ZHCSN08D August 2020 – April 2024 DRV8714-Q1 , DRV8718-Q1
PRODMIX
- 1
- 1 特性
- 2 應用
- 3 說明
- 4 Device Comparison Table
- 5 Pin Configuration and Functions
- 6 Specifications
-
7 Detailed Description
- 7.1 Overview
- 7.2 Functional Block Diagram
- 7.3
Feature Description
- 7.3.1 External Components
- 7.3.2 Device Interface Variants
- 7.3.3 Input PWM Control Modes
- 7.3.4 Smart Gate Driver
- 7.3.5 Tripler (Dual-Stage) Charge Pump
- 7.3.6 Wide Common-Mode Current Shunt Amplifiers
- 7.3.7 Pin Diagrams
- 7.3.8
Protection and Diagnostics
- 7.3.8.1 Gate Driver Disable (DRVOFF/nFLT and EN_DRV)
- 7.3.8.2 Low IQ Powered Off Braking (POB, BRAKE)
- 7.3.8.3 Fault Reset (CLR_FLT)
- 7.3.8.4 DVDD Logic Supply Power on Reset (DVDD_POR)
- 7.3.8.5 PVDD Supply Undervoltage Monitor (PVDD_UV)
- 7.3.8.6 PVDD Supply Overvoltage Monitor (PVDD_OV)
- 7.3.8.7 VCP Charge Pump Undervoltage Lockout (VCP_UV)
- 7.3.8.8 MOSFET VDS Overcurrent Protection (VDS_OCP)
- 7.3.8.9 Gate Driver Fault (VGS_GDF)
- 7.3.8.10 Thermal Warning (OTW)
- 7.3.8.11 Thermal Shutdown (OTSD)
- 7.3.8.12 Offline Short Circuit and Open Load Detection (OOL and OSC)
- 7.3.8.13 Watchdog Timer
- 7.3.8.14 Fault Detection and Response Summary Table
- 7.4 Device Functional Modes
- 7.5 Programming
- 8 Register Maps
- 9 Application Implementation
- 10Device Documentation and Support
- 11Revision History
- 12Mechanical, 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
7.3.4.4.3 Detecting Drive and Freewheel MOSFET
By default, the PDR loop automatically detects which MOSFET is the drive MOSFET and which MOSFET is the freewheel MOSFET by determining the polarity of the current out of the half-bridge. This is done by measuring the half-bridge VSHx voltage during the dead-time period to determine if the high-side or low-side body diode is conducting. If the current polarity cannot be determined it is assumed that the configured MOSFET through PWMx_HL is the drive MOSFET. The automatic freewheel detection can be disabled with the IDIR_MAN_x control register. In the manual freewheel modes, the PDR loop relies on the PWMx_HL control register to determine which MOSFET is the drive MOSFET and which MOSFET is the freewheel MOSFET. IF PWMx_HL = 0b, the high-side MOSFET is the drive MOSFET and the low-side MOSFET is the freewheel MOSFET. If PWMx_HL = 1b, the low-side MOSFET is the drive MOSFET and high-side MOSFET is the freewheel MOSFET.
Figure 7-15 shows the high-side MOSFET (HS1) controlling the VSHx switch-node voltage transition and the low-side MOSFET (LS1) acting as the freewheeling MOSFET.
Figure 7-15 HS Drive PWM Turn On / Off
ExampleFigure 7-16 shows the low-side MOSFET (LS2) controlling the VSHx switch-node voltage transition and the high-side MOSFET (HS2) acting as the freewheeling MOSFET.
Figure 7-16 LS Drive PWM Turn On / Off
Example