NCP1910 High Performance Combo Controller for ATX Power Supplies Housed in a SO24WB package, the NCP1910 combines a state-of-the-art circuitry aimed to powering next generation of ATX NCP1910 124 SS Vboot Rt MU PG out Bridge ON/OFF ML BO adj. Vref V CC PG adj. DRV OVP2 GND/PGND FB Skip/AGND VCTRL CS/FF VM CS LBO Fold Figure 1. Pin Connections PIN DESCRIPTION Pin No Pin Name Function Pin Description 1 SS Soft-Start A capacitor to ground sets the LLC soft-start duration 2 Rt The LLC Feedback Pin A resistive arrangement sets the maximum and minimum switching frequencies with opto coupler-based feedback capabilities. 3 PG out The Open-Collector Power This pin is low when V is ok, opens when V passes bulk bulk Good Signal below a level adjusted by PGadj pin. 4 on/off Remote Control When pulled low, the circuit operates: the PFC starts first and once FB is in regulation, the LLC is authorized to work. When left open, the controller is in idle mode. 5 BO adj. Brown-Out Adjustment This pin sets the on and off levels for the PFC powering the LLC converter 6 Vref The 5 V Reference Pin This pin delivers a stable voltage for threshold adjustments 7 PG adj. The Power Good Trip Level From the Vref pin, a dc level sets the trip point for the PFC bulk voltage at which the PG out signal is down. 8 OVP2 Redundant OVP A fully latched OVP monitoring the PFC bulk independently from FB pin. 9 FB PFC Feedback Monitors the boost bulk voltage and regulates it. It also serves as a quick auto-recovery OVP 10 V PFC Error Amplifier Output PFC error amplifier compensation pin CTRL 11 V PFC Current Amplifier Output A resistor to ground sets the maximum power level M 12 LBO PFC Line Input Voltage Sensing Line feed forward and PFC brown-out 13 Fold PFC Fold Back This pin selects the power level at which the frequency starts to reduce gradually. 14 CS PFC Current Sense This pin senses the inductor current and also programs the maximum sense voltage excursion 15 CS/FF Fast-Fault Input When pulled above 1 V, the LLC stops and re-starts via a full soft-start sequence. 16 Skip/AGND Skip (B)/AGND (A) This pin is either used as the analog GND for the signal circuit (A) or for skip operation (B). 17 GND/PGND GND (B)/PGND (A) The controller ground for the driving loop (A) or the lump ground pin for all circuits (B) 18 DRV PFC Drive Signal The driving signal to the PFC power MOSFET 19 V The Controller Supply The power supply pin for the controller, 20 V max. CC 20 ML Lower-Side MOSFET Drive signal for the lower side half-bridge MOSFET 22 Bridge Half-Bridge This pin connects to the LLC half-bridge 23 MU Upper-Side MOSFET Drive signal for the upper side half-bridge MOSFET 24 V Bootstrapped Vcc The bootstrapped V for the floating driver boot CC