ZHCSLD2E may 2020 – july 2023 UCC28782
PRODUCTION DATA
- 1
- 1 特性
- 2 應(yīng)用
- 3 描述
- 4 Revision History
- 5 Device Comparison Table
- 6 Pin Configuration and Functions
- 7 Specifications
-
8 Detailed Description
- 8.1 Overview
- 8.2 Functional Block Diagram
- 8.3
Detailed Pin Description
- 8.3.1 BUR Pin (Programmable Burst Mode)
- 8.3.2 FB Pin (Feedback Pin)
- 8.3.3 REF Pin (Internal 5-V Bias)
- 8.3.4 VDD Pin (Device Bias Supply)
- 8.3.5 P13 and SWS Pins
- 8.3.6 S13 Pin
- 8.3.7 IPC Pin (Intelligent Power Control Pin)
- 8.3.8 RUN Pin (Driver and Bias Source for Isolator)
- 8.3.9 PWMH and AGND Pins
- 8.3.10 PWML and PGND Pins
- 8.3.11 SET Pin
- 8.3.12 RTZ Pin (Sets Delay for Transition Time to Zero)
- 8.3.13 RDM Pin (Sets Synthesized Demagnetization Time for ZVS Tuning)
- 8.3.14 BIN, BSW, and BGND Pins
- 8.3.15 XCD Pin
- 8.3.16 CS, VS, and FLT Pins
- 8.4
Device Functional Modes
- 8.4.1 Adaptive ZVS Control with Auto-Tuning
- 8.4.2 Dead-Time Optimization
- 8.4.3 EMI Dither and Dither Fading Function
- 8.4.4 Control Law across Entire Load Range
- 8.4.5 Adaptive Amplitude Modulation (AAM)
- 8.4.6 Adaptive Burst Mode (ABM)
- 8.4.7 Low Power Mode (LPM)
- 8.4.8 First Standby Power Mode (SBP1)
- 8.4.9 Second Standby Power Mode (SBP2)
- 8.4.10 Startup Sequence
- 8.4.11 Survival Mode of VDD (INT_STOP)
- 8.4.12 Capacitor Voltage Balancing Function
- 8.4.13 Device Functional Modes for Bias Regulator Control
- 8.4.14
System Fault Protections
- 8.4.14.1 Brown-In and Brown-Out
- 8.4.14.2 Output Over-Voltage Protection (OVP)
- 8.4.14.3 Input Over Voltage Protection (IOVP)
- 8.4.14.4 Over-Temperature Protection (OTP) on FLT Pin
- 8.4.14.5 Over-Temperature Protection (OTP) on CS Pin
- 8.4.14.6 Programmable Over-Power Protection (OPP)
- 8.4.14.7 Peak Power Limit (PPL)
- 8.4.14.8 Output Short-Circuit Protection (SCP)
- 8.4.14.9 Over-Current Protection (OCP)
- 8.4.14.10 External Shutdown
- 8.4.14.11 Internal Thermal Shutdown
- 8.4.15 Pin Open/Short Protections
-
9 Application and Implementation
- 9.1 Application Information
- 9.2
Typical Application Circuit
- 9.2.1 Design Requirements for a 65-W USB-PD Adapter Application
- 9.2.2
Detailed Design Procedure
- 9.2.2.1 Input Bulk Capacitance and Minimum Bulk Voltage
- 9.2.2.2 Transformer Calculations
- 9.2.2.3 Clamp Capacitor Calculation
- 9.2.2.4 Bleed-Resistor Calculation
- 9.2.2.5 Output Filter Calculation
- 9.2.2.6 Calculation of ZVS Sensing Network
- 9.2.2.7 Calculation of BUR Pin Resistances
- 9.2.2.8 Calculation of Compensation Network
- 9.2.3 Application Curves
- 10Power Supply Recommendations
- 11Layout
- 12Device and Documentation Support
- 13Mechanical, Packaging, and Orderable Information
封裝選項(xiàng)
機(jī)械數(shù)據(jù) (封裝 | 引腳)
- RTW|24
散熱焊盤機(jī)械數(shù)據(jù) (封裝 | 引腳)
- RTW|24
訂購信息
9.2.2.2.3 Primary Winding Turns (NP)
The turn number on the primary side of the transformer (NP) is determined by two design considerations:
- The maximum flux density (BMAX) must be kept below the saturation limit (BSAT) of the magnetic core under the highest peak magnetizing current (IM+(MAX)) condition, a given cross-section area (AE) of the core geometry, and highest core temperature. When IFB = 0 A, such as VO soft-start or step-up load transient, the peak magnetizing current reaches IM+(MAX), since VCST = VCST(MAX) in those conditions. IM+(MAX) can be calculated based on the output power triggering an OPP fault (PO(OPP)) with VCST = VCST(OPP1) at VBULK(MIN).
Equation 27.
Equation 28.
- The AC flux density (ΔB) affects the core loss of a transformer. For a transition-mode active clamp flyback, the core loss is usually highest at high line, since the switching frequency is highest and duty cycle is smallest for a given load condition. The following equation is the ΔB calculation including the contribution of negative magnetizing current (IM-), used to put into the Steinmetz equation for more accurate core loss estimation. For VBULK ≥ NPS(VO+VF), IM- is calculated with VBULK divided by the characteristic impedance of LM and the lumped time-related switch-node capacitance (CSW). The expression of fSW is derived based on the triangular approximation of the magnetizing current, which also considers IM- effect over wide AC line condition.
Equation 29.
Equation 30.
Equation 31.
Equation 32.
Equation 33.
Equation 34.