ZHCSKB9Q December 1999 – October 2019 UCC1895 , UCC2895 , UCC3895
PRODUCTION DATA.
- 1 特性
- 2 應用
- 3 說明
- 4 修訂歷史記錄
- 5 Pin Configuration and Functions
- 6 Specifications
-
7 Detailed Description
- 7.1 Overview
- 7.2 Functional Block Diagrams
- 7.3
Feature Description
- 7.3.1 ADS (Adaptive Delay Set)
- 7.3.2 CS (Current Sense)
- 7.3.3 CT (Oscillator Timing Capacitor)
- 7.3.4 DELAB and DELCD (Delay Programming Between Complementary Outputs)
- 7.3.5 EAOUT, EAP, and EAN (Error Amplifier)
- 7.3.6 OUTA, OUTB, OUTC, and OUTD (Output MOSFET Drivers)
- 7.3.7 PGND (Power Ground)
- 7.3.8 RAMP (Inverting Input of the PWM Comparator)
- 7.3.9 REF (Voltage Reference)
- 7.3.10 RT (Oscillator Timing Resistor)
- 7.3.11 GND (Analog Ground)
- 7.3.12 SS/DISB (Soft Start/Disable)
- 7.3.13 SYNC (Oscillator Synchronization)
- 7.3.14 VDD (Chip Supply)
- 7.4 Device Functional Modes
- 7.5 Programming
-
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 Rectifier Diodes
- 8.2.2.9 Input Capacitance (CIN)
- 8.2.2.10 Current Sense Network (CT, RCS, RR, DA)
- 8.2.3 Application Curves
- 9 Power Supply Recommendations
- 10Layout
- 11器件和文檔支持
- 12機械、封裝和可訂購信息
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
8.2.2.10.4 Soft Start
Equation 110. 
The UCC3895 has a soft-start function to reduce component stresses during the start-up phase. For this design we set the soft-start time to 50 ms. This time is controlled by the value of the capacitor CSS at the SS/DISB pin and the charging current set by RT (Equation 4).
Equation 111. 