EVLALTAIR05T-5W ALTAIR05T-800 5 W wide range CV-CC optoless adapter demonstration board Data brief Features Universal input mains range: 90 - 264 Vac, frequency 45 - 65 Hz Output voltage: 5 V 1 A continuous operation Optoless constant voltage - constant current output regulation Standby mains consumption: < 100 mW 230 Vac Average efficiency: > 70% EMI: According to EN55022-Class-B Description Extremely low consumption under no load This board implements a 5 W (5 V / 1 A) wide conditions is ensured thanks to a controlled burst- range mains battery charger with constant mode operation that, along with the built-in high- voltage-constant current, tailored for AC-DC voltage startup circuit and the low operating chargers for mobile phones and adapters and current of the device, helps minimize the residual other hand-held equipment. input consumption. Although an auxiliary winding is required in the transformer to correctly perform The core of the application is the ALTAIR05T-800, CV/CC regulation, the chip is able to power itself the first All-primary sensing switching regulator directly from the rectified mains. This is useful of the new ALTAIR family. especially during CC regulation, where the The IC combines a high-performance low-voltage flyback voltage is generated by the winding drops. PWM controller chip and an 800 V, avalanche- rugged Power MOSFET in the same package. The PWM chip is a quasi-resonant (QR) current- mode controller IC specifically designed for QR ZVS (zero voltage switching at switch turn-on) flyback converters. The device is capable of providing constant output voltage (CV) and constant output current (CC) regulation using primary-sensing feedback. This eliminates the need for the optocoupler, the secondary voltage reference, as well as the current sensor, while still maintaining quite accurate regulation. In addition, it is possible to compensate the voltage drop on the output cable, so as to improve CV regulation on the externally accessible terminals. January 2012 Doc ID 022723 Rev 1 1/5 For further information contact your local STMicroelectronics sales office. www.st.com 5287 EVLALTAIR05T-5W Figure 1. Output characteristics > 9 9 9 9 , > 2/5 Doc ID 022723 Rev 1 287 & &