ltc1877ems8-trpbf Linear Technology Corporation, ltc1877ems8-trpbf Datasheet
ltc1877ems8-trpbf
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ltc1877ems8-trpbf Summary of contents
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... The LTC1877 is available in a space saving 8-lead MSOP package. Lower input voltage applications (less than 7V abs max) should refer to the LTC1878 data sheet. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation. † V OUT 3 ...
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... RUN 0. < f PLLIN OSC f > f PLLIN OSC I = 100mA –100mA INFORMATION ORDER PART NUMBER 8 PLL LPF 7 SYNC/MODE LTC1877EMS8 MS8 PART MARKING = 150 LTLU MIN TYP MAX 4 30 0.784 0.8 0.816 0.74 0.8 0. 110 0.05 0.15 0.1 0.5 – 0.1 – 0.5 2.65 10 ...
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... IN Note calculated from the ambient temperature T J dissipation P LTC1877EMS8: T Note 4: The LTC1877 is tested in a feedback loop which servos V balance point for the error amplifier (V Note 5: Dynamic supply current is higher due to the gate charge being delivered at the switching frequency. Efficiency vs Output Current ...
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LTC1877 W U TYPICAL PERFORMANCE CHARACTERISTICS Efficiency vs Output Current 3. 10V 7. ...
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W U TYPICAL PERFORMANCE CHARACTERISTICS Switch Leakage vs Temperature 1400 V = 10V IN RUN = 0V 1200 1000 MAIN SWITCH 800 600 400 SYNCHRONOUS SWITCH 200 0 – 100 125 –25 0 TEMPERATURE ( C) 1877 ...
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LTC1877 PIN FUNCTIONS RUN (Pin 1): Run Control Input. Forcing this pin below 0.4V shuts down the LTC1877. In shutdown all functions are disabled drawing <1 A supply current. Forcing this pin above 1.2V enables the LTC1877. ...
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U OPERATIO (Refer to Functional Diagram) Main Control Loop The LTC1877 uses a constant frequency, current mode step-down architecture. Both the main (P-channel MOSFET) and synchronous (N-channel MOSFET) switches are inter- nal. During normal operation, the internal top power MOSFET ...
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LTC1877 U OPERATIO Dropout Operation When the input supply voltage decreases toward the output voltage, the duty cycle increases toward the maxi- mum on-time. Further reduction of the supply voltage forces the main switch to remain on for more than ...
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U U APPLICATIONS INFORMATION V 1 OUT OUT Accepting larger values of I allows the use of low L inductance, but results in higher output voltage ripple and greater core losses. A ...
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LTC1877 U U APPLICATIONS INFORMATION mized to provide stable high performance transient response regardless of the output capacitor selected. ESR is a direct function of the volume of the capacitor. Manufacturers such as Taiyo Yuden, AVX, Sprague, Kemet and Sanyo ...
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U U APPLICATIONS INFORMATION frequency is less than 550kHz, current is sunk continu- ously, pulling down the PLL LPF pin. If the external and internal frequencies are the same but exhibit a phase difference, the current sources turn on for ...
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LTC1877 U U APPLICATIONS INFORMATION Thermal Considerations In most applications the LTC1877 does not dissipate much heat due to its high efficiency. But, in applications where the LTC1877 is running at high ambient tempera- ture with low supply voltage and ...
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U U APPLICATIONS INFORMATION OPTIONAL LTC1877. The power ground traces should be kept short, direct and wide. The signal ground and power ground should converge to a common node in a star- ground configuration. 2. Does the ...
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LTC1877 U U APPLICATIONS INFORMATION 1 RUN 220pF PLL LPF 2 I SYNC/MODE TH LTC1877 GND SW 887k 20pF 412k *SUMIDA CD54-150 **TAIYO YUDEN CERAMIC LMK325BJ106MN ***SANYO POSCAP 6TPA47M Figure 8. Single Lithium-Ion to ...
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... INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE 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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... Secondary Winding OUT from 2.65V to 8. 500mA, 1MHz Operation, OUT Pin, Constant Frequency 600mA, REF OUT up to 36V, Fault Protection 5A, V from 2.2V to 10V OUT 6V 600mA IN Q OUT 1877f LT/TP 1000 4K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2000 ...