Datasheet LT3976 (Analog Devices) - 3

LT3976
e lecTrical characTerisTics The
l
denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Note 2) PARAMETER CONDITIONS MIN TYP MAX UNITS
Minimum Input Voltage (Note 3) l 4 4.3 V Dropout Comparator Threshold (VIN – OUT) Falling 430 500 570 mV Dropout Comparator Threshold Hysteresis 25 mV Quiescent Current from VIN VEN Low 0.7 1.3 µA VEN High, VSYNC Low 1.6 2.7 µA VEN High, VSYNC Low l 30 µA FB Pin Current VFB = 1.5V l 0.1 12 nA Feedback Voltage 1.183 1.197 1.212 V l 1.173 1.197 1.222 V FB Voltage Line Regulation 4.3V < VIN < 40V (Note 3) 0.0003 0.01 %/V Switching Frequency RT = 11.8k 1.8 2.25 2.7 MHz RT = 41.2k 0.8 1 1.2 MHz RT = 294k 160 200 240 kHz Minimum Switch On-Time 120 ns Minimum Switch Off-Time (Note 4) 150 200 ns Switch Current Limit VFB = 1V 7.5 10 12.5 A Foldback Switch Current Limit VFB = 0V 4.8 A Switch VCESAT ISW = 1A 80 mV Switch Leakage Current 0.02 1 μA Boost Schottky Forward Voltage ISH = 100mA 730 mV Boost Schottky Reverse Leakage VREVERSE = 12V 0.02 2 μA Minimum Boost Voltage (Note 5) l 1.3 1.8 V BOOST Pin Current ISW = 1A, VBOOST – VSW = 3V 20 32 mA EN Voltage Threshold EN Falling, VIN ≥ 4.3V l 0.92 1.02 1.12 V EN Voltage Hysteresis 60 mV EN Pin Current 0.2 20 nA PG Threshold Offset from VFB VFB Falling 5 8.4 13 % PG Hysteresis as % of Output Voltage 1.7 % PG Leakage VPG = 3V 0.02 1 µA PG Sink Current VPG = 0.4V l 125 480 μA SYNC Low Threshold 0.6 1.0 V SYNC High Threshold 1.18 1.5 V SYNC Pin Current VSYNC = 6V 0.1 nA SS Source Current VSS = 0.5V 0.9 1.8 2.6 μA
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings temperature range. The LT3976H is guaranteed over the full –40°C to may cause permanent damage to the device. Exposure to any Absolute 150°C operating junction temperature range. High junction temperatures Maximum Rating condition for extended periods may affect device degrade operating lifetimes. Operating lifetime is derated at junction reliability and lifetime. temperatures greater than 125°C. The junction temperature (TJ, in °C) is
Note 2:
The LT3976E is guaranteed to meet performance specifications calculated from the ambient temperature (TA, in °C) and power dissipation from 0°C to 125°C junction temperature. Specifications over the –40°C (PD, in Watts) according to the formula: to 125°C operating junction temperature range are assured by design, TJ = TA + (PD • θJA) characterization, and correlation with statistical process controls. The where θJA (in °C/W) is the package thermal impedance. LT3976I is guaranteed over the full –40°C to 125°C operating junction 3976f For more information www.linear.com/3976 3 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Typical Application Related Parts