LTC3633 LINER [Linear Technology], LTC3633 Datasheet
LTC3633
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LTC3633 Summary of contents
Page 1
... The LTC3633 can select between forced continuous mode and high effi ciency Burst Mode operation. L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation ...
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... LTC3633EUFD#TRPBF LTC3633IUFD#PBF LTC3633IUFD#TRPBF LTC3633EFE#PBF LTC3633EFE#TRPBF LTC3633IFE#PBF LTC3633IFE#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. For more information on lead free part marking, go to: For more information on tape and reel specifi ...
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... Load IN 0mA to 50mA Load 15V 15V 0mA to 10mA LOAD V Rising FB V Falling FB V Falling FB V Rising FB 10mA Load TRACKSS = 0.3V PHMODE V IH PHMODE V IL LTC3633 = 3.3V, unless otherwise noted. CC MIN TYP MAX l 3.6 15 1.3 500 13 l 0.594 0.6 0.606 0.02 0.05 ±30 1 1.4 2 2.6 1.7 2 2.3 3 ...
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... Note 2: Guaranteed by long term current density limitations. Note 3: The LTC3633E is guaranteed to meet specifi ed performance from 0°C to 85°C. Specifi cations over the –40°C to 125°C operating junction temperature range are assured by design, characterization and correlation with statistical process controls ...
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... INPUT VOLTAGE (V) Oscillator Frequency vs Temperature –2 –4 –6 –8 –10 3 –50 – TEMPERATURE (°C) LTC3633 T = 25° 12V 1MHz 1μH unless Effi ciency vs Load Current 100 Burst Mode 90 OPERATION 80 FORCED 70 CONTINUOUS OPERATION ...
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... LTC3633 TYPICAL PERFORMANCE CHARACTERISTICS otherwise noted. Internal MOSFET R DS(ON) vs Temperature 160 TOP SWITCH 140 120 100 80 BOTTOM SWITCH –50 – 100 TEMPERATURE (°C) 3633 G10 Switch Leakage vs Temperature 7000 MAIN SWITCH SYNCHRONOUS SWITCH 6000 5000 4000 3000 ...
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... G19 400μs/DIV C = 4.7nF 150mA LOAD RUN 2V/DIV V 1.8V OUT 1V/DIV I 2A/DIV 3633 G22 LTC3633 T = 25° 12V 1MHz 1μH unless Start-Up (Forced Continuous Mode) RUN 2V/DIV V OUT 1V/DIV I L 1A/DIV 3633 G20 400μs/DIV ...
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... Input Pin for Channel 2. Forcing a voltage below 0.6V on this pin bypasses the internal reference input to the error amplifi er. The LTC3633 will servo the FB pin to the TRACK voltage under this condition. Above 0.6V, the tracking func- tion stops and the internal reference resumes control of the error amplifi ...
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... Input Pin for Channel 1. Forcing a voltage below 0.6V on this pin bypasses the internal reference input to the error amplifi er. The LTC3633 will servo the FB pin to the TRACK voltage. Above 0.6V, the tracking function stops and the internal reference resumes control of the error amplifi er. ...
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... LTC3633 BLOCK DIAGRAM OSC1 CONTROLLER COMP SELECT ITH – 0V PGOOD + – CHANNEL 1 OSC1 RT OSC OSC PLL-SYNC R RT PHMODE PHASE SELECT OSC2 CHANNEL 2 (SAME AS CHANNEL 180k + 0.72V VON ION S Q SWITCH ...
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... This condition is released once regulation within a ±5% window is achieved. To prevent unwanted PGOOD glitches during transients or dynamic V LTC3633 PGOOD falling edge includes a fi lter time of ap- proximately 40μs. V Overvoltage Protection trips, thus restarting ...
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... LTC3633 APPLICATIONS INFORMATION A general LTC3633 application circuit is shown on the fi rst page of this data sheet. External component selection is largely driven by the load requirement and switching frequency. Component selection typically begins with the selection of the inductor L and resistor R inductor is chosen, the input capacitor, C put capacitor can be selected ...
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... Even though the LTC3633 design includes an overvoltage protection circuit, care must always be taken to ensure input voltage transients do not pose an overvoltage hazard to the part. 5.2 × 5.5 ...
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... LTC3633. This supply is intended only to supply ad- ditional DC load currents as desired and not intended to regulate large transient or AC behavior, as this may impact LTC3633 operation. Boost Capacitor should be The LTC3633 uses a “bootstrap” circuit to create a voltage DROOP rail above the applied input voltage V capacitor, C BOOST equal to INTV CC turned on ...
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... Internal/External Loop Compensation The LTC3633 provides the option to use a fi xed internal loop compensation network to reduce both the required external component count and design time. The internal loop compensation network can be selected by connec- ...
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... F response, as previously shown in Figure 2. Capacitor C provides phase lead by creating a high frequency zero with R2 which improves the phase margin. ITH R COMP 13k LTC3633 C 220pF SGND 3633 F03 Figure 3. Compensation Component Checking Transient Response The regulator loop response can be checked by observing the response of the system to a load step. When confi gured ...
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... MODE/SYNC pin is tied to ground, forced continuous mode operation is selected, creating the lowest fi xed output ripple at the expense of light load effi ciency. The LTC3633 will detect the presence of the external clock signal on the MODE/SYNC pin and synchronize the internal oscillator to the phase and frequency of the incoming clock ...
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... TRACKSS pin accuracy. Output Power Good The PGOOD output of the LTC3633 is driven by a 15Ω (typical) open-drain pull-down device. This device will be turned off once the output voltage is within 5% (typical) of the target regulation point, allowing the voltage at PGOOD to rise via an external pull-up resistor ...
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... This gives the QFN and TSSOP packages exceptional thermal properties, which are necessary to prevent excessive self-heating of the part in normal operation majority of applications, the LTC3633 does not dis- sipate much heat due to its high effi ciency and low thermal rail. CC resistance of its exposed-back QFN package ...
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... LTC3633 APPLICATIONS INFORMATION is to determine whether the power dissipated exceeds the maximum junction temperature of the part. The tempera- ture rise is given by • θ RISE example, consider the case when one of the regula- tors is used in an application where V frequency = 2MHz ...
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... These copper areas should be connected to the exposed backside of the package (PGND). Refer to Figures 9 and 10 for board layout examples. Design Example As a design example, consider using the LTC3633 in an application with the following specifi cations 13.2V, V and PGND I ...
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... 12.1k, R2 and R4 are calculated to be (12.1k) • (12.1k) • The fi nal circuit is shown in Figure 8. input with IN2 IN1 RUN1 INTV CC RUN2 ITH1 ITH2 LTC3633 V2P5 MODE/SYNC RT PHMODE TRACKSS2 TRACKSS1 PGOOD2 PGOOD1 BOOST2 BOOST1 0.1μF SW2 SW1 V V ON2 ON1 V V ...
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... VIA TO V AND R2 (NOT SHOWN) ON1 C OUT1 VIAS TO GROUND PLANE GND VIA TO BOOST1 SW1 C BOOST1 C BOOST2 SW2 VIA TO BOOST2 GND VIAS TO GROUND PLANE C OUT2 VIA TO V AND R4 (NOT SHOWN) ON2 LTC3633 3633 F09 V OUT1 OUT2 3633 F10 23 3633f ...
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... V ON2 ON1 V V FB2 FB1 SGND PGND R4 R3 31.6k 10k R6 100k V V IN2 IN1 RUN1 INTV CC PGOOD2 ITH1 RUN2 ITH2 LTC3633 V2P5 MODE/SYNC PHMODE RT BOOST2 BOOST1 0.1μF SW2 SW1 V V ON2 ON1 V V FB2 FB1 SGND PGND R3 12.1k C2 2.2μF 6.98k 10pF 220pF L1 0.1μ ...
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... IN2 IN1 RUN1 INTV CC RUN2 ITH1 ITH2 MODE/SYNC V2P5 LTC3633 PHMODE RT TRACKSS2 BOOST2 BOOST1 SW2 SW1 V V ON2 ON1 V V FB2 FB1 SGND PGND R3 R1 10k 10k LTC3633 C2 2.2μF L1 0.1μF 0.68μH V OUT1 1. OUT1 4.99k 15k 47μF 3633 TA03 3633f 25 ...
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... LTC3633 PACKAGE DESCRIPTION 4.75 (.187) 6.60 ±0.10 4.50 ±0.10 SEE NOTE 4 RECOMMENDED SOLDER PAD LAYOUT 4.30 – 4.50* (.169 – .177) 0.09 – 0.20 (.0035 – .0079) (.020 – .030) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS 2. DIMENSIONS ARE IN MILLIMETERS (INCHES) 3. DRAWING NOT TO SCALE 26 FE Package 28-Lead Plastic TSSOP (4.4mm) (Reference LTC DWG # 05-08-1663) ...
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... Plastic QFN (4mm × 5mm) (Reference LTC DWG # 05-08-1712 Rev B) 0.70 ±0.05 3.65 ± 0.05 PACKAGE OUTLINE 3.50 REF 4.10 ± 0.05 5.50 ± 0.05 0.75 ± 0.05 4.00 ± 0.10 (2 SIDES) 3.50 REF 0.200 REF 0.00 – 0.05 LTC3633 PIN 1 NOTCH 2.50 REF R = 0. 0.115 × 45° CHAMFER TYP TYP 27 28 0.40 ± 0. 3.65 ± 0.10 2.65 ± ...
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... McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 3.3V/1.8V Buck Regulator with 2.5V LDO Output V V IN2 IN1 RUN1 INTV CC RUN2 ITH1 ITH2 PHMODE MODE/SYNC LTC3633 RT V2P5 BOOST2 BOOST1 0.1μF SW2 SW1 V V ON2 ON1 V V FB2 FB1 SGND PGND ...