PMIC - AC DC Converters, Offline Switchers

Part Number	Description / PDF	Quantity
VIPER12ASTR-E STMicroelectronics	IC OFFLINE SWIT PWM SMPS 8SOIC	439
ALTAIR04-900 STMicroelectronics	IC OFFLINE SWITCH PWM 16SOIC	2653
L6699DTR STMicroelectronics	IC CTLR OFFLINE PWR SUPP 16SOIC	5026
VIPER06HS STMicroelectronics	IC OFFLINE SWITCH PWM 10-SSOP	4000
VIPER06HN STMicroelectronics	IC OFFLINE SWITCH PWM SMPS 7DIP	4014
VIPER16LDTR STMicroelectronics	IC OFFLINE CONV PWM OTP 16SOIC	0
VIPER319XDTR STMicroelectronics	ENERGY SAVING OFF-LINE HIGH VOLT	2485
VIPER317LDTR STMicroelectronics	ENERGY SAVING OFF-LINE HIGH VOLT	2000
VIPER28HN STMicroelectronics	IC OFFLINE CONV PWM OVP 8DIP	1109
VIPER50-E STMicroelectronics	IC SWIT PWM SMPS CM PENTAWATT5	0
VIPER22ASTR-E STMicroelectronics	IC OFFLINE SWIT PWM SMPS 8SOIC	4909
VIPER26HDTR STMicroelectronics	IC OFFLINE CONV PWM 800V 16-SOIC	0
VIPER37LDTR STMicroelectronics	IC AC-DC CONVERTER FIXED 16SOIC	50
VIPER013XS STMicroelectronics	IC OFFLINE CONV PWM 10SSOP	0
VIPER318XDTR STMicroelectronics	ENERGY SAVING OFF-LINE HIGH VOLT	490
VIPER16HDTR STMicroelectronics	IC OFFLINE CONV PWM 16SOIC	605
VIPER25LDTR STMicroelectronics	IC OFFLINE CONV PWM OVP OCP 16SO	0
VIPER27HN STMicroelectronics	IC OFFLINE CONV PWM OVP 7DIP	895
VIPER38HD STMicroelectronics	IC AC-DC CONVERTER FIXED 16SOIC	0
VIPER222LSTR STMicroelectronics	HIGH VOLTAGE CONVERTER	8282

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