SI-8405NH

1-1-2 Switching Mode Regulator ICs SI-8405NH Surface-Mount, Synchronous Rectifier Step-down Switching Mode Regulator Control ICs ■Features • Input voltage (Vin): 3.0 to 5.5 V • Synchronous rectification • Output voltage precision ± 1.2% • Oscillation Frequency: 750 kHz • Overcurrent protection (Overcurrent value can be set by the external resistor.) • Output can be disabled • Undervoltage Lock Out • Soft start function • High-speed load response ■Absolute Maximum Ratings Parameter Input Voltage (VIN pin) EN/SS Pin Input Voltage Junction Temperature Storage Temperature Symbol VIN VEN Tj Tstg Ratings 6 –0.3 to VIN +125 –40 to +150 Unit V V °C °C ■Recommended Operating Conditions Parameter Input Voltage Range Output Voltage Range Operating Temperature Range Symbol VIN Vo Top Ratings 3 to 5.5 0.5 to 4 –30 to +85 Unit V V °C ■Applications • Power supply for LCD modules • Power supply for notebook PC • Onboard local power supplies • Power supply for LBP/PPC ■Electrical Characteristics Parameter Reference Voltage Circuit Current (VIN Pin) Standby Current (VIN Pin) On Time High Side Drive Block ON Resistance (Pulled Up) High Side Drive Block ON Resistance (Pulled Down) Low Side Drive Block ON Resistance (Pulled Up) Low Side Drive Block ON Resistance (Pulled Down) Overcurrent detection voltage EN/SS Pin Current EN/SS Low Level Voltage Symbol Vref Conditions Iop Conditions Istd Conditions Ton Conditions RonHH Conditions RonHL Conditions RonLH Conditions RonLL Conditions Vlim Conditions Iss Conditions Vcelo Conditions Vth (SS Start) EN/SS Threshold Voltage Conditions Vth (ON) Conditions Undervoltage Lock Out (VIN) Vuvloh Vuvlol 2.4 VIN=5V 2.9 0.8 0 VIN=5V 0.9 VIN=5V 2.4 1.0 7 40 Ratings min. 0.494 typ. 0.500 VIN=5V, VEN=5V 5 VIN=5V, VEN=H 400 VIN=5V, VEN=L 0.65 VIN=5V, Vo=2.5V 3.5 VIN=5V, ID=0.1A 3.5 VIN=5V, ID=0.1A 3.5 VIN=5V, ID=0.1A 3.5 VIN=5V, ID=0.1A 50 VIN=5V 10 VIN=5V 0.8 13 60 600 max. 0.506 (Ta=25°C) Unit V mA µA µS Ω Ω Ω Ω mV µA V V V V V 84 ICs SI-8405NH ■External Dimensions (SOP8) 5.1±0.4 1.27 0.4±0.1 0.15+0.1 –0.05 0.5±0.1 (Unit : mm) Pin Assignment q VIN w EN/SS e VO r VSENS t GND y DRVL u DRVH i ISEN Plastic Mold Package Type Flammability : UL 94V-0 Product Mass : Approx. 0.1 g 8 7 6 5 1 2 3 4 0.995max. 1.55±0.15 1.5±0.1 0.10 0.4±0.1 0.12 M ■Block Diagram Vin 0.05±0.05 0~ 10 ° 1.27 4.4±0.2 6.2±0.3 UVLO ISEN OCP H_DRV H_Side_ Drive DRVH UVLO Synchronous include Dead-time L_DRV EN SS/EN Gate DRV L_Side_ Drive DRVL GND Vo Comp – + + VSNS On-Timing Generator Vref Zep Vref 1 0.5V SS_CON ■Typical Connection Diagram Vin 1 EN Vin SI-8400N EN/SS ISEN DRVH DRVL C4 8 7 6 R1 R4 Q1 Q2 D1 5 C1 2 C3 L1 + Vo C2 4 VSNS Vo 3 GND R2 R3 C1 C2 C3 C4 L1 D1 : : : : : : 10µF 330µF 0.022µF 0.1µF 2.7µH SJPJ-L4 (Sanken) ICs 85