LTC1149CS#PBF Linear Technology, LTC1149CS#PBF Datasheet
LTC1149CS#PBF
Specifications of LTC1149CS#PBF
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LTC1149CS#PBF Summary of contents
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... Available in 16-Pin Narrow SO Package PPLICATI S Notebook and Palmtop Computers Portable Instruments Battery-Operated Digital Devices Industrial Power Distribution Avionics Systems Telecom Power Supplies , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation TYPICAL PPLICATI 1N4148 V IN CAP PGATE ...
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LTC1149 LTC1149-3.3/LTC1149 BSOLUTE Input Supply Voltage (Pin 2)...................... – 15V to 60V V Output Current (Pin 3) .................................. 50mA CC V Input Voltage (Pin 5)........................................ 16V CC Continuous Output Current (Pins 4, 13) ...
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ELECTRICAL C HARA TERISTICS C SYMBOL PARAMETER V – V Current Sense Threshold Voltage 9 8 LTC1149 LTC1149-3.3 LTC1149-5 V Shutdown 1 Threshold 10 LTC1149-3.3, LTC1149-5 V Shutdown 2 Threshold 15 I Shutdown 2 Input Current Pin ...
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LTC1149 LTC1149-3.3/LTC1149 TYPICAL PERFOR A Efficiency vs Input Voltage 100 FIGURE 1 CIRCUIT LOAD INPUT VOLTAGE (V) 1149 G01 DC Supply Current 3.0 2.5 ACTIVE ...
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CTIO S PGATE (Pin 1): Level-Shifted Gate Drive Signal for Top P-Channel MOSFET. The voltage swing at Pin 1 is from – (Pin 2): Main Supply Input ...
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LTC1149 LTC1149-3.3/LTC1149-5 U OPERATIO (Refer to Functional Diagram) current is made proportional to the output voltage (mea- sured by Pin 8) to model the inductor current, which decays at a rate which is also proportional to the output voltage. While ...
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TEST CIRCUIT + 0 0.047 390pF 3300pF + APPLICATIO S I FOR ATIO Typical Application Circuit The basic LTC1149 series application circuit is shown in Figure 1. External ...
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LTC1149 LTC1149-3.3/LTC1149 APPLICATIO S I FOR ATIO The LTC1149 series automatically extends t short circuit to allow sufficient time for the inductor current to decay between switch cycles. The resulting ripple current causes the average short-circuit current I ...
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U U APPLICATIO S I FOR ATIO Inductor Core Selection Once the minimum value for L is known, the type of inductor must be selected. High efficiency converters generally cannot afford the core loss found in low cost powdered iron ...
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LTC1149 LTC1149-3.3/LTC1149 APPLICATIO S I FOR ATIO the N-channel MOSFET operating in continuous mode are given by: V – OUT N-Ch Duty Cycle = – OUT 2 N- ...
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U U APPLICATIO S I FOR ATIO output ripple at low frequencies will be large enough to trip the voltage comparator. This causes the Burst Mode operation to be activated when the LTC1149 series would normally be in continuous operation. ...
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LTC1149 LTC1149-3.3/LTC1149 APPLICATIO S I FOR ATIO the ground side of the output to prevent the absolute maximum voltage ratings of the sense pins from being exceeded. This is shown in Figure 5. When the current sense comparator ...
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U U APPLICATIO S I FOR ATIO LTC1149 Package Dissipation High input voltage applications in which large MOSFETs are being driven at high frequencies may cause the maxi- mum junction temperature rating for the LTC1149 series to be exceeded. The ...
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LTC1149 LTC1149-3.3/LTC1149 APPLICATIO S I FOR ATIO 25mV minimum current comparator threshold. This tech- nique is also useful for eliminating audible noise from certain types of inductors in high current (I applications when they are lightly loaded. An ...
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U U APPLICATIO S I FOR ATIO 1N4148 0.047 F C 3300pF T 1k 1149 F08 Figure 8. LTC1149 Series Layout Diagram (see Layout Checklist) in series with each sense lead to help decouple Pins 8 and 9. However, when ...
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LTC1149 LTC1149-3.3/LTC1149-5 TYPICAL APPLICATIO S 1N4148 0.068 F 0.047 390pF 3300pF 1k Figure 10. High Efficiency 8V to 20V Input 3.3V/1A Output Regulator 1N4148 0.068 F 0.047 F + 3.3 F 470pF 3300pF 1k Figure 11. ...
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TYPICAL APPLICATIO S 1N4148 0.068 F 0.047 220pF 3300pF 1k Figure 12. Ultra Wide Input Range (5.5V to 25V) High Efficiency 5V Regulator 1N4148 0.068 F 0.047 180pF 3300pF 1k Figure 13. ...
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LTC1149 LTC1149-3.3/LTC1149-5 TYPICAL APPLICATIO 48V 1N4148 0.068 F 0.047 F + 3.3 F 620pF 3300pF 1k Figure 14. High Efficiency 48V Input 5V/2.5A Output Regulator 1N4148 1 PGATE 2 0.068 0.047 ...
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... MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm) 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 representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... OS-CON MBR160 SENSE 20k 0.033 1% OUTPUT GROUND CONNECTION 1149 F17 < 20V IN < 40V SHUTDOWN < 36V, N-Channel Driver IN < 36V, N-Channel Driver IN 1149fa LT/TP 0898 REV A 2K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1993 0.150 – 0.157** (3.810 – 3.988) S16 0695 ...