PN8275+PN8308H six-level energy efficiency 12V3A adapter solution

With the implementation of DoE Level VI energy efficiency and CoC V5 Tier 2, synchronous rectification replacing Schottky has become a general trend. LIMEC has launched a new generation of streamlined peripheral 12V3A six-level energy efficiency charger/adapter solution: PN8275+PN8308H peripheral BOM is reduced by 20%, efficiency is as high as 87%, meeting the traditional 12V3A six-level energy efficiency synchronous rectification solution that meets the six-level energy efficiency.

Overview of the 6-level energy efficiency 12V3A adapter solution:
PCBA size: 39.0mm*86.0mm
Input voltage: 90~265Vac full voltage
Output power: 36W (Typical)
Average efficiency: ≥88.3% (meet CoC V5 Tier2 6-level energy efficiency requirements)
Standby power consumption: <50mW (Vin=265Vac)
Input undervoltage protection, input overvoltage protection, output overvoltage protection, output overcurrent protection, etc.

PN8275 is a current mode switching power supply chip with integrated high-voltage startup, combining multi-mode hybrid modulation technology and X capacitor discharge function to achieve 6-level energy efficiency, and complies with IEC 62368-1:2014 standard requirements (CB certificate number: DK-76617-UL); PN8275 provides comprehensive protection functions including input mains undervoltage protection, mains overvoltage protection, output overvoltage protection, OTP, OCP, secondary rectifier short circuit protection, etc.

PN8308H includes DCM/CCM mode synchronous rectification controller and 80V/10mΩ intelligent power MOSFET, which is used to replace the secondary rectification Schottky diode in the 9-20V flyback system. PN8308H has a simplified periphery and adopts unique current tracking technology, which can be quickly turned off within 50ns, improve the system EMI characteristics, completely avoid direct-through damage and reduce the SR switch peak voltage.

How to achieve low standby power consumption: PN8275 has a built-in 850V high-voltage startup and discharge module, and can easily achieve 50mW standby power consumption at 265Vac!
How to improve conversion efficiency: PN8308H has a built-in 80V/10mΩ smart power MOSFET, and the average efficiency at 115Vac/230Vac is greater than 92%!
How to simplify EMC design: PN8275 has a built-in X-capacitor discharge module, which can simplify the conduction design by increasing the X-capacitor; PN8308H uses a unique current tracking technology to reduce the SR switch peak voltage and improve radiation by more than 3dB!

Highlights of the 12V3A six-level energy-efficient adapter solution:
Output specification: 12V/3A
Built-in 850V high-voltage module to achieve X discharge function
HV pin can achieve accurate AC power abnormality protection: OVP, Brown in/out
High-voltage startup + multiple working modes + synchronous rectification technology to meet CoC V5 Tier 2,

Although DCM mode synchronous rectification technology is mature, its application is generally limited to low-power chargers. CCM mode synchronous rectification supports any mode of primary side chip, so it has higher application power and wider application occasions. PN8308 is widely used in 12V2A-12V3A six-level energy efficiency adapters due to its streamlined periphery, excellent EMC performance, support for any working mode, SMD packaging and no need for heat sink.