LT1339I LINER [Linear Technology], LT1339I Datasheet
LT1339I
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LT1339I Summary of contents
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FEATURES High Voltage: Operation Up to 60V High Current: Dual N-Channel Synchronous Drive Handles Up to 10,000pF Gate Capacitance Programmable Average Load Current Limiting 5V Reference Output with 10mA External Loading Capability Programmable Fixed Frequency Synchronizable Current Mode Operation Up ...
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... RUN/SHDN Pin Voltage ...................... – 0.3V to 12V All Other Inputs .......................................– 0. Maximum Currents 5V Reference Output Current............................ 65mA Maximum Temperatures Operating Ambient Temperature Range LT1339C............................................. LT1339I ......................................... – Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C ELECTRICAL C HARA TERISTICS C 12V ...
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... SENSE – SENSE = 5mV Sink (V > 5V) CMSENSE Source (V = 0V) CMSENSE f 150kHz O LT1339C LT1339I Rising Edge f 150kHz SYNC 12V < 0.5V RUN Note 2: Supply current specification does not include external FET gate charge currents. Actual supply currents will be higher and vary with operating frequency, operating voltages and the type of external FETs used ...
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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 U U FUNCTIONAL BLOCK DIAGRA MAIN SWITCH SYNC SWITCH SL/ADJ + SENSE R SENSE – SENSE V OUT + 0 REF 1.25V 5V 5V REF REFERENCE RUN/SHDN 1.25V U ...
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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 OUT IN OUT L MIN where f = operating frequency. Given an inductor value O (L), the peak inductor current is the sum of the average inductor ...
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U U APPLICATIONS INFORMATION OSCILLATOR PERIOD 0 TIME a Figure 5. Inductor Current at DC > 50% and Slope Compensation Adjusted Signal For duty cycles less than 50% (DC < 0.5), S ...
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LT1339 U U APPLICATIONS INFORMATION MIN 0 084 100000 Since less than L , additional slope compen- MIN sation is necessary. The total slope compensation required is: ...
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U U APPLICATIONS INFORMATION The maximum power loss terms for the switches are thus (DC)( )(R MAIN MAX DS(ON )(C )(f IN MAX RSS – ...
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LT1339 U U APPLICATIONS INFORMATION switch gates load the driver outputs such that rise/fall times exceed about 100ns, buffers can sometimes result in efficiency gains. Buffers also reduce the effect of back injection into the bottom side driver output due ...
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U TYPICAL APPLICATIONS LT1339 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 ...
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U TYPICAL APPLICATIONS 5V to 28V DC/DC Synchronous Boost Converter Limits Input Current at 60A (DC 10k + C 5VREF AVG 2200pF 2200pF 1500pF VC ...
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LT1339 U TYPICAL APPLICATION 48V to 5V 50A DC/DC Converter with Input Supply Start-Up Protection SYNC R CT 10k 5V REF 5VREF 2200pF SL/ADJ C , 2200pF AVG I AVG ...