LT3964 ELECTRICALCHARACTERISTICS The l denotes the specifications which apply over the full operatingtemperature range, otherwise specifications are at TA = 25°C. VIN1 = 12V, VEN/UVLO = 5V, CTRL1 = CTRL2 = 2V, PWM1 = PWM2 = 2Vunless otherwise noted.PARAMETERCONDITIONSMINTYPMAXUNITS FB1, FB2 OPENLED Threshold VFB – 43mV VFB – 53mV VFB – 63mV V FB1, FB2 SHORTLED Threshold l 250 270 mV FB1, FB2 Pin Input Bias Current Current Out of Pin, FB = 1V 20 200 nA Feedback Line Regulation 4V ≤ VIN1 ≤ 36V 0.001 %/V TSET Pin Voltage 630 mV TSET Pin Bias Current Current Out of Pin, TSET = 400mV 40 200 nA Oscillator RT Pin Voltage 0.96 V Switching Frequency RT = 357k l 186 200 214 kHz RT = 60.4k l 0.93 1.0 1.07 MHz RT = 27.4k l 1.86 2.0 2.14 MHz SYNC/CLKOUT Pin Resistance to GND 100 kΩ SYNC/CLKOUT Input High Threshold 1.5 V SYNC/CLKOUT Input Low Threshold 0.4 V SYNC/CLKOUT Output Duty Cycle CONFIG[6] = 1 (Clock Output Enabled) 30 50 70 % SYNC/CLKOUT Output Voltage High CONFIG[6] = 1 (Clock Output Enabled) 4 V SYNC/CLKOUT Output Voltage Low CONFIG[6] = 1 (Clock Output Enabled) 0.1 0.3 V SYNC/CLKOUT Output Rise Time CSYNC/CLKOUT = 50pF, CONFIG[6] = 1 (Clock 40 ns Output Enabled) SYNC/CLKOUT Output Fall Time CSYNC/CLKOUT = 50pF, CONFIG[6] = 1 (Clock 20 ns Output Enabled) Logic ALERT Output Low IALERT = 1mA 300 mV PWM1, PWM2 Input High Voltage l 1.18 1.3 V PWM1, PWM2 Input Low Voltage l 1.1 1.15 V PWM1, PWM2 Resistance to GND 280 kΩ Power Switch Top Switch On Resistance ISW = 1A 200 mΩ Top Switch Current Limit l 1.6 1.8 2 A Bottom Switch On Resistance ISW = 1A 180 mΩ Bottom Switch Current Limit 1.6 2 2.4 A SW Leakage Current VIN = 36V, VSW = 0V, 36V –1.5 1.5 µA Minimum Off Time 20 50 70 ns Minimum ON Time 20 40 65 ns PWMTG Gate Driver PWMTG ON Voltage (VISP1-PWMTG1, ISP1,2 = 36V 7.5 9.5 V VISP2-PWMTG2) PWMTG OFF Voltage (VISP1-PWMTG1, ISP1,2 = 36V 0 0.3 V VISP2-PWMTG2) PWMTG Turn-On Time CLOAD = 500pF, ISP1,2 = 36V 70 ns PWMTG Turn-Off Time CLOAD = 500pF, ISP1,2 = 36V 40 ns 3964fb 4 For more information www.linear.com/LT3964
