LT3697 e lecTrical characTerisTics The l denotes the specifications which apply over the full operatingtemperature range, otherwise specifications are at TA = 25°C. VIN = 12V, VEN = 12V unless otherwise noted. (Notes 3, 6) PARAMETERCONDITIONSMINTYPMAXUNITS Switching Frequency RT = 22.1k l 1.8 2 2.25 MHz RT = 63.4k l 0.9 1 1.12 MHz RT = 453k l 250 300 350 KHZ Foldback Frequency RT = 63.4k, VSYS = 0V 240 kHz Minimum Switch On-Time ISW = 0.9A 100 160 ns Minimum Switch Off-Time ISW = 0.9A 140 210 ns Switch Current Limit (Note 8) l 4.3 5.3 6.7 A Switch VCESAT ISW = 2A 220 mV SW Leakage Current VEN = 0.3V, VBST = 5V, VSW = 0V 0.1 1 µA Minimum BST Voltage (Note 9) ISW = 2A 1.6 2.2 V BST Current ISW = 2A 35 65 mA EN Input Voltage High l 2.5 V EN Input Voltage Low l 0.3 V EN Current VEN = 2.5V 1 2 μA SENSE Voltage to Trigger FLT Percentage of Nominal Sense Voltage 97 99.5 100 % FLT Blanking 0.5 1.5 4 ms FLT Leakage VFLT = 5V 0.1 1 μA FLT Sink Current VFLT = 0.3V l 100 180 μA SYNC Threshold l 0.4 0.7 1 V SYNC Current VSYNC = 5V 0.1 μA Note 1: Stresses beyond those listed under Absolute Maximum Ratings to protect the device during momentary overload conditions. Junction may cause permanent damage to the device. Exposure to any Absolute temperature will exceed 150°C when overtemperature protection is active. Maximum Rating condition for extended periods may affect device Continuous operation above the specified maximum operating junction reliability and lifetime. temperature may impair device reliability. Note 2: Absolute maximum voltage at VIN and EN is 60V for nonrepetitive Note 6: Polarity specification for current into a pin is positive and out of 1 second transients, and 35V for continuous operation. a pin is negative. All voltages are referenced to GND unless otherwise Note 3: The LT3697E is guaranteed to meet performance specifications specified. MAX and MIN refer to absolute values. from 0°C to 125°C junction temperature. Specifications over the –40°C Note 7: SENSE Voltage is defined as the differential voltage applied across to 125°C operating junction temperature range are assured by design, the sense amplifier inputs, or VISP – VISN. SENSE voltage and VSENSE are characterization and correlation with statistical process controls. The synonymous. LT3697I is guaranteed over the full –40°C to 125°C operating junction Note 8: Switch current limit is guaranteed by design and/or correlation to temperature range. High junction temperatures degrade operating static test. Slope compensation reduces switch current limit at higher duty lifetimes. Operating lifetime is derated at junction temperatures greater cycles. than 125°C. Note 9: Boost voltage is the minimum voltage across the boost capacitor Note 4: Note that the maximum ambient temperature consistent with needed to guarantee full saturation of the switch. these specifications is determined by specific operating conditions in conjunction with board layout, the rated package thermal impedance and other environmental factors. Note 5: This IC includes overtemperature protection that is intended 3697f 4 For more information www.linear.com/LT3697