LT3505 E LECTRICAL CHARACTERISTICS The " denotes the specifi cations which apply over the full operatingtemperature range, otherwise specifi cations are at TA = 25°C, VIN = 12V, VBOOST = 17V, unless otherwise noted. (Note 2).PARAMETERCONDITIONSMINTYPMAXUNITS VIN Operating Range 3.6 36 V Undervoltage Lockout 3.1 3.35 3.6 V Feedback Voltage " 765 780 795 mV FB Pin Bias Current VFB = Measured VREF (Note 4) " 55 150 nA Quiescent Current Not Switching, RT = 75.0k 2.0 2.7 mA Quiescent Current in Shutdown VSHDN = 0V 0.01 2 µA Reference Line Regulation VIN = 5V to 36V 0.007 %/V Switching Frequency VFB = 0.7V, RT = 13.7k 2.70 3.01 3.30 MHz VFB = 0.7V, RT = 75.0k 675 750 825 kHz VFB = 0.7V, RT = 357k 180 200 220 kHz Maximum Duty Cycle RT = 75.0k " 90 94 % Error Amp Transconductance VFB = 0.78V 200 µA/V Error Amp Voltage Gain VFB = 0.78V 400 V/V VC Source Current VFB = 0V, VC = 1.5V 10 µA VC Sink Current VFB = 1V, VC = 1.5V 14 µA VC Switching Threshold Voltage IOUT = 0mA 0.9 V VC Clamp Voltage VFB = 0V 1.7 V RT Bias Voltage VFB = 0.6V 0.5 V VFB = 0V, RT = 75.0k 50 mV Switch Current Limit (Note 3) 1.4 1.75 2.2 A Switch VCESAT ISW = 1A 350 mV Switch Leakage Current 0.1 2 µA Minimum Boost Voltage Above Switch ISW = 1A 1.6 2.2 V BOOST Pin Current ISW = 1A 24 50 mA SHDN Input Voltage High 2.3 V SHDN Input Voltage Low 0.3 V SHDN Bias Current VSHDN = 2.3V (Note 5) 6 20 µA VSHDN = 0V 0.01 0.1 µA Note 1: Stresses beyond those listed under Absolute Maximum Ratings Note 3: Current limit guaranteed by design and/or correlation to static test. may cause permanent damage to the device. Exposure to any Absolute Slope compensation reduces current limit at higher duty cycle. Maximum Rating condition for extended periods may affect device Note 4: Current fl ows out of pin. reliability and lifetime. Note 5: Current fl ows into pin. Note 2: The LT3505E is guaranteed to meet performance specifi cations from 0°C to 85°C. Specifi cations over the –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls. The LT3505I specifi cations are guaranteed over the –40°C to 125°C temperature range. 3505fc 3