Introduction

With the popularity of fast charging technology, the demand for high-power chargers among consumers has been increasing. Desktop charging stations, in particular, are well-received due to their high power output and multiple ports, simplifying charging for multiple devices simultaneously.

In the design of desktop charging stations, an efficient power architecture is key. To achieve high power output in a compact space while maintaining low heat generation and high efficiency, advanced power architectures are essential. Recent teardowns reveal that Anker's 250W GaN desktop charger adopts NXP's dual-phase interleaved PFC + LLC power architecture, which offers an optimized power factor, reduced input current harmonics, improved conversion efficiency, and superior thermal management. The following details the design and its key components.

NXP TEA2376DT

The TEA2376DT is a high-performance, digitally configurable two-phase interleaved PFC (Power Factor Correction) controller launched by NXP. Its unique digital architecture is based on a high-speed configurable hardware state machine, delivering exceptional real-time performance. The TEA2376DT operates in Discontinuous Conduction Mode (DCM) or Quasi-Resonant Mode (QR) with valley switching, significantly reducing switching losses and improving efficiency. Its two-phase interleaved design optimizes the input current waveform, enabling high power factor (PF) and low total harmonic distortion (THD).

The controller supports I²C interface programming for flexible adjustment of operating parameters and protection functions during development. It incorporates multiple operating modes, including phase shedding and burst mode, ensuring high efficiency across the entire load range. Under low load and standby conditions, it effectively minimizes power consumption to comply with energy efficiency regulations.

The TEA2376DT also features robust protection mechanisms, including internal and external over-temperature protection (OTP), overcurrent protection (OCP), dual overvoltage protection (OVP), and inrush current protection (ICP). These protections can be independently configured to latch mode, safe-restart mode, or multiple retry mode before latching. Additionally, the TEA2376DT integrates digital controllers and filters for optimized voltage and current control stability. Its high-precision valley detection and demagnetization detection ensure efficient and low-noise switching operation.

The design provides comprehensive monitoring and diagnostic capabilities, enabling real-time access to internal state parameters. It supports debugging and optimization through a GUI interface and is available in SO14 packaging, making it particularly suitable for applications such as high-definition and ultra-high-definition TVs, servers, desktop PCs, all-in-one computers, high-power adapters, and 5G power supplies.

• Type: Digitally configurable two-phase interleaved PFC controller.
• Operating Modes: Discontinuous Conduction Mode (DCM) and Quasi-Resonant Mode (QR) with valley switching.
• Control Architecture: High-speed configurable hardware state machine.
• Efficiency Features:
  • Interleaved two-phase design for low THD and high PF.
  • Burst mode and phase shedding for high efficiency in low-load conditions.
• Protections:
  • Internal and external over-temperature protection (OTP).
  • Overcurrent protection (OCP).
  • Dual overvoltage protection (OVP).
  • Inrush current protection (ICP).
  • Pin open/short detection and phase fail protection.
• Programmability: Adjustable through the I²C interface.
• Package: Narrow-body SO14.
• Power Levels: Supports up to 1000 W.
• Target Applications: UHD TVs, servers, PCs, high-power adapters, and 5G power supplies.
• Energy Compliance: Meets Energy Star, DOE, Eco-design, and EU CoC standards.
• Diagnostic Features: Real-time monitoring and GUI-based debugging. 

NXP TEA2226AT

The TEA2226AT from NXP is a digitally configurable LLC controller with integrated high-voltage startup and X-capacitor discharge. It includes an internal driver and supports parameter configuration via a graphical user interface (GUI). The TEA2226AT features multiple configurable protection functions and demonstrates excellent power consumption in no-load conditions.

Unlike traditional resonant topologies, the TEA2226AT employs a design that achieves high efficiency under low load by utilizing a low-power mode. This mode transitions between continuous switching (high-power mode) and burst mode, ensuring good efficiency across varying load conditions. By regulating the primary capacitor voltage, the controller can precisely detect output power and adjust its operating mode, including burst, low-power, and high-power modes.

The TEA2226AT integrates a low-voltage chip for digital control of output power, startup, initialization, and various protection features such as overcurrent protection (OCP), overvoltage protection (OVP), and capacitive mode regulation (CMR). Additionally, it includes a high-voltage insulated silicon chip for high-voltage startup, integrated drivers, level shifting, protection, and zero-voltage switching (ZVS).

From a hardware perspective, the TEA2226AT features a single-chip controller in a compact SO16 package. It integrates high-voltage startup, X-capacitor discharge, and high- and low-side driver circuits. Parameters such as operating frequency, soft start/stop, and precise mode transitions can be easily configured through the GUI.

The TEA2226AT supports a wide output power range (90W to 1000W) and requires minimal external components. It boasts ultra-low no-load input power consumption (<75mW) and maintains high efficiency across a broad load range, from low to high. This design not only reduces system costs but also simplifies power supply design while meeting the latest energy efficiency standards.

• Type: Digitally configurable LLC resonant controller.
• Key Features:
  • Integrated high-voltage startup and X-capacitor discharge.
  • Supports parameter adjustment via GUI.
  • Internal high- and low-side driver circuits.
  • Zero-voltage switching (ZVS) support.
• Operating Modes:
  • Continuous switching (high-power mode).
  • Burst mode (low-power mode).
  • Adaptive transition between modes based on load.
• Protection Functions:
  • Overcurrent protection (OCP).
  • Overvoltage protection (OVP).
  • Capacitive mode regulation (CMR).
• Power Efficiency:
  • No-load power consumption <75mW.
  • High efficiency across 90W to 1000W load range.
• Packaging: Single-chip SO16 package.
• Applications:
  • High-efficiency power supplies.
  • Energy-efficient adapters and chargers.
  • Wide-ranging power systems for industrial and consumer electronics.
• Energy Compliance: Meets modern energy-saving standards.

Summary of ChargerLAB

The dual-phase interleaved PFC architecture effectively reduces input current ripples and harmonics through interleaved signals, optimizing system efficiency. The combination of TEA2376DT and TEA2226AT achieves a highly efficient and reliable power architecture through digital control and precision protection features. This design is especially suitable for high-power desktop charging stations, offering exceptional performance and stability.