Datasheet LT3991, LT3991-3.3, LT3991-5 (Analog Devices) - 3

LT3991/LT3991-3.3/LT3991-5
elecTrical characTerisTics The
l
denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN = 12V, VEN = 12V, VBD = 3.3V unless otherwise noted. (Note 2) PARAMETER CONDITIONS MIN TYP MAX UNITS
Minimum Input Voltage (Note 4) l 4 4.3 V Quiescent Current from VIN VEN Low 0.7 1.2 μA VEN High, VSYNC Low 1.7 2.7 μA VEN High, VSYNC Low l 4.5 μA LT3991 FB Pin Current VFB = 1.19V l 0.1 12 nA Internal Feedback Resistor Divider 10 MΩ Feedback Voltage 1.175 1.19 1.205 V l 1.165 1.19 1.215 V LT3991-3.3 Output Voltage 3.25 3.3 3.35 V l 3.224 3.3 3.376 V LT3991-5 Output Voltage 4.93 5 5.07 V l 4.89 5 5.11 V FB Voltage Line Regulation 4.3V < VIN < 40V (Note 4) 0.0002 0.01 %/V Switching Frequency RT = 11k 1.6 2 2.4 MHz RT = 35.7k 0.8 1 1.2 MHz RT = 255k 160 200 240 kHz Minimum Switch On Time 110 ns Minimum Switch Off Time 150 200 ns Switch Current Limit 1.7 2.3 2.9 A Switch VCESAT ISW = 1A 440 mV Switch Leakage Current 0.02 1 μA Boost Schottky Forward Voltage ISH = 100mA 800 mV Boost Schottky Reverse Leakage VREVERSE = 12V 0.02 1 μA Minimum Boost Voltage (Note 3) VIN = 5V l 1.4 1.8 V BOOST Pin Current ISW = 1A, VBOOST = 15V 25 33 mA EN Voltage Threshold EN Rising l 0.95 1.01 1.07 V EN Voltage Hysteresis 30 mV EN Pin Current 0.2 20 nA LT3991 PG Threshold Offset from VFB VFB Rising 60 100 140 mV LT3991 PG Hysteresis 20 mV LT3991-X PG Threshold Offset from VOUT VOUT Rising 5.5 9 12.5 % LT3991X PG Hysteresis 1.3 % PG Leakage VPG = 3V 0.02 1 µA PG Sink Current VPG = 0.4V l 300 570 μA SYNC Threshold 0.6 0.8 1.0 V SYNC Pin Current 0.1 nA SS Source Current VSS = 1V 0.6 1 1.6 μA
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings The LT3991I is guaranteed over the full –40°C to 125°C operating junction may cause permanent damage to the device. Exposure to any Absolute temperature range. High junction temperatures degrade operating Maximum Rating condition for extended periods may affect device lifetimes. Operating lifetime is derated at junction temperatures greater reliability and lifetime. than 125°C.
Note 2:
The LT3991E is guaranteed to meet performance specifications
Note 3:
This is the minimum voltage across the boost capacitor needed to from 0°C to 125°C junction temperature. Specifications over the –40°C guarantee full saturation of the switch. to 125°C operating junction temperature range are assured by design,
Note 4:
Minimum input voltage depends on application circuit. characterization, and correlation with statistical process controls. 3991fa 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 Revision History Related Parts