UCC28700 Constant-Voltage, Constant-Current PWM With Primary-Side Regulation | TI.com

UCC28700 (ACTIVE)

Constant-Voltage, Constant-Current PWM With Primary-Side Regulation

 

Description

The UCC28700 family of flyback power supply controllers provides Constant-Voltage (CV) and Constant-Current (CC) output regulation without the use of an optical coupler. The devices process information from the primary power switch and an auxiliary flyback winding for precise control of output voltage and current. Low start-up current, dynamically controlled operating states and a tailored modulation profile support very low standby power without sacrificing start-up time or output transient response.

Control algorithms in the UCC28700 family allow operating efficiencies to meet or exceed applicable standards. The output drive interfaces to a MOSFET power switch. Discontinuous Conduction Mode (DCM) with valley switching reduces switching losses. Modulation of switching frequency and primary current peak amplitude (FM and AM) keeps the conversion efficiency high across the entire load and line ranges.

The controllers have a maximum switching frequency of 130 kHz and always maintain control of the peak-primary current in the transformer. Protection features help keep primary and secondary component stresses in check. The UCC28700 allows the level of cable compensation to be programmed. The UCC28701, UCC28702, and UCC28703 devices allow remote temperature sensing using a Negative Temperature Coefficient (NTC) resistor while providing fixed cable-compensation levels.

Features

  • < 30-mW No-Load Power for 5-Star Rating
  • Primary-Side Regulation (PSR) Eliminates Opto-Coupler
  • ±5% Voltage and Current Regulation
  • 130-kHz Maximum Switching Frequency Enables High-Power
    Density Charger Designs
  • Quasi-Resonant Valley-Switching Operation for Highest
    Overall Efficiency
  • Patent-Pending Frequency-Jitter Scheme to Ease EMI
    Compliance
  • Wide VDD Range Allows Small Bias Capacitor
  • Clamped Gate-Drive Output for MOSFET
  • Protection Functions: Overvoltage, Low-Line, and
    Overcurrent
  • Programmable Cable Compensation (UCC28700 Only)
  • NTC Resistor Interface (UCC28701, UCC28702 and UCC28703
    Only) With Fixed Cable Compensation Options
  • SOT-23 Package

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Parametrics Compare all products in Flyback controllers

 
Control Method
Duty Cycle (Max) (%)
Frequency (Max) (kHz)
UVLO Thresholds On/Off (V)
Features
Operating Temperature Range (C)
Package Group
Rating
Package Size: mm2:W x L (PKG)
UCC28700 UCC28703 UCC28704 UCC28710 UCC28720 UCC28722 UCC28740 UCC28742
Current     Current     Current     Current     Current     Current     Current     Current    
99     99     99     99     99     99     99     99    
132     132     85     100     80     80     100     105    
21/8.1     21/8.1     21/7.7     21/8     21/7.7     21/7.7     21/7.75     22/7.7    
PSR
DCM    
PSR
DCM    
PSR
DCM    
PSR
DCM
HV Start-up
Green Mode
Input Line Monitor
Leading Edge Blanking
Light Load Efficiency
Low Power
Soft Start    
PSR
DCM
HV Start-up
Current Limiting
Green Mode
HV Start-up
Input Line Monitor
Leading Edge Blanking
Light Load Efficiency
Low Power
Soft Start    
PSR
DCM    
SSR
HV Start-up
DCM    
SSR
DCM    
-20 to 125     -20 to 125     -40 to 125     -40 to 125     -40 to 125     -40 to 125     -40 to 125     -40 to 125    
SOT-23 | 6     SOT-23 | 6     SOT-23 | 6     SOIC | 7     SOIC | 7     SOT-23 | 6     SOIC | 7     SOT-23 | 6    
Catalog     Catalog     Catalog     Catalog     Catalog     Catalog     Catalog     Catalog    
6SOT-23: 8 mm2: 2.8 x 2.9 (SOT-23 | 6)     6SOT-23: 8 mm2: 2.8 x 2.9 (SOT-23 | 6)     6SOT-23: 8 mm2: 2.8 x 2.9 (SOT-23 | 6)     7SOIC: 29 mm2: 6 x 4.9 (SOIC | 7)     7SOIC: 29 mm2: 6 x 4.9 (SOIC | 7)     6SOT-23: 8 mm2: 2.8 x 2.9 (SOT-23 | 6)     7SOIC: 29 mm2: 6 x 4.9 (SOIC | 7)     6SOT-23: 8 mm2: 2.8 x 2.9 (SOT-23 | 6)    

Design tool

WEBENCH® Designer UCC28700

 AC  DC  
AC Frequency  60 Hz  50 Hz
Use Isolated Output?
  Min   Max Range
VinRMS  V 85.00 to 480.00V
Vout  V 3.3 to 25V
Iout  A ≤ 10A
Ambient Temp  °C -20 to 125°C