LT1941 TheELECTRICAL CHARACTERISTICS l denotes the specifi cations which apply over the full operating temperaturerange, otherwise specifi cations are at TA = 25°C. VIN, VBIAS1, VBIAS2 = 5V, VBOOST1, VBOOST2 = 8V, unless otherwise noted. (Note 2)PARAMETERCONDITIONSMINTYPMAXUNITS Switch 2 Leakage Current 0.01 10 μA Minimum Boost Voltage Above Switch (Note 4) 1.8 2.5 V Maximum Duty Cycle l 78 88 % 1.5A Inverting/Boost FB3 Voltage 1.23 1.25 1.27 V l 1.22 1.27 V FB3 Pin Bias Current l 800 1400 nA NFB Voltage l –15 0 15 mV NFB Pin Bias Current l 60 500 nA NFB3 Voltage (VFB3-VNFB) 1.212 1.24 1.258 V l 1.205 1.260 V FB3 Pin Output Current VFB3 = 1.35V, VNFB = –0.1V l 150 350 μA PGOOD3 Threshold Offset VFB Rising 120 mV Error Amplifi er Transconductance 800 μMhos Error Amplifi er Voltage Gain 150 V/V VC Switching Threshold 1.1 V VC3 to Switch Current Gain 5 A/V Frequency Shift Threshold on FB3 0.65 V Switch 3 Current Limit (Note 5) l 1.5 2 2.9 A Switch 3 VCESAT ISW = 1A 240 320 mV BIAS2 Pin Current ISW = 1A 30 45 mA Switch 3 Leakage Current 0.01 10 μA Maximum Duty Cycle l 77 86 % Note 1: Stresses beyond those listed under Absolute Maximum Ratings Note 4: This is the minimum voltage across the boost capacitor needed to may cause permanent damage to the device. Exposure to any Absolute guarantee full saturation of the internal power switch. Maximum Rating condition for extended periods may affect device Note 5: Current limit is guaranteed by design and/or correlation to static reliability and lifetime. test. Note 2: The LT1941E is guaranteed to meet performance specifi cations Note 6: This IC includes overtemperature protection that is intended from 0°C to 70°C. Specifi cations over the –40°C to 85°C operating to protect the device during momentary overload conditions. Junction temperature range are assured by design, characterization and correlation temperature will exceed 125°C when overtemperature protection is active. with statistical process controls. Continuous operation above the specifi ed maximum operating junction Note 3: Current limit is guaranteed by design and/or correlation to static temperature may impair device reliability. test. Slope compensation reduces current limit at higher duty cycles. Note 7: Guaranteed by design, not 100% tested. 1941fb 4