Diodes' AP3171 is a synchronous-rectification buck DC-DC converter with a constant voltage (CV), constant current (CC) output compatible with quick charge 2.0. It provides a high-performance, compact footprint solution for all types of tablet and smartphone chargers. The AP3171 sets the output voltage and full current capabilities to 5 V / 2 A, 9 V / 2 A, or 12 V / 1.5 A, respectively, as per QC 2.0 function, and automatically provides a backwards compatible 5 V output for devices that are not compatible with QC 2.0. As a charger solution the AP3171 provides externally adjustable cable compensation. At heavy loads, the AP3171 switches at a fixed 120 kHz; while under light and no load conditions, its zero current detection (ZCD) function causes it to enter into discontinuous current mode (DCM) improving the power conversion efficiency. The AP3171 has versatile protection functions including input voltage under-voltage lockout (UVLO), output voltage over-voltage protection (OVP), and under voltage protection (UVP), inductor peak current limit, and internal over-temperature protection (OTP).

Features

• Single chip solution: synchronous DC-DC buck converter with QC 2.0 decoder
  • Simplifies the system BOM and PCB layout
• QC 2.0 function compatible
  • Provides quick charge function in all 12 V charger applications
• Power limited to 18 W at 9 V / 12 V by adaptive constant current (CC) function
  • Protecting the overall system from over-power conditions
• Cable compensation adjustable by external components
  • Increases the system design flexibility
• Over-peak current protection, over voltage protection, under voltage protection, internal OTP
  • Increases system reliability and robustness

Applications

• Aftermarket phone / tablet chargers
• Multiple USB charger port strips
• General DC-DC chargers