Non-Isolated Buck Switchers Provide High-Voltage AC-DC Conversion with Low Standby Current for Always-On Appliances

Published  August 14, 2019   0
Non-Isolated Buck Switchers Provide High-Voltage AC-DC Conversion with Low Standby Current for Always-On Appliances

Diodes Incorporated launched the AP3917 family of universal AC-DC, non-isolated buck (step-down) power switchers for low-power applications, such as small appliances and IoT endpoints powered by an offline supply. The switcher family includes the AP3917B (170mA nominal load), AP3917C (270mA), and AP3917D (370mA). The new family of switchers will fulfil the increasing need of direct, non-isolated AC-DC conversion in a small form factor, with high levels of efficiency and low standby current which can be applied to small household, office, and industrial appliances that operate as standalone devices or as part of the IoT.

 

The new AP3917 family of buck switchers is designed to deliver highly efficient, offline power conversion for light-load applications with the support of discontinuous and continuous conduction modes. The AP3917 buck switcher is able to convert a full-wave rectified, AC input voltage between 85VAC and 265VAC to a nominal 8.0V DC output. The family saves space and BoM cost with non-isolated design which requires very few external components and no external transformer. The AP3917 buck switcher features no-load power consumption of less than 30mW which makes it well suited for small appliances that operate in standby mode for prolonged periods when connected to an AC outlet. The low-power credentials and small solution size of the AP3917 makes it a fit for IoT devices that are always connected but not always active.

 

Specifications of AP3917 family:

  • VCBO/ VDS: 650 V -700 V
  • Collector DC Current: 0.8 - 1 A
  • Startup Current: 26 µA
  • Operating Current: 200 µA
  • UVLO Threshold on/off: 6.5/4.5 V
  • Power Rating: 2-5 W
  • Standby Power: 30 mW
  • Cable Compensation:  0%

 

The more information of AP3917 family of universal AC-DC, non-isolated buck (step-down) power switchers is available from Diodes Incorporated.