LTC1435AC LINER [Linear Technology], LTC1435AC Datasheet
LTC1435AC
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LTC1435AC Summary of contents
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FEATURES Dual N-Channel MOSFET Synchronous Drive Programmable Fixed Frequency Wide V Range: 3.5V to 36V Operation IN Low Minimum On-Time ( 300ns) for High Frequency, Low Duty Cycle Applications Very Low Dropout Operation: 99% Duty Cycle Low Standby Current Secondary ...
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... SFB, Run/SS Voltages .............................. 10V to – 0.3V Peak Driver Output Current < (TG, BG) ............. 2A INTV Output Current ........................................ 50mA CC Operating Ambient Temperature Range LTC1435AC ............................................ LTC1435AI ......................................... – Junction Temperature (Note 1)............................. 125 C Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C ELECTRICAL CHARACTERISTICS ...
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... ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER Oscillator f Oscillator Frequency OSC The denotes specifications which apply over the full operating temperature range. LTC1435ACG/LTC1435ACS LTC1435AIG/LTC1435AIS: – Note calculated from the ambient temperature T J dissipation P according to the following formula: ...
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LTC1435A W U TYPICAL PERFORMANCE CHARACTERISTICS Input Supply and Shutdown Current vs Input Voltage 2.5 2 OUT 1.5 EXTV = V CC OUT V = 3.3V 1.0 OUT EXTV = OPEN CC 0.5 SHUTDOWN ...
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W U TYPICAL PERFORMANCE CHARACTERISTICS Burst Mode Operation V OUT 20mV/DIV V ITH 200mV/DIV I = 50mA LOAD PIN FUNCTIONS C (Pin 1): External capacitor C OSC ground sets the operating frequency. RUN/SS (Pin 2): Combination of ...
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LTC1435A U U FUNCTIONAL DIAGRA 1 OSC + OV – 1.28V V OSENSE V FB – 1.19V 180k m SHUTDOWN RUN 30k SOFT START RUN/SS 3 ...
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U OPERATION (Refer to Functional Diagram) on and periodically forces a brief off period to allow C recharge. The main control loop is shut down by pulling the RUN/SS pin low. Releasing RUN/SS allows an internal 3 A current source ...
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LTC1435A U U APPLICATIONS INFORMATION The value calculated from the desired operating OSC frequency: 4 1.37( OSC Frequency (kHz) A graph for selecting C vs frequency is given in Figure OSC 2. ...
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U U APPLICATIONS INFORMATION a fixed inductor value, but it is very dependent on induc- tance selected. As inductance increases, core losses go down. Unfortunately, increased inductance requires more turns of wire and therefore copper losses will increase. Ferrite designs ...
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LTC1435A U U APPLICATIONS INFORMATION C and C Selection IN OUT In continuous mode, the source current of the top N-channel MOSFET is a square wave of duty cycle prevent large voltage transients, a low ESR ...
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U U APPLICATIONS INFORMATION control power to be derived from the output during normal operation (4.8V < V < 9V) and from the internal regu- OUT lator when the output is out of regulation (start-up, short circuit). Do not apply ...
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LTC1435A APPLICATIONS INFORMATION The external resistive divider is connected to the output as shown in Figure 5 allowing remote voltage sensing. 1.19V V OSENSE 100pF LTC1435A SGND 1435A F05 Figure 5. Setting the LTC1435A Output Voltage Run/ ...
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U U APPLICATIONS INFORMATION on and off again determined by internal timing delays and the gate charge required to turn on the top MOSFET. Low duty cycle applications may approach this minimum on-time limit. If the duty cycle ...
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LTC1435A U U APPLICATIONS INFORMATION By powering EXTV from an output-derived source, the CC additional V current resulting from the driver and IN control currents will be scaled by a factor of Duty Cycle/Efficiency. For example 20V to ...
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U U APPLICATIONS INFORMATION conduct during double battery operation, but must still clamp the input voltage below breakdown of the converter. Although the LTC1435A has a maximum input voltage of 36V, most applications will be limited to 30V by the ...
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LTC1435A U U APPLICATIONS INFORMATION 4. Does the (+) plate of C connect to the drain of the IN topside MOSFET(s) as closely as possible? This capaci- tor provides the AC current to the MOSFET(s the INTV decoupling ...
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U TYPICAL APPLICATIONS C OSC 68pF 1 C OSC RUN/ 10k 470pF 51pF 4 SFB LTC1435A 5 SGND 100pF 6 V OSENSE 7 – SENSE 1000pF ...
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LTC1435A U TYPICAL APPLICATIONS Constant-Current/Constant-Voltage High Efficiency Battery Charger C1* C2 1.5M 35V 35V E3 GND E3 SHDN C12 C13 R5 0.1 F 0.033 F 1k C14 1000pF C15 LT1620 ...
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U TYPICAL APPLICATIONS C OSC 68pF 1 C OSC RUN/ 10k 510pF 51pF 4 SFB 5 SGND 100pF 6 V OSENSE 7 – SENSE 1000pF 8 ...
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LTC1435A U TYPICAL APPLICATION C OSC 68pF 1 C OSC RUN/ 10k 330pF 51pF 4 SFB INTV CC LTC1435A 5 SGND 100pF 6 V OSENSE 7 ...