Counting with nFAULT
      7. 8.3.7 Motor Voltage and Speed Regulation
        1. 8.3.7.1 Internal Bridge Control
        2. 8.3.7.2 Setting Speed/Voltage Regulation Parameters
          1. 8.3.7.2.1 Speed and Voltage Set
          2. 8.3.7.2.2 Speed Scaling Factor
        3. 8.3.7.3 Soft-Start and Soft-Stop
          1. 8.3.7.3.1 TINRUSH
      8. 8.3.8 Protection Circuits
        1. 8.3.8.1 Overcurrent Protection (OCP)
        2. 8.3.8.2 Thermal Shutdown (TSD)
        3. 8.3.8.3 VCC Undervoltage Lockout (UVLO)
        4. 8.3.8.4 Overvoltage Protection (OVP)
        5. 8.3.8.5 nFAULT Output
    4. 8.4 Device Functional Modes
      1. 8.4.1 Active Mode
      2. 8.4.2 Low-Power Sleep Mode
      3. 8.4.3 Fault Mode
    5. 8.5 Programming
      1. 8.5.1 I2C Communication
        1. 8.5.1.1 I2C Write
        2. 8.5.1.2 I2C Read
    6. 8.6 Register Map
      1. 8.6.1 DRV8214_STATUS Registers
      2. 8.6.2 DRV8214_CONFIG Registers
      3. 8.6.3 DRV8214_CTRL Registers
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application: Brushed DC Motor
      1. 9.2.1 Design Requirements
      2. 9.2.2 Stall Detection
        1. 9.2.2.1 Application Description
          1. 9.2.2.1.1 Stall Detection Timing
          2. 9.2.2.1.2 Hardware Stall Threshold Selection
      3. 9.2.3 Ripple Counting Application
        1. 9.2.3.1 Tuning Ripple Counting Parameters
          1. 9.2.3.1.1 Resistance Parameters
          2. 9.2.3.1.2 KMC and KMC_SCALE
            1. 9.2.3.1.2.1 Case I
            2. 9.2.3.1.2.2 Case II
              1. 9.2.3.1.2.2.1 Method 1: Tuning from Scratch
                1. 9.2.3.1.2.2.1.1 Tuning KMC_SCALE
                2. 9.2.3.1.2.2.1.2 Tuning KMC
              2. 9.2.3.1.2.2.2 Method 2: Using the Proportionality factor
                1. 9.2.3.1.2.2.2.1 Working Example
          3. 9.2.3.1.3 Advanced Parameters
            1. 9.2.3.1.3.1 Filter Constants
              1. 9.2.3.1.3.1.1 FLT_GAIN_SEL
              2. 9.2.3.1.3.1.2 FLT_K
            2. 9.2.3.1.3.2 T_MECH_FLT
            3. 9.2.3.1.3.3 VSNS_SEL
            4. 9.2.3.1.3.4 Additional Error Corrector Parameters
              1. 9.2.3.1.3.4.1 EC_FALSE_PER
              2. 9.2.3.1.3.4.2 EC_MISS_PER
      4. 9.2.4 Motor Voltage
      5. 9.2.5 Motor Current
      6. 9.2.6 Application Curves
  11. 10Power Supply Recommendations
    1. 10.1 Bulk Capacitance
  12. 11Layout
    1. 11.1 Layout Guidelines
  13. 12Mechanical, Packaging, and Orderable Information
    1. 12.1 Tape and Reel Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information
8.3.6.1.3 KMC Scaling Factor

Denoted by KMC_SCALE, this is a scaling factor for the parameter KMC. KMC is represented by the following equation:

Equation 5. K M C =   K V N R × K M C _ S C A L E

Where, KV is the motor back emf constant and NR is the number of ripples per revolution. NR is calculated by taking the LCM (Least Common Multiple) of the number of brushes, NB, and the number of commutators, NC:

Equation 6. N R = L C M N B , N C

Please note that LCM can be easily calculated by using any online LCM calculator.

Tuning KMC appropriately is critical for the ripple counting algorithm to perform accurately. Scaling is done because the value of motor back emf constant is generally small. Scaling allows integer values to be written on to registers.

Table 8-14 Settings for KMC_SCALE
Bit Value of KMC_SCALE
00b 24 x 28
01b 24 x 29
10b 24 x 212
11b 24 x 213