Datasheet LT1308A, LT1308B (Analog Devices) - 5

LT1308A/LT1308B
TYPICAL PERFORMANCE CHARACTERISTICS LT1308B Switch Current Limit vs Switch Saturation Voltage 12V Output Effi ciency Duty Cycle vs Current
90 4.0 500 V 85 IN = 5V 400 80 VIN = 3.3V 3.5 85°C 75 (mV) 300 25°C 70 3.0 CESAT 200 65 –40°C EFFICIENCY (%) CURRENT LIMIT (A) SWITCH V 60 2.5 100 55 50 2.0 0 1 10 100 1000 0 20 40 60 80 100 0 0.5 1.0 1.5 2.0 LOAD CURRENT (mA) DUTY CYCLE (%) SWITCH CURRENT (A) 1308A/B G04 1308 • G05 1308 G06
FB, LBI Bias Current vs Low Battery Detector Reference SHDN Pin Bias Current vs Voltage Temperature vs Temperature
50 80 203 70 202 40 –40°C 60 201 LBI 30 50 200 25°C 40 (mV) 199 85°C REFV PIN CURRENT (μA) 20 30 198 BIAS CURRENT (nA) FB SHDN 20 197 10 10 196 0 0 195 0 2 4 6 8 10 –50 –25 0 25 50 75 100 –50 –25 0 25 50 75 100 SHDN PIN VOLTAGE (V) TEMPERATURE (°C) TEMPERATURE (°C) 1308 G07 1308 • G08 1308 • G09
Oscillator Frequency vs LT1308A Quiescent Current vs Feedback Pin Voltage vs Temperature Temperature Temperature
800 180 1.25 750 170 1.24 700 160 1.23 650 150 1.22 600 140 (V) FBV1.21 550 130 FREQUENCY (kHz) 1.20 500 QUIESCENT CURRENT (μA) 120 1.19 450 110 400 100 1.18 –50 –2.5 0 25 50 75 100 –50 –25 0 25 50 75 100 –50 –25 0 25 50 75 100 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) 1308 • G10 1308 • G11 1308 • G12 1308abfb 5