AP6320 Synchronous Buck Converters

By Diodes Incorporated 40

AP6320 Synchronous Buck Converters

Diodes' AP63200, AP63201, AP63203, and AP63205 are 2 A synchronous buck converters with a wide input voltage range of 3.8 V to 32 V supporting 5 V, 12 V, and 24 V power supplies. Integrated 125 mΩ high-side and a 68 mΩ low-side power MOSFETs provide high-efficiency step-down DC-DC conversion. The AP63200, AP63203, and AP63205 utilize pulse frequency modulation (PFM) with an ultra-low quiescent current of 22 µA, which provides efficiencies up to 80% and 88% during light load conditions of 1 mA and 5 mA, respectively. The AP63203 and AP63205 are fixed output buck converters with optimized design for reduced electromagnetic interference (EMI). The AP63201 operates in pulse width modulation (PWM) where the switching frequency is relatively fixed regardless of output load. All members have optimized EMI, utilizing frequency spread spectrum (FSS) with a switching frequency jitter of ±6% further reduces EMI. Further EMI improvements are achieved through its proprietary gate driver scheme which reduces switching node ringing without sacrificing MOSFET turn-on and turn-off times. The device is available in a low-profile TSOT26 package.


  • VIN 3.8 V to 32 V; withstand 40 V 400 ms input surge
    • Works across the full voltage range of consumer electronics, industrial and appliance applications
  • Wide output voltage range: 0.8 V to near 100% of VIN (LDO mode)
    • Duty cycle extends to 100% essentially supporting LDO-like functionality
  • Ultra-low (22 µA) quiescent current (IQ)
    • Maximizes light load efficiency
  • Designed for best-in-class EMI performance
    • SW ringing resistant at 4 ns rise time; frequency spread spectrum (FSS)
  • Simple PCB layout design: pinout supports single layer PCB
    • Minimal number of external components, short current loops on PCB further easing EMI issues
  • Pinout compatible with 3 A version (expected Q2 2019)
  • White goods and small home appliances
  • Flat screen TV sets and monitors
  • Power tools and laser printers
  • Gaming consoles
  • Set-top boxes
  • Home audio
  • Network systems