Diodes Incorporated

Demoboard AP63356/7 EVB

3.5A Low Iq Synchronous Buck with Enhanced EMI Reduction

Topology: Buck
Input Voltage (min.): 3.80 V
Input Voltage (max.): 32.00 V
Output 1: 12.00 V / 3.500 A


The AP63356 and AP63357 are 3.5A synchronous buck converters with up to 32V wide input voltage range.The AP63356/7 fully integrated a 83mΩ high-side and a 43mΩ low-side MOSFET to provide high efficiencystep-down DC/DC conversion at their rated load. The regulators adopt peak current mode control with the integrated compensation network, which makes them easily to be used by minimizing the off-chip. The AP63356/7 is fixed frequency Continuous Conduction Mode (CCM). The regulators are an ElectromagneticInterference (EMI) friendly buck converters with implementing optimized design for EMI reduction. The regulators has proprietary designed gate driver scheme to resist switching node ringing without sacrificing MOSFET turn on and turn off time. which further erases high frequency radiation EMI noise caused by the MOSFETs hard switching. The regulators offer output overvoltage protection, cycle-by-cycle peak currentlimit, and thermal shutdown protection. The devices are available in a low-profile 2x3mm DFN package


  • VIN 3.8V to 32V
  • 3.5A Continuous Output Current
  • 0.8V ± 1% Reference Voltage
  • 22μA Ultralow Quiescent Current (Pulse Frequency Modulation)
  • 450kHz Switching Frequency
  • Pulse Width Modulation (PWM) Regardless of Output Load (AP63356)
  • Supports Pulse Frequency Modulation (PFM) (AP63357)
  • Up to 86% Efficiency at 5mA Light Load
  • Proprietary Gate Driver Design for Best EMI Reduction
  • Frequency Spread Spectrum (FSS) to Reduce EMI
  • Low-Dropout (LDO) Mode
  • Power Good Indicator with 5MΩ Internal Pull-up
  • Precision Enable Threshold to Adjust UVLO
  • Protection Circuitry
  • Undervoltage Lockout (UVLO)
  • Output Undervoltage Protection (UVP)
  • Cycle-by-Cycle Peak Current Limit
  • Thermal Shutdown
  • Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
  • Halogen and Antimony Free. “Green” Device (Note 3)


  Order Code SPEC Product series RDC
Version Samples
74439346100 PDF WE-XHMI SMT Power Inductor 26.5 10 5 7.6 16 SMT
74439346068 PDF WE-XHMI SMT Power Inductor 17.6 6.8 6.5 10 21.5 SMT
74439346047 PDF WE-XHMI SMT Power Inductor 13 4.7 7.4 14.7 25 SMT
74439344022 PDF WE-XHMI SMT Power Inductor 10.5 2.2 8 16 36 SMT