Ordering number : ENA0476A LA5779 Monolithic Linear IC Separately-excited Step-down LA5779 Electrical Characteristics at Ta = 25C, V = 3.3V O Ratings Parameter Symbol Conditions Unit min typ max Reference voltage V V = 15V, I = 1.0A 1.20 1.23 1.26 V OS IN O Efficiency V = 15V, I = 1.0A, Set V = 5V 84 % IN O O Switching frequency f V = 15V, I = 1.0A 128 160 192 kHz IN O Switching frequency when fshort V = 15V, V = 0V 15 30 45 kHz IN OS short-circuit protection is active Line regulation VLINE V = 8 to 20V, I = 1.0A 40 100 mV O IN O Load regulation VLOAD V = 15V, I = 0.5 to 1.5A 10 30 mV O IN O Output voltage temperature V /Ta Designed target value. * 0.5 mV/C O coefficient Ripple attenuation factor RREJ f = 100 to 120Hz 45 dB Output leak current Ileak V = 15V, SW = -0.4V 50 A O IN OUT Current limiter operating voltage I V = 15V 3.1 A S IN Operating current IV V = 15V 5.6 mA IN IN Standby current I V = 15V, ENA = 5V 200 A STBY IN ENA pin LOW voltage range V L 0.6 V ENA ENA pin HIGH voltage range V H 2.4 V V ENA IN Thermal shutdown operating TSD Designed target value. * 165 C temperature Thermal shutdown Hysteresis TSD Designed target value. * 15 C width * Design target value: No measurement made. Package Dimensions unit : mm (typ) 3079A Pd max -- Ta 10.0 10.4max 4.5 10.0 3.6 3 8.0 1.3 1001001.5mm Infinitely large heat sink 7.5 jc=5C/W 3 6.0 50501.5mm 5.6 Al heat sink plate tightening 4.0 3 30301.5mm torque 3.3 . 0.9 2.7 39N cm With No heat sink 2.0 silicone 1.75 1 5 grease applied. 0.8 4.5 0.45 0 --30 0 20 40 60 80 100 120 140 160 (1.6) 1.7 8.4 Ambient temperature, Ta -- C PCA00833 SANYO : TO-220-5H Pin Assignment (1) V (2) SW (3) GND (4) V (5) ENA IN OUT OS No.A0476-2/4 2.7 15.0 (8.8) 17.8 21.3 23.0 Allowable pwer dissipation, Pd max -- W