ltc3824 Linear Technology Corporation, ltc3824 Datasheet
ltc3824
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ltc3824 Summary of contents
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... Other features include current limit, soft start, micropower shutdown, and burst mode disable. The LTC3824 is available in a 10-lead MSE power package. L, LT, LTC, LTM and Burst Mode are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 5731964. 22μ ...
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... C SYNC/MODE ...............................................................6V V – V ..............................................................1V CC SENSE Maximum Temperatures (Note 2) LTC3824E ................................................. –40°C to 85°C LTC3824I ................................................ –40°C to 125°C Storage Temperature Range ..................... –65° to 150°C Lead Temperature (Soldering, 10 sec) .................. 300°C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC3824EMSE#PBF LTC3824EMSE#TRPBF ...
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... C = 10nF GATE Note 2: The LTC3824E is guaranteed to meet performance specifi cations from 0°C to 85°C junction temperature. Specifi cations over the –40°C to 85°C temperature range are assured by design characterization and correlation with statistical process controls. The LTC3824I grade is guaranteed over the full – ...
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... LTC3824 TYPICAL PERFORMANCE CHARACTERISTICS ( Low CC CAP GATE DRIVE 8.5 8.4 8.3 8.2 8.1 8.0 7.9 7.8 7.7 7 (mA) GATE V Change vs V REF CC 0.4 0.2 0 –0.2 –0 (V) CC 3824 G04 Burst Mode Disabled 200mA, V LOAD I = 200mA LOAD V OUT 10mV/DIV INDUCTOR CURRENT 1A/DIV 4μs/DIV ...
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... Burst Mode operation is one third of current limit. If this pin is grounded or the synchronization pulse is present with a frequency greater than 20kHz then Burst Mode operation is disabled and the LTC3824 goes into pulse skipping at light loads. To synchronize the LTC3824, the duty cycle of the synchronizing pulse can range from 10% to 70% and the synchronizing frequency has to be higher than the programmed frequency ...
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... Burst Mode OPERATION CONTROL APPLICATIONS INFORMATION Operation The LTC3824 is a constant frequency current mode buck controller with programmable switching frequency up to 600kHz. Referring to the Block Diagram, the LTC3824’s basic functions include a transconductance amplifi regulate the output voltage and control the current mode ...
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... APPLICATIONS INFORMATION Burst Mode Operation The LTC3824 can be confi gured for Burst Mode operation to enhance light load effi ciency (only 40μA quiescent current) and extend battery run time by leaving the SYNC/MODE pin open or pulling it higher than 2V. In this mode, when ...
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... R of the MOSFET listed in the data sheet. DS(ON) 8 The power dissipated by the MOSFET when the LTC3824 is in continuous mode is given MOSFET The fi rst term in the equation represents the I the device and the second term is the switching losses. K (estimated as 1. empirical factor inversely related to the gate drive current and has the unit of 1/Amps. The δ ...
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... V throughout the external bypass capacitor The resulting dQ/ current that must be supplied to the capacitor by the internal regulator 1mA + f • LTC3824 increases with input voltage. Multiple capacitors . The V current is the sum transferred from the CAP pin • I ...
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... A 100pF capacitor is required across the V noise fi ltering and should be placed as close to the pins as possible. Design Example As an example, the LTC3824 is designed for an automotive 5V power supply with the following specifi cations: ESR dissipation OUT Maximum I 60V briefl ...
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... REF 0.18 (.007) 0.127 ± 0.076 (.005 ± .003) 4. DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS. INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.152mm (.006") PER SIDE 5. LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX LTC3824 V 12V OUT OUT 270μF 1μ ...
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... TDK C4532X7R2A225M C IN2 CAP C : SANYO OSCON, 16SP270M, TDKC2012X7RIC105K 0.1μF OUT L1: D104C919AS-330M D1: SS3H9 CAP Q1: Si7465DP 100pF SENSE S 0.025Ω LTC3824 GATE Q1 L1 33μH 100pF D1 51Ω 15k 1000pF COMMENTS 3.5V ≤ V ≤ 36V; N-Channel MOSFET 3.3V ≤ V ≤ 60V; 1.5A Peak Switch Current IN 4V ≤ ...