LTC3631 elecTrical characTerisTicsThe l denotes the specifications which apply over the full operatingjunction temperature range, otherwise specifications are for TA = 25°C (Note 2). VIN = 10V, unless otherwise noted. SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITSInput Supply (VIN) VIN Input Voltage Operating Range 4.5 45 V UVLO VIN Undervoltage Lockout VIN Rising l 3.80 4.15 4.50 V VIN Falling l 3.75 4.00 4.35 V Hysteresis 150 mV OVLO VIN Overvoltage Lockout VIN Rising 47 50 52 V VIN Falling 45 48 50 V Hysteresis 2 V IQ DC Supply Current (Note 3) Active Mode 125 220 µA Sleep Mode 12 22 µA Shutdown Mode VRUN = 0V 3 6 µA Output Supply (VOUT/VFB) VOUT Output Voltage Trip Thresholds LTC3631-3.3V, VOUT Rising l 3.260 3.310 3.360 V LTC3631-3.3V, VOUT Falling l 3.240 3.290 3.340 V LTC3631-5V, VOUT Rising l 4.940 5.015 5.090 V LTC3631-5V, VOUT Falling l 4.910 4.985 5.060 V VFB Feedback Comparator Trip Voltage VFB Rising l 0.792 0.800 0.808 V VHYST Feedback Comparator Hysteresis l 3 5 7 mV IFB Feedback Pin Current Adjustable Output Version, VFB = 1V –10 0 10 nA ∆VLINEREG Feedback Voltage Line Regulation VIN = 4.5V to 45V 0.001 %/V LTC3631-5, VIN = 6V to 45V Operation VRUN Run Pin Threshold Voltage RUN Rising 1.17 1.21 1.25 V RUN Falling 1.06 1.10 1.14 V Hysteresis 110 mV IRUN Run Pin Leakage Current RUN = 1.3V –10 0 10 nA VHYSTL Hysteresis Pin Voltage Low RUN < 1V, IHYST = 1mA 0.07 0.1 V IHYST Hysteresis Pin Leakage Current VHYST = 1.3V –10 0 10 nA ISS Soft-Start Pin Pull-Up Current VSS < 1.5V 4.5 5.5 6.5 µA tINTSS Internal Soft-Start Time SS Pin Floating 0.75 ms IPEAK Peak Current Trip Threshold ISET Floating l 200 225 280 mA 500k Resistor from ISET to GND 120 mA ISET Shorted to GND 40 50 65 mA RON Power Switch On-Resistance Top Switch ISW = –25mA 3.0 Ω Bottom Switch ISW = 25mA 1.5 Ω Note 1: Stresses beyond those listed under Absolute Maximum Ratings temperature range. Note that the maximum ambient temperature may cause permanent damage to the device. Exposure to any Absolute consistent with these specifications is determined by specific operating Maximum Rating condition for extended periods may affect device conditions in conjunction with board layout, the rated package thermal reliability and lifetime. impedance and other environmental factors. The junction temperature Note 2: The LTC3631 is tested under pulsed load conditions such that (TJ, in °C) is calculated from the ambient temperature (TA, in °C) and power T dissipation (PD, in Watts) according to the formula: J ≈ TA. The LTC3631E is guaranteed to meet specifications from 0°C to 85°C junction temperature. Specifications over the –40°C to TJ = TA + (PD • θJA) 125°C operating junction temperature range are assured by design, where θJA (in °C/W) is the package thermal impedance. characterization and correlation with statistical process controls. The Note 3: Dynamic supply current is higher due to the gate charge being LTC3631I is guaranteed over the full –40°C to 125°C operating junction delivered at the switching frequency. See Applications Information. 3631fe For more information www.linear.com/LTC3631 3 Document Outline Features Description Applications Typical Application Absolute Maximum Ratings Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Application Related Parts