SLVSCF7B February   2014  – November 2017 DRV8308


  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configurations and Functions
  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 SPI Timing Requirements
    7. 6.7 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Hall Comparators
      2. 7.3.2  FG Amplifier, Comparator, and FG Output
      3. 7.3.3  Enable, Reset, and Clock Generation
      4. 7.3.4  Commutation
        1. 120° 3-Hall Commutation
        2. 120° Single-Hall Commutation
        3. 180° Sine-Wave-Drive Commutation
      5. 7.3.5  Commutation Logic Block Diagram
      6. 7.3.6  Commutation Parameters
      7. 7.3.7  Braking
      8. 7.3.8  Output Pre-Drivers
      9. 7.3.9  Current Limit
      10. 7.3.10 Charge Pump
      11. 7.3.11 5-V Linear Regulator
      12. 7.3.12 Power Switch
      13. 7.3.13 Protection Circuits
        1. VM Undervoltage Lockout (UVLO)
        2. VM Overvoltage (VMOV)
        3. Motor Overcurrent (OCP)
        4. Charge Pump Failure (CPFAIL)
        5. Charge Pump Short (CPSC)
        6. Overtemperature (OTS)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Modes of Speed Input
        1. Clock Frequency Mode
        2. Clock PWM and Internal Register PWM Modes
      2. 7.4.2 Auto Gain and Advance Compensation
      3. 7.4.3 External EEPROM Mode
    5. 7.5 Programming
      1. 7.5.1 Serial Interface
      2. 7.5.2 Serial Data Format
      3. 7.5.3 Programming the OTP Configuration Memory
    6. 7.6 Register Map
      1. 7.6.1 Control Registers
  8. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Internal Speed Control Loop Constraints
      2. 8.1.2 Hall Sensor Configurations and Connections
      3. 8.1.3 FG Amplifier Configurations and Connections
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. Motor voltage
        2. Motor Current (Peak and RMS)
        3. Speed Command Method
        4. Required Flutter (Speed Jitter)
        5. Configuration Method
        6. Hall Element Current
        7. Power FET Switching Time
      3. 8.2.3 Application Curves
    3. 8.3 Do's and Don'ts
      1. 8.3.1 RESET and ENABLE Considerations
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Pin Configurations and Functions

RHA Package
40-Pin VQFN With Exposed Thermal Pad
Top View
DRV8308 po_SLVSCF7.gif

Pin Functions

CP1 30 PWR Charge pump flying capacitor Connect a 0.1-μF 35-V capacitor between CP1 and CP2
CP2 29 PWR
GND 26, PPAD PWR Ground reference. Pin 26 and the exposed thermal pad are internally connected. Connect to board GND
VCP 28 PWR Charge pump storage capacitor Connect a 1-μF 35-V ceramic capacitor to VM
VINT 25 PWR Internal 1.8-V core voltage regulator bypass Bypass to GND with a 1-μF 6.3-V ceramic capacitor
VM 27 PWR Motor supply voltage Connect to motor supply voltage.
Bypass to GND with a 0.1-μF ceramic capacitor, plus a large electrolytic capacitor (47 μF or larger is recommended), with a voltage rating of 1.5× to 2.5× VM.
VREG 24 PWR 5-V regulator output. Active when ENABLE is active. Bypass to GND with a 0.1-μF 10-V ceramic capacitor. Can provide 5-V power to Hall sensors.
VSW 7 PWR Switched VM power output. When ENABLE is active, VM is applied to this pin. Can be used for powering Hall elements, along with added series resistance.
BRAKE 20 I Causes motor to brake. Polarity is programmable. Internal pulldown resistor.
CLKIN 19 I The clock input, used in Clock Frequency Mode and Clock PWM Mode. Internal pulldown resistor.
DIR 21 I Sets motor rotation direction. Polarity is programmable. Internal pulldown resistor.
ENABLE 22 I Enables and disables motor. Polarity is programmable. Internal pulldown resistor.
FAULTn 17 OD Fault indicator – active low when overcurrent, or overtemperature. Open-drain output.
FGOUT 16 OD Outputs a TACH signal generated from the FG amplifier or Hall sensors. Open-drain output.
LOCKn 18 OD Outputs a signal that indicates the speed loop is locked. Open-drain output.
RESET 23 I Active high to reset all internal logic. Internal pulldown resistor.
SCLK(2) 11 I/OD Serial clock SPI mode: Serial clock input. Data is clocked on rising edges. Internal pulldown resistor.
EEPROM mode: Connect to EEPROM CLK. Open-drain output requires external pullup.
SCS(2) 12 I/OD Serial chip select SPI mode: Active high enables serial interface operation. Internal pulldown resistor.
EEPROM mode: Connect to EEPROM CS. Open-drain output requires external pullup.
SDATAI 14 I Serial data input SPI mode: Serial data input. Internal pulldown resistor.
EEPROM mode: Serial data input. Connect to EEPROM DO terminal.
SDATAO 15 OD Serial data output SPI mode: Serial data output. Open-drain output.
EEPROM mode: Connect to EEPROM DI. Open-drain output requires external pullup.
SMODE 13 I Serial mode SPI mode: leave open or connect to ground for SPI interface mode.
EEPROM mode: Connect to logic high to for EEPROM mode.
ISEN 31 I Low-side current sense resistor Connect to low-side current sense resistor
U 33 I Measures motor phase voltages for VFETOCP Connect to motor windings
V 36 I
W 39 I
UHSG 32 O High-side FET gate outputs Connect to high-side 1/2-H N-channel FET gate
ULSG 34 O Low-side FET gate outputs Connect to low-side 1/2-H N-channel FET gate
FGFB 8 O FG amplifier feedback pin Connect feedback network to FGIN–
FGINN_TACH 9 I(3) FG amplifier negative input or TACH input Connect to FG trace and filter components. When using a TACH with FGSEL= 3, connect a logic-level TACH signal. If unused, connect FGFB to FG–.
FGINP 10 I/O FG amplifier positive input Connect to FG trace and filter components on the PCB (if used).
UHP 1 I Hall sensor U positive input Connect to Hall sensors. Noise filter capacitors may be desirable, connected between the + and – Hall inputs.
UHN 2 I Hall sensor U negative input
VHP 3 I Hall sensor V positive input
VHN 4 I Hall sensor V negative input
WHP 5 I Hall sensor W positive input
WHN 6 I Hall sensor W negative input
I = input, O = output, OD = open-drain output, I/O = input/output
In SPI mode, these pins are inputs; in EEPROM mode, they are open-drain outputs.
When using FG amplifier, this pin is an analog input. If in TACH mode, this is a logic-level input.