LTC1877EMS8#TR Linear Technology, LTC1877EMS8#TR Datasheet
LTC1877EMS8#TR
Specifications of LTC1877EMS8#TR
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LTC1877EMS8#TR Summary of contents
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... MSOP package. Lower input voltage applications (less than 7V abs max) should refer to the LTC1878 data sheet. L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. ...
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... ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC1877EMS8#PBF LTC1877EMS8#TRPBF LTC1877IMS8#PBF LTC1877IMS8#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. Consult LTC Marketing for information on non-standard lead based fi nish parts. ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER I Phase Detector Output Current PLL LPF Sinking Capability Sourcing Capability P-Channel MOSFET PFET DS(ON N-Channel MOSFET NFET DS(ON) I Peak Inductor ...
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LTC1877 TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency vs Output Current 3. 10V 7. 10μ 2.5V ...
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TYPICAL PERFORMANCE CHARACTERISTICS Switch Leakage vs Temperature 1400 V = 10V IN RUN = 0V 1200 1000 MAIN SWITCH 800 600 400 SYNCHRONOUS SWITCH 200 0 –50 – 100 TEMPERATURE (°C) 1877 G12 Start-Up from Shutdown ...
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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 <1μA supply current. Forcing this pin above 1.2V enables the LTC1877. Do not leave RUN ...
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OPERATION (Refer to Functional Diagram) The LTC1877 uses a constant-frequency, current mode step-down architecture. Both the main (P-channel MOS- FET) and synchronous (N-channel MOSFET) switches are internal. During normal operation, the internal top power MOSFET is turned on each cycle ...
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LTC1877 OPERATION Dropout Operation When the input supply voltage decreases toward the output voltage, the duty cycle increases toward the maximum on-time. Further reduction of the supply voltage forces the main switch to remain on for more than one cycle ...
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APPLICATIONS INFORMATION Accepting larger values of ΔI allows the use of low in- L ductance, but results in higher output voltage ripple and greater core losses. A reasonable starting point for setting ripple current is ΔI = 0.4 ...
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LTC1877 APPLICATIONS INFORMATION pacitors. The POSCAP solid electrolytic capacitor available from Sanyo is an excellent choice for output bulk capacitors due to its low ESR/size ratio. Once the ESR requirement for C has been met, the RMS current rating generally ...
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APPLICATIONS INFORMATION this stable operating point the phase comparator output is high impedance and the fi lter capacitor C voltage. The loop fi lter components C and R LP current pulses from the phase detector and provide a stable input ...
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LTC1877 APPLICATIONS INFORMATION temperature of the part. If the junction temperature reaches approximately 150°C, both power switches will be turned off and the SW node will become high impedance. To avoid the LTC1877 from exceeding the maximum junc- tion temperature, ...
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APPLICATIONS INFORMATION Design Example As a design example, assume the LTC1877 is used in a single lithium-ion battery-powered cellular phone applica- tion. The input voltage will be operating from a maximum of 4.2V down to about 2.7V. The load current ...
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LTC1877 TYPICAL APPLICATIONS Dual Lithium-Ion to 2.5V/0.6A Regulator Using All Ceramic Capacitors 1 8 RUN PLL LPF SYNC/MODE TH 220pF LTC1877 GND SW 15μH* *SUMIDA CD54-150 **TAIYO YUDEN CERAMIC ...
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... LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... Low Supply OUT to 500mA, Secondary Winding OUT : 2.65V to 8. 500mA, 1MHz Operation, OUT Pin, Constant Frequency 600mA, REF OUT Up to 36V, Fault Protection 5A 2.2V to 10V OUT 6V 10μ 600mA IN Q OUT LT 0909 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2000 1877fa ...