When engineers consider offline switchers for systems ranging from telecom and datacom equipment to PCs and industrial supplies, they mainly think of bulky AC/DC front-end solutions in a variety of forms such as bricks, modules, and open-frame. However, there are many applications where offline switchers powered by AC mains are needed in small packages or must occupy a small space on the motherboard. Some examples: USB adapters to power media players, e-readers, and GPS devices; and low-cost, offline LED drivers in lighting applications with high power factor to meet international requirements for total harmonic distortion (THD), EMC, and safety. Offline switchers are also used as standby power supplies in PCs and laptops, as well as in compact chargers for smartphones and other mobile devices. The point is that there are many applications where offline AC/DC switchers are needed in small form-factors.
This article will explore solutions from CUI Inc., Phihong USA, RECOM Power, and XP Power. Besides shedding some light on the properties of compact offline switchers, it will also identify key features and benefits of specific products available to engineers.
Compact external switchers
CUI, Inc., for instance, has readied an ultra-compact 5 W wall-plug adapter with integrated USB connector (Figure 1), the EPSA050100U-I38-EJ. With a footprint of just 1.61 x 1.18 in. (41 x 30 mm), the adapter is among the industry’s smallest AC/DC power supply to integrate USB connection, making it suitable for small mobile devices. In addition, it offers level V energy-efficiency compliance for green design requirements with a no-load power draw of less than 0.1 W. Rated for an output of 5 VDC at 1 A, the high-density EPSA050100U-I38-EJ operates at AC input voltages ranging from 90 to 264 VAC. Safety marks include UL/cUL, PSE, and LPS (limited power source). What is more, the external adapter also meets EN55022 Class B limits for conducted and radiated EMI and provides protection for overvoltage, overcurrent, and short-circuit conditions.
When engineers consider offline switchers for systems ranging from telecom and datacom equipment to PCs and industrial supplies, they mainly think of bulky AC/DC front-end solutions in a variety of forms such as bricks, modules, and open-frame. However, there are many applications where offline switchers powered by AC mains are needed in small packages or must occupy a small space on the motherboard. Some examples: USB adapters to power media players, e-readers, and GPS devices; and low-cost, offline LED drivers in lighting applications with high power factor to meet international requirements for total harmonic distortion (THD), EMC, and safety. Offline switchers are also used as standby power supplies in PCs and laptops, as well as in compact chargers for smartphones and other mobile devices. The point is that there are many applications where offline AC/DC switchers are needed in small form-factors.
This article will explore solutions from CUI Inc., Phihong USA, RECOM Power, and XP Power. Besides shedding some light on the properties of compact offline switchers, it will also identify key features and benefits of specific products available to engineers.
Compact external switchers
CUI, Inc., for instance, has readied an ultra-compact 5 W wall-plug adapter with integrated USB connector (Figure 1), the EPSA050100U-I38-EJ. With a footprint of just 1.61 x 1.18 in. (41 x 30 mm), the adapter is among the industry’s smallest AC/DC power supply to integrate USB connection, making it suitable for small mobile devices. In addition, it offers level V energy-efficiency compliance for green design requirements with a no-load power draw of less than 0.1 W. Rated for an output of 5 VDC at 1 A, the high-density EPSA050100U-I38-EJ operates at AC input voltages ranging from 90 to 264 VAC. Safety marks include UL/cUL, PSE, and LPS (limited power source). What is more, the external adapter also meets EN55022 Class B limits for conducted and radiated EMI and provides protection for overvoltage, overcurrent, and short-circuit conditions.
For more detail: Offline Switchers Come in Tiny Packages