ZHCSOE5C March 2022 – June 2024 UCC21737-Q1
PRODUCTION DATA
- 1
- 1 特性
- 2 應用
- 3 說明
- 4 Pin Configuration and Functions
-
5 Specifications
- 5.1 Absolute Maximum Ratings
- 5.2 ESD Ratings
- 5.3 Recommended Operating Conditions
- 5.4 Thermal Information
- 5.5 Power Ratings
- 5.6 Insulation Specifications
- 5.7 Safety Limiting Values
- 5.8 Electrical Characteristics
- 5.9 Switching Characteristics
- 5.10 Insulation Characteristics Curves
- 5.11 Typical Characteristics
- 6 Parameter Measurement Information
-
7 Detailed Description
- 7.1 Overview
- 7.2 Functional Block Diagram
- 7.3
Feature Description
- 7.3.1 Power Supply
- 7.3.2 Driver Stage
- 7.3.3 VCC and VDD and VEE Undervoltage Lockout (UVLO)
- 7.3.4 Active Pulldown
- 7.3.5 Short Circuit Clamping
- 7.3.6 External Active Miller Clamp
- 7.3.7 Overcurrent and Short Circuit Protection
- 7.3.8 Soft Turn-off
- 7.3.9 Fault (FLT), Reset, and Enable (RST/EN)
- 7.3.10 ASC Support and APWM Monitor
- 7.4 Device Functional Modes
-
8 Applications and Implementation
- 8.1 Application Information
- 8.2
Typical Application
- 8.2.1 Design Requirements
- 8.2.2
Detailed Design Procedure
- 8.2.2.1 Input Filters for IN+, IN-, and RST/EN
- 8.2.2.2 PWM Interlock of IN+ and IN-
- 8.2.2.3 FLT, RDY, and RST/EN Pin Circuitry
- 8.2.2.4 RST/EN Pin Control
- 8.2.2.5 Turn-On and Turn-Off Gate Resistors
- 8.2.2.6 External Active Miller Clamp
- 8.2.2.7 Overcurrent and Short Circuit Protection
- 8.2.2.8 Higher Output Current Using an External Current Buffer
- 8.2.3 Application Curves
- 9 Power Supply Recommendations
- 10Layout
- 11Device and Documentation Support
- 12Revision History
- 13Mechanical, Packaging, and Orderable Information
8.2.2.7.3 Protection Based on Shunt Resistor in Power Loop
In lower power applications, to simplify the circuit and reduce cost, a shunt resistor can be used in series in the power loop and measure the current directly. Since the resistor is in series in the power loop, it directly measures the current and can have high accuracy by using a high precision resistor. The resistance needs to be small to reduce the power loss, and should have large enough voltage resolution for the protection. Since the sensing resistor is also in series in the gate driver loop, the voltage drop on the sensing resistor can cause the voltage drop on the gate voltage of the IGBT or SiC MOSFET modules. The parasitic inductance of the sensing resistor and the PCB trace of the sensing loop cause a noise voltage source during switching transient, which makes the gate voltage oscillate. Thus, this method is not recommended for a high power application, or when dI/dt is high. To use it in low power application, the shunt resistor loop should be designed to have the optimal voltage drop and minimum noise injection to the gate loop.
Figure 8-10 Overcurrent and Short Circuit
Protection Based on Shunt Resistor