LTC3604 Linear Technology, LTC3604 Datasheet
LTC3604
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LTC3604 Summary of contents
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... The LTC3604 offers two operational modes: Burst Mode operation and forced continuous mode to allow the user to optimize output voltage ripple, noise, and light load effi ...
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... LTC3604EUD#PBF LTC3604EUD#TRPBF LTC3604IUD#PBF LTC3604IUD#TRPBF LTC3604EMSE#PBF LTC3604EMSE#TRPBF LTC3604IMSE#PBF LTC3604IMSE#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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... Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC3604E is guaranteed to meet performance specifi cations from 0°C to 85°C. Specifi cations over the –40°C to 125°C operating l The denotes the specifi ...
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... Note 4: Maximum allowed current draw when used as a regulated output is 5mA. This supply is only intended to provide additional DC load current as needed and not intended to regulate large transient or ac behavior as these waveforms may impact LTC3604 operation. TYPICAL PERFORMANCE CHARACTERISTICS T = 25° 12V 1MHz 1.5μ ...
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... Temperature 2. INTV CC 2.50 2.25 2.00 1.75 1.50 1.25 125 –50 – TEMPERATURE (°C) 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 –0.2 100 125 150 3604 G13 LTC3604 www.DataSheet4U.com Quiescent Current vs Supply Voltage 380 340 300 260 220 100 125 SUPPLY VOLTAGE (V) 3604 G08 TRACK Pull-Up Current vs Temperature 2.0 1.8 1.6 1.4 1.2 1.0 0.8 0.6 100 125 50 –50 – ...
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... LTC3604 TYPICAL PERFORMANCE CHARACTERISTICS T = 25° 12V 1MHz 1.5μH unless otherwise noted Output Ripple Voltage Burst Mode Operation SW 5V/DIV V OUT 20mV/DIV AC-COUPLED I L 1A/DIV V = 12V 2μs/DIV 1.8V OUT I = 180mA LOAD Start-Up from Shutdown Burst Mode Operation RUN 2V/DIV PGOOD ...
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... Soft-Start Input Pin. Forcing a voltage below 0.6V on this pin overrides the internal reference input to the error amplifi er. The LTC3604 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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... LTC3604 FUNCTIONAL BLOCK DIAGRAM 0.72V 180k CONTROLLER VON ION RT OSC CMP – MODE/SYNC OSC PLL-SYNC THB – 0.6V REF INTERNAL SOFT-START SWITCH LOGIC ON AND 15k + ANTI- SHOOT I REV THROUGH – RUN ...
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... At low load currents the inductor current can drop to zero or become negative. If the LTC3604 is confi gured for Burst Mode operation, this inductor current condition is detected by the current reversal comparator turn shuts off the bottom power MOSFET and places the part into a low quiescent current sleep state resulting in discontinuous operation and increased effi ...
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... LTC3604 APPLICATIONS INFORMATION A general LTC3604 application circuit is shown on the fi rst page of this data sheet. External component selection is largely driven by the load requirement and begins with the selection of the inductor L. Once the inductor is chosen, the input capacitor the output capacitor ...
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... Several capacitors may be paralleled to meet the require- ments of the design. For low input voltage applications suffi cient bulk input capacitance is needed to minimize transient effects during output load changes. Even though the LTC3604 design includes an overvoltage protection 5.2 × 5.5 2 circuit, care must always be taken to ensure input voltage transients do not pose an overvoltage hazard to the part ...
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... When the top MOSFET is turned on, the BOOST pin voltage will be equal to approximately V 3.3V. For most applications a 0.1μF ceramic capacitor will provide adequate performance. Output Voltage Programming The LTC3604 will adjust the output voltage such that V equals the reference voltage of 0.6V according to: ⎛ ⎞ R ...
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... Selection show, high switching frequencies allow the use of smaller board components, thus reducing the footprint of the application circuit. Internal/External Loop Compensation The LTC3604 provides the option to use a fi xed internal loop compensation network to reduce both the required is the external component count and design time. The internal ...
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... OUT Output Voltage Tracking and Soft-Start The LTC3604 allows the user to control the output voltage ramp rate by means of the TRACK/SS pin. From 0V to 0.6V the TRACK/SS pin will override the internal reference input to the error amplifi er forcing regulation of the feedback voltage to that seen at the TRACK/SS pin ...
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... Mode operation to prevent inductor saturation and improve TRACK/SS pin accuracy. Output Power Good The PGOOD output of the LTC3604 is driven by a 15Ω (typical) open-drain pull-down device. This device will be turned off once the output voltage is within ±5% (typi- cal) of the target regulation point allowing the voltage at PGOOD to rise via an external pull-up resistor (100k typi- cal). If the output voltage exits a ± ...
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... In many applications, the LTC3604 does not dissipate much heat due to its high effi ciency and low thermal resistance package backplane. However, in applica- tions in which the LTC3604 is running at a high ambient temperature, high input voltage, high switching frequency, and maximum output current, the heat dissipated may exceed the maximum junction temperature of the part. If the junction temperature reaches approximately 150° ...
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... PGOOD pin, however, with the limited current, no damage will result. Board Layout Considerations When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the LTC3604 the capacitors C to the pins as possible? These capacitors provide the 12V IN current to the internal power MOSFETs and drivers ...
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... LTC3604 APPLICATIONS INFORMATION V IN PGND GROUND VIAS TO GROUND PLANE C OUT VIA OUT V OUT VIAS PLANE INTVCC C BOOST VIAS TO PGND Figure 6. QFN Layout Example PGND OUT IN PIN ...
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... APPLICATIONS INFORMATION Design Example As a design example, consider using the LTC3604 in an application with the following specifi cations 12V 1.8V OUT OUT(MAX) 10mA 1MHz Because effi ciency is important at both high and low load currents, Burst Mode operation is selected. First, the correct R ...
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... Input to 1.8V Output at 4MHz Synchronized Frequency with 6V UVLO and 4.3ms Soft-Start V BOOST IN 0.1μF 154k L1 0.47μH RUN SW 40k V ON LTC3604 INTV FB CC 100k PGOOD ITH TRACK/SS RT 10nF MODE/SYNC 80k EXTERNAL SGND PGND CLOCK 3601 TA02a Effi ciency vs Load Current ...
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... 90. SGND PGND 20k 3604 TA03a Effi ciency vs Load Current 100 0.01 0 LOAD CURRENT (A) 3604 TA03b LTC3604 www.DataSheet4U.com V OUT 3.3V C 2.5A C OUT F 47μF 10pF C : TDK C3225X5R1C226M TDK C3216X5R0J476M OUT L1: VISHAY IHLP2020BZER1R0M01 21 3604f ...
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... LTC3604 PACKAGE DESCRIPTION 3.50 0.05 1.45 0.05 (4 SIDES) 2.10 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS 3.00 0.10 (4 SIDES) PIN 1 TOP MARK (NOTE 6) NOTE: 1. DRAWING CONFORMS TO JEDEC PACKAGE OUTLINE MO-220 VARIATION (WEED-2) 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. 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 ...
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... MAX SEATING PLANE 0.17 – 0.27 (.007 – .011) 0.50 TYP (.0197) BSC LTC3604 www.DataSheet4U.com 8 0.35 REF 1.651 0.102 0.12 REF (.065 .004) DETAIL “B” CORNER TAIL IS PART OF DETAIL “B” THE LEADFRAME FEATURE. FOR REFERENCE ONLY ...
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... Output at 2MHz Operating Frequency C2 2.2μ INTV RUN ITH 22μF RT PGOOD MODE/SYNC TRACK/SS BOOST 0.1μF LTC3604 SGND PGND C : TDK C3225X5R1C226M TDK C3225X5R0J476M OUT L1: VISHAY IHLP2020BZERR68M01 RELATED PARTS PART NUMBER DESCRIPTION LTC3603 15V, 2. 3MHz, Synchronous Step-Down DC/DC Converter ...