LT1339ISW Linear Technology, LT1339ISW Datasheet
LT1339ISW
Specifications of LT1339ISW
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LT1339ISW Summary of contents
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... The IC also incorporates a soft start feature that is gated by both shutdown and undervoltage lockout conditions. An output phase reversal pin allows flexibility in configu- ration of converter types, including inverting and negative topologies. , LTC and LT are registered trademarks of Linear Technology Corporation DBST 28V IN5819 ...
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... 20mA REF5 U W ORDER PART TOP VIEW NUMBER BOOST LT1339CN LT1339CSW 4 17 12V IN LT1339IN LT1339ISW 6 15 PGND 7 14 PHASE 8 13 RUN/SHDN – SENSE + 10 11 SENSE SW PACKAGE 20-LEAD PLASTIC SO WIDE = 125 C/W ( 125 C/W (SW unless otherwise noted. A MIN TYP MAX ...
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ELECTRICAL C HARA TERISTICS C 12V = V = 12V 2V 0V BOOST C SYMBOL PARAMETER Error Amplifier V Error Amplifier Reference Voltage FB I Feedback Input Current FB g Error Amplifier Transconductance m ...
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LT1339 W U TYPICAL PERFORMANCE CHARACTERISTICS Boost Supply Current vs Temperature 4.0 3.5 3.0 2.5 2.0 1.5 1.0 50 100 125 –50 – TEMPERATURE ( C) 1339 G01 I Shutdown Current vs 12VIN Temperature 190 180 170 ...
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W U TYPICAL PERFORMANCE CHARACTERISTICS Soft Start Charge Current vs Temperature –50 – 100 125 TEMPERATURE ( C) 1339 G10 Bottom Gate Transition Times vs Bottom Gate Capacitance 160 ...
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LT1339 W U TYPICAL PERFORMANCE CHARACTERISTICS UVLO Thresholds vs Temperature 10.00 9.75 RISING 9.50 9.25 9.00 FALLING 8.75 8.50 8.25 8.00 – –50 100 TEMPERATURE ( C) 1339 G18 RUN/SHDN Input Current vs Pin Voltage 800 ...
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PIN FUNCTIONS SYNC (Pin 1): Oscillator Synchronization Pin with TTL- Level Compatible Input. Input drives internal rising edge triggered one-shot; sync signal on/off times should (10 100kHz). Does not contain ...
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LT1339 CTIO AL BLOCK DIAGRA V IN MAIN SWITCH SYNC SWITCH SL/ADJ SENSE R SENSE SENSE V OUT + 0 REF 5V 5V REF REFERENCE RUN/SHDN 1.25V U OPERATION (Refer ...
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U OPERATION (Refer to Functional Block Diagram) The current comparator trip threshold is set on the V which is the output of a transconductance amplifier, or error amplifier (EA). The error amplifier integrates the difference between a feedback voltage (on ...
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LT1339 U U APPLICATIONS INFORMATION R Selection for Output Current SENSE R generates a voltage that is proportional to the SENSE inductor current for use by the LT1339 current sense amplifier. The value based on the required ...
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U U APPLICATIONS INFORMATION impedance of the I pin. The integrator corner fre- AVG quency is typically set orders of magnitude below the oscillator frequency and follows the relation: – (3.2)(10 )/C –3dB AVG ...
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LT1339 U U APPLICATIONS INFORMATION the converter input supply is enabled with no voltage on the LT1339 12V pin, the LT1339 driver output clamps IN will not be activated. To prevent turn-on, an external current path must be used to ...
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U U APPLICATIONS INFORMATION Subharmonic oscillations can be eliminated by augment- ing the increasing ripple current slope (S1) in the control loop. This is accomplished by adding an artificial ramp on the inductor current waveform internal to the IC (with ...
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LT1339 U U APPLICATIONS INFORMATION further increasing the effective compensation slope up to 20% for a given setting. Design Example 20V 15V (DC = 0.75) OUT R = 0.01 SENSE f = 100kHz O L ...
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U U APPLICATIONS INFORMATION In high voltage applications (V > 20V), the topside switch IN is required to slew very large voltages transition losses increase through a square relation, until it becomes the dominant power loss term in ...
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LT1339 U U APPLICATIONS INFORMATION is also small. However, since the FET gate must switch up past the 48V input voltage, transition loss can become a significant factor. In such a case often prudent to take 2 the ...
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U TYPICAL APPLICATIONS LT1339 sn1339 1339fas 17 ...
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LT1339 U TYPICAL APPLICATIONS 18 RTOP RMID COMP GND-S V GND PGND SGND REF V MURS120 SENSE AVG – I SL/ADJ SENSE + CT TS REF 5V TG SYNC BOOST V EFFICIENCY sn1339 1339fas ...
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... DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... Good for Full-Bridge Applications IN Smooth Operation at High Duty Cycle (95% to 100%) Excellent for 50A Drives Synchronous N-Channel MOSFETs Tight 1% Reference High Side Current Sense 60V Input LT/TP 0299 2K REV A • PRINTED IN THE USA LINEAR TECHNOLOGY CORPORATION 1997 sn1339 1339fas ...