PMIC - AC DC Converters, Offline Switchers

Part Number	Description / PDF	Quantity
UCC2813D-2G4 Texas Instruments	IC REG CTRLR BST FLYBK PWM 8SOIC	0
UC3848DW Texas Instruments	SWITCHING CONTROLLER	0
UCC3804DTRG4 Texas Instruments	IC REG CTRLR PWM CM 8SOIC	0
UCC28702DBVR Texas Instruments	IC REG CTRLR FLYBK ISO SOT23-6	0
UCC28083PW Texas Instruments	UCC28083 CURRENT MODE PUSH-PULL	13606
UCC3802N Texas Instruments	IC REG CTRLR PWM CM 8DIP	39
UCC3889DG4 Texas Instruments	IC PWM FLYBACK ISOLATED VM 8SOIC	0
UCC3895DWTRG4 Texas Instruments	UCC3895 BICMOS ADVANCED PHASE SH	1124
UCC28610DR Texas Instruments	IC CTLR PWM GREEN MODE 8-SOIC	1320
UCC2889DTR Texas Instruments	UCC2889 OFF-LINE POWER SUPPLY CO	22981
UCC28632D Texas Instruments	UCC28632 HIGH POWER FLYBACK CONT	6100
UCC2895MDWREP Texas Instruments	IC REG CTRLR PWM CM/VM 20-SOIC	1589
UCC28730DR Texas Instruments	IC REG CTRLR FLYBK ISO 7SOIC	2548
UCC28911DR Texas Instruments	IC OFF-LINE SWITCH PWM 7SOIC	13137
UCC25706QDRQ1 Texas Instruments	UCC25706-Q1 AUTOMOTIVE 8V TO 15V	26292
UC2851N Texas Instruments	UC2851 PROGRAMMABLE, OFF-LINE, P	2526
LM5021MM-2/NOPB Texas Instruments	IC PWM CTRLR AC-DC CURR 8VSSOP	6248
UCC28710D Texas Instruments	IC REG CTRLR FLYBK ISO 7SOIC	1345
UCC28700DBVT Texas Instruments	IC REG CTRLR FLYBK ISO SOT23-6	4082
UC2879DWG4 Texas Instruments	UC2879 PHASE SHIFT RESONANT CONT	50

PMIC - AC DC Converters, Offline Switchers

1. Overview

AC-DC converters and offline switchers are critical subcategories of Power Management Integrated Circuits (PMICs) that convert alternating current (AC) from mains power to direct current (DC) for electronic devices. Offline switchers directly regulate input voltage without requiring a line-frequency transformer, enabling compact and efficient designs. These components are essential in modern electronics for ensuring stable power delivery, energy efficiency, and compliance with global standards like Energy Star and CoC Tier-2.

2. Main Types and Functional Classification

Type	Functional Features	Application Examples
Flyback Controllers	Isolated topology with energy storage in transformer; suitable for low-to-medium power	Mobile chargers, adapter supplies
Forward Controllers	Higher efficiency for medium-to-high power; requires reset circuitry	Industrial power supplies, telecom rectifiers
Resonant Controllers	ZVS/ZCS techniques for minimal switching losses; high-frequency operation	High-end server PSUs, wireless charging
PFC-Precursors	Boosts power factor to meet regulatory limits; often paired with main converters	Appliances, LED drivers

3. Structure and Components

Typical physical structure includes:

Package Types: DIP, SOP, QFN, or custom power packages
Internal Components:
- Power MOSFET/BJT switches
- PWM/PFM controllers
- Voltage/current feedback circuits
- Protection modules (OVP, OCP, OTP)
- High-voltage startup circuits

Technical composition integrates primary-side regulation (PSR) or secondary-side feedback with optocouplers, often supporting synchronous rectification for efficiency optimization.

4. Key Technical Parameters

Parameter	Description	Importance
Input Voltage Range	85-265V AC or 120-400V DC	Global compatibility and surge tolerance
Output Power	1W-500W depending on topology	Determines application scope
Switching Frequency	20kHz-2MHz	Affects EMI, transformer size, and efficiency
Efficiency	85%-96% (varies with load)	Thermal performance and energy costs
Protection Features	Overvoltage, overcurrent, thermal shutdown	System reliability and safety compliance

5. Application Fields

Consumer Electronics: Phone chargers, notebook adapters, smart home devices
Industrial: Automation equipment, PLCs, test instruments
Medical: Isolated power supplies for diagnostic equipment
Telecom: 48V rectifiers, base station power systems
Automotive: On-board chargers, vehicle AC-DC systems

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Features
Texas Instruments	UCC28780	High-frequency resonant controller with GaN support
STMicroelectronics	L6565	Current-mode flyback controller for adapters
Infineon	ICE3BR1765	Integrated CoolSET for SMPS
ON Semiconductor	NCP1342	Quasi-resonant flyback controller
Monolithic Power Systems	MP44010	Primary-side regulated controller

7. Selection Guidelines

Define input/output requirements (voltage, current, power)
Choose topology based on isolation needs and efficiency targets
Evaluate protection features for mission-critical applications
Consider package thermal performance (e.g., exposed pads)
Verify compliance with standards (UL, CE, FCC)
Balance cost vs. integration level (e.g., controller vs. digital PMIC)

Case Study: For a 65W USB-C laptop adapter, select a high-frequency resonant controller with synchronous rectification to achieve >92% efficiency and compact form factor.

8. Industry Trends

Integration: Combining PFC + LLC stages into single chips
Wide Bandgap: SiC/GaN FETs enabling >1MHz switching
Digital Control: Programmable PMICs with real-time optimization
Green Standards: Meeting EU CoC Tier-2 no-load <10mW requirements
AEC-Q Compliance: Growth in automotive-grade offline converters