ZHCSIQ7A august 2018 – december 2021 UCC28951
PRODUCTION DATA
- 1 特性
- 2 应用
- 3 说明
- 4 Revision History
- 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 Start-Up Protection Logic
- 7.3.2 Voltage Reference (VREF)
- 7.3.3 Error Amplifier (EA+, EA–, COMP)
- 7.3.4 Soft-Start and Enable (SS/EN)
- 7.3.5 Light-Load Power Saving Features
- 7.3.6 Adaptive Delay, (Delay Between OUTA and OUTB, OUTC and OUTD (DELAB, DELCD, ADEL))
- 7.3.7 Adaptive Delay (Delay Between OUTA and OUTF, OUTB and OUTE (DELEF, ADELEF)
- 7.3.8 Minimum Pulse (TMIN)
- 7.3.9 Burst Mode
- 7.3.10 Switching Frequency Setting
- 7.3.11 Slope Compensation (RSUM)
- 7.3.12 Dynamic SR ON/OFF Control (DCM Mode)
- 7.3.13 Current Sensing (CS)
- 7.3.14 Cycle-by-Cycle Current Limit Current Protection and Hiccup Mode
- 7.3.15 Synchronization (SYNC)
- 7.3.16 Outputs (OUTA, OUTB, OUTC, OUTD, OUTE, OUTF)
- 7.3.17 Supply Voltage (VDD)
- 7.3.18 Ground (GND)
- 7.4 Device Functional Modes
-
8 Application 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 Power Loss Budget
- 8.2.2.2 Preliminary Transformer Calculations (T1)
- 8.2.2.3 QA, QB, QC, QD FET Selection
- 8.2.2.4 Selecting LS
- 8.2.2.5 Selecting Diodes DB and DC
- 8.2.2.6 Output Inductor Selection (LOUT)
- 8.2.2.7 Output Capacitance (COUT)
- 8.2.2.8 Select FETs QE and QF
- 8.2.2.9 Input Capacitance (CIN)
- 8.2.2.10 Current Sense Network (CT, RCS, R7, DA)
- 8.2.3 Application Curves
- 9 Power Supply Recommendations
- 10Layout
- 11Device and Documentation Support
6.8 Typical Characteristics
Figure 6-3 UVLO Thresholds vs Temperature
Figure 6-5 Supply Current vs Temperature
Figure 6-7 Voltage Reference (VDD = 12 V) vs Temperature
Figure 6-9 Short-Circuit Current vs Temperature
Figure 6-11 Nominal Switching Frequency vs Temperature
Figure 6-13 Error Amplifier Offset Voltage vs Temperature
Figure 6-15 ISS Charge Current vs Temperature
Figure 6-17 SS Pullup Threshold vs Temperature
Figure 6-19 Current Sense Cycle-by-Cycle Limit vs Temperature
Figure 6-21 Outputs Sink Resistance vs Temperature
Figure 6-23 Outputs Source Resistance vs Temperature
Figure 6-25 Dead Time Delay vs Temperature
Figure 6-27 DCM Threshold vs Temperature
Figure 6-4 UVLO Hysteresis vs Temperature
Figure 6-6 Start-Up Current vs Temperature
Figure 6-8 Line Voltage Regulation (ILOAD = 10 mA) vs Temperature
Figure 6-10 Maximum Duty Cycle vs Temperature
Figure 6-12 Maximum Switching Frequency vs Temperature
Figure 6-14 Voltage Error Amplifier (Open-Loop Gain) vs Temperature
Figure 6-16 Shutdown, Restart, and Reset Threshold vs Temperature
Figure 6-18 SS Clamp Voltage vs Temperature
Figure 6-20 Current Sense Propagation Delay vs Temperature
Figure 6-22 Outputs Sink Resistance vs Temperature
Figure 6-24 Outputs Source Resistance vs Temperature
Figure 6-26 Dead Time Delay vs Temperature