EVLSTCH03-36W-SR 36W USB charger with selectable output voltage (5-9-12 V 3A) based on STCH03L and SRK1000B Data brief The power circuit is a quasi-resonant (QR) flyback converter, with peak current mode control, based on the STCH03L IC. The circuit operates with secondary side constant voltage (CV) regulation through an optocoupler and is capable of providing constant output current (CC) regulation using primary sensing feedback. The STCH03L embeds a 650 V, non-dissipative, HV startup cell, which, along with the extremely low quiescent current and burst-mode management, helps minimize residual input consumption, thus achieving less than 20 mW under no-load condition. At secondary side, the SRK1000B controller Features implements synchronous rectification to increase Universal AC mains input voltage range: 90 V system efficiency: it controls the synchronous to 264 V rectifier MOSFET, driving its gate with minimal turn-on delay and maximizing the turn-off time Output voltage: 5 - 9 - 12 V selectable 3 A instant (through an adaptive mechanism) so that continuous operation the residual conduction of the SR MOSFET body Constant voltage (CV) regulation with diode after turn-off reduces to the target value of optocoupler and constant current (CC) 300 ns. regulation with primary side sensing The charger is designed to meet the most No-load consumption < 20mW at 230 VAC stringent energy saving recommendations (Eu (with load disconnected from charger) CoC rev. 5 - Tier 2 and EPS of DOE USA) as well 4 points average efficiency and 10% load as EMI regulation EN55022-Class-B for line efficiency in compliance with Eu CoC rev. 5 - conducted noise emissions. Tier 2 (2016) Line conducted EMI in compliance with EN55022 - Class B Small form factor (73 x 55 x 15 mm) RoHS compliant Description The EVLSTCH03-36W-SR shown in the image here is a 36 W wide-range mains USB charger demonstration board, with selectable output voltage (5 - 9 - 12 V 3 A output current), based on the STCH03L and SRK1000B. March 2019 DB3823 Rev 1 1/9 For further information contact your local STMicroelectronics sales office. www.st.com N 6 * * 6(/ 6(/ 6 N N N 5 7/ Q) N N 9 % %= 9 X) Q) N N 9 9 X) N /7 % 9 X+ 9 / %66 Q N 5 N 5 N 9R 5 S) 5 0 9 X 72 * N 9 *1 Q X) 9& * 67 . % : 1 5 . 65 4 : 1 67 9 5 % 7 X 9 X) 9 X) Q N 9 X X) N 9DF ) 3( 7 * X+ . / 9R Electrical diagram EVLSTCH03-36W-SR 1 Electrical diagram Figure 1. Electrical diagram WX 6+ 6+ 8)< %67 6 ) WX X) N N / / N N 6 1 8 9 ) 9+ % 6)+ & =1 * 7 6 N : 7+96 0 )6/ N +9/7 ) < 0 1 5 . 5 9 ) ) 9 (6 1 N + /& %3 0 & 5 / 1 & 21 % +6) 2/9 DB3823 Rev 1 +9 ) ~ + - -3 - 5 6( & & & & & & -3 5 ) ~ - ,1 17 6( 5 ) 56 +9 8 5 +9 9 8 5 1& & 9 & 5 )% *1 5 & =& 6( 5 8 & 5 5 5 4 5 5 5 5 5 5 5 & 8 4 5 5 1 & 4 5 & 5 8 28 5 *1 & 5 ,1 ,1 & 5 5 5 & 8 5 5 8 5 5 4 ) 5 5