ltc3221 Linear Technology Corporation, ltc3221 Datasheet
ltc3221
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ltc3221 Summary of contents
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... V of the adjustable LTC3221 can be used to program the desired output voltage. The LTC3221 family is available in a low profi le (0.75mm) 2mm × 2mm 6-pin DFN package. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners ...
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... Lead Free Part Marking: Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. The denotes the specifi cations which apply over the full operating ● = 2.5V (LTC3221-3.3/LTC3221 (LTC3221-5), ⎯ S ⎯ H ⎯ D ⎯ 25° CONDITIONS 1.8V ≤ ...
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... TEMPERATURE (°C) 3221 G04 LTC3221-3.3/LTC3221-5 The denotes the specifi cations which apply over the full operating ● = 2.5V (LTC3221-3.3/LTC3221 (LTC3221-5), ⎯ S ⎯ H ⎯ D ⎯ 25° CONDITIONS = 0V, ⎯ S ⎯ H ⎯ D ⎯ OUT ⎯ S ⎯ H ⎯ D ⎯ ⎯ ...
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... 0.1 0.01 0.001 0.01 0 LOAD CURRENT (mA) Output Ripple V OUT 20mV/DIV (AC-COUPLED) 1µs/DIV 60mA LOAD C = 4.7µF, 6.3V, SIZE 0603 OUT (LTC3221-3.3 only) Effective Open-Loop Output Resistance vs Temperature 1. OUT 3.5 –50 – TEMPERATURE (°C) 3221 G08 Effi ...
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... IN 1 0.1 0.01 0.001 4.5 0.01 0 LOAD CURRENT (mA) Output Ripple V OUT 50mV/DIV (AC-COUPLED) 1µs/DIV 60mA LOAD C = 4.7µF, 6.3V, SIZE 0603 OUT LTC3221/ (LTC3221-5 only) Effective Open-Loop Output Resistance vs Temperature 2. 4.5V 14 OUT 4.2 –50 – TEMPERATURE (°C) 3221 G17 Effi ...
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... C– (Pin 2): Flying Capacitor Negative Terminal. ⎯ S ⎯ H ⎯ D ⎯ N (Pin 3) (LTC3221-3.3/LTC3221-5): Active Low Shutdown Input. A low on ⎯ S ⎯ H ⎯ D ⎯ N disables the LTC3221-3.3/ LTC3221-5. ⎯ S ⎯ H ⎯ D ⎯ N must not be allowed to fl oat. FB (Pin 3) (LTC3221): Feedback. The voltage on this pin is compared to the internal reference voltage (1 ...
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... U OPERATIO (Refer to Block Diagrams) The LTC3221 has a FB pin in place of the ⎯ S ⎯ H ⎯ D ⎯ N pin. This allows the output voltage to be programmed using an external resistive divider. Burst Mode Operation The LTC3221 family regulates the output voltage throughout the full 60mA load range using Burst Mode control. This keeps the quiescent current low at light load and improves the effi ...
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... OUT The style and value of capacitors used with the LTC3221 family determine several important parameters such as output ripple, charge pump strength and minimum start- up time. 75 100 ...
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... C FLY grammable LTC3221 may be set to an arbitrary voltage via an external resistive divider. Figure 3 shows the required FLY voltage divider connection. Figure 3. Programming the Adjustable LTC3221 The voltage divider ratio is given by the expression: ...
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... This can be achieved from a printed circuit board layout 3221 F04 with a solid ground plane and a good connection to the ground pins of the LTC3221 and the Exposed Pad of the DFN package. Operation out of this curve will cause the junction temperature to exceed 150°C which is the maxi- mum junction temperature allowed. – ...
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... DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE LTC3221/ LTC3221-3.3/LTC3221 0.115 0.38 ± 0.05 TYP 4 6 0.56 ± ...
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