LTC1266CS Linear Technology, LTC1266CS Datasheet

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... Burst Mode operation, which reduces switching losses. Standby power is re- duced to only 1mW Burst Mode operation are typically 0mA to 500mA. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation. D2 MBR0530T1 ...

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... PWR V < 18V IN 3.5V < PWR V < 18V 2.1V, 3.5V < PWR V < 18V SHDN ORDER PART TOP VIEW NUMBER 16 BDRIVE 15 PGND LTC1266CS 14 LB OUT LTC1266CS-3 LTC1266CS-5 12 SGND LTC1266ACS 11 SHDN LTC1266IS 10 V (NC*) FB LTC1266IS-3 SENSE LTC1266IS-5 S PACKAGE LTC1266AIS = 110 unless otherwise noted. ...

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... Max Leakage Current Into Pin 13 LBIN – < T < (Note 5 10V, unless otherwise noted SYMBOL PARAMETER V Feedback Voltage FB LTC1266AIS LTC1266CS, LTC1266IS V Regulated Output Voltage OUT LTC1266CS-3.3, LTC1266IS-3.3 LTC1266CS-5, LTC1266IS-5 LTC1266-3.3/LTC1266-5 The denotes specifications which apply over the full operating = 10V SHDN BINH CONDITIONS BINH V = 3.3V /2.64 + 25mV (Forced) SENSE – ...

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... LOAD C = 390pF 700mA, I Grade T LOAD Note 5: The LTC1266CS, LTC1266CS-3.3, LTC1266-5 and LTC1266ACS are not tested and not quality assurance sampled at – and 85 C. These specifications are guaranteed by design and/or correlation. The and power A LTC1266IS, LTC1266IS-3.3, LTC1266IS-5 and LTC1266AIS are guaranteed and tested over the – operating temperature range ...

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W U TYPICAL PERFOR A CE CHARACTERISTICS Efficiency vs Input Voltage 100 FIGURE 1 CIRCUIT 2.5A LOAD LOAD 100mA LOAD INPUT ...

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LTC1266 LTC1266-3.3/LTC1266 TYPICAL PERFOR A CE CHARACTERISTICS Off-Time vs Output Voltage 100 – SENSE OUT LTC1266-5 LTC1266-3 OUTPUT VOLTAGE (V) 1266 G10 ...

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CTIO AL DIAGRA V IN SIGNAL GROUND 12 SLEEP + Q S – V – TH2 V TH1 T + OFF-TIME 6 CONTROL OPERATIO The LTC1266 series uses a current mode, constant off- time ...

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LTC1266 LTC1266-3.3/LTC1266-5 U OPERATIO When the voltage on the timing capacitor has discharged past V , comparator T trips, setting the flip-flop. This TH1 causes the bottom-side output to switch off and the topside output to switch on (ground for ...

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U U APPLICATIO S I FOR ATIO R Selection for Output Current SENSE R is chosen based on the required output current. SENSE The LTC1266 series current comparator has a threshold range which extends from a minimum of 25mV/R (when ...

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LTC1266 LTC1266-3.3/LTC1266 APPLICATIO S I FOR ATIO As the operating frequency is increased the gate charge losses will be higher, reducing efficiency (see Efficiency Considerations). The complete expression for operating frequency of the circuit in Figure 1 is ...

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U U APPLICATIO S I FOR ATIO From the duty cycles, the required R MOSFET can be derived: V • DS(ON • I • OUT MAX ...

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LTC1266 LTC1266-3.3/LTC1266 APPLICATIO S I FOR ATIO 1000 0.02 SENSE 800 600 R = 0.02 SENSE 400 200 0.05 SENSE 0 0 ...

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U U APPLICATIO S I FOR ATIO 600 V = 3.3V OUT N-CHANNEL WITH 500 CHARGE PUMP TOPSIDE 400 P-CHANNEL 300 200 TOPSIDE N-CHANNEL WITH POWER V 100 LOAD CURRENT Figure 5. Comparison of Dropout ...

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LTC1266 LTC1266-3.3/LTC1266 APPLICATIO S I FOR ATIO discharge C until the regulator loop adapts to the OUT current change and returns V to its steady-state value. OUT During this recovery time V can be monitored for OUT overshoot ...

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U U APPLICATIO S I FOR ATIO operation, the DC supply current represents the lone (and unavoidable) loss component which continues to become a higher percentage as output current is reduced expected the I R losses dominate at ...

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LTC1266 LTC1266-3.3/LTC1266 APPLICATIO S I FOR ATIO Troubleshooting Hints Since efficiency is critical to LTC1266 series applications very important to verify that the circuit is functioning correctly in both continuous and Burst Mode operation. The waveform ...

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U U APPLICATIO S I FOR ATIO – Are the SENSE and SENSE leads routed together with minimum PC trace spacing? The 1000pF capacitor be- tween Pins 8 and 9 should be as close as possible to the ...

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LTC1266 LTC1266-3.3/LTC1266-5 U TYPICAL APPLICATIO 4.3V TO 10V ( (MIN) LOAD 0.1 F BINH 200pF 3300pF DALE LPT4545-A002 COILTRONICS CTX20-4 ** MMBT2222ALT1 Figure 12. ...

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... Figure 15. All N-Channel 5V to 2.5V/5A High Efficiency Regulator 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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... LTC1735 High Efficiency Synchronous Controller LTC1772 SOT-23 P-Channel Controller LTC1929 42A 2-Phase Synchronous Controller for Single Output No R and OPTI-LOOP are trademarks of Linear Technology Corporation. SENSE Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear-tech.com U Dimensions in inches (millimeters) unless otherwise noted. ...