LT1308A/LT1308B TheELECTRICAL CHARACTERISTICS l denotes the specifi cations which apply over the full operating temperaturerange, otherwise specifi cations are at TA = 25°C. Commercial Grade 0°C to 70°C. VIN = 1.1V, VSHDN = VIN, unless otherwise noted.SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITS IQ Quiescent Current Not Switching, LT1308A 140 240 μA Switching, LT1308B 2.5 4 mA VSHDN = 0V (LT1308A/LT1308B) 0.01 1 μA VFB Feedback Voltage l 1.20 1.22 1.24 V IB FB Pin Bias Current (Note 3) l 27 80 nA Reference Line Regulation 1.1V ≤ VIN ≤ 2V l 0.03 0.4 %/V 2V ≤ VIN ≤ 10V 0.01 0.2 %/V Minimum Input Voltage 0.92 1 V gm Error Amp Transconductance ∆I = 5μA 60 μmhos AV Error Amp Voltage Gain 100 V/V fOSC Switching Frequency VIN = 1.2V l 500 600 700 kHz Maximum Duty Cycle l 82 90 % Switch Current Limit Duty Cycle = 30% (Note 4) 2 3 4.5 A Switch VCESAT ISW = 2A (25°C, 0°C), VIN = 1.5V 290 350 mV ISW = 2A (70°C), VIN = 1.5V 330 400 mV Burst Mode Operation Switch Current Limit VIN = 2.5V, Circuit of Figure 1 400 mA (LT1308A) Shutdown Pin Current VSHDN = 1.1V l 2 5 μA VSHDN = 6V l 20 35 μA VSHDN = 0V l 0.01 0.1 μA LBI Threshold Voltage 196 200 204 mV l 194 200 206 mV LBO Output Low ISINK = 50μA l 0.1 0.25 V LBO Leakage Current VLBI = 250mV, VLBO = 5V l 0.01 0.1 μA LBI Input Bias Current (Note 5) VLBI = 150mV 33 100 nA Low-Battery Detector Gain 3000 V/V Switch Leakage Current VSW = 5V l 0.01 10 μA The l denotes the specifi cations which apply over the full operating temperature range, otherwise specifi cations are at TA = 25°C.Industrial Grade –40°C to 85°C. VIN = 1.2V, VSHDN = VIN, unless otherwise noted.SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITS IQ Quiescent Current Not Switching, LT1308A l 140 240 μA Switching, LT1308B l 2.5 4 mA VSHDN = 0V (LT1308A/LT1308B) l 0.01 1 μA VFB Feedback Voltage l 1.19 1.22 1.25 V IB FB Pin Bias Current (Note 3) l 27 80 nA Reference Line Regulation 1.1V ≤ VIN ≤ 2V l 0.05 0.4 %/V 2V ≤ VIN ≤ 10V l 0.01 0.2 %/V Minimum Input Voltage 0.92 1 V gm Error Amp Transconductance ∆I = 5μA 60 μmhos AV Error Amp Voltage Gain 100 V/V 1308abfb 3