LTC3601 Linear Technology, LTC3601 Datasheet
LTC3601
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LTC3601 Summary of contents
Page 1
... The LTC3601 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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... LTC3601EUD#PBF LTC3601EUD#TRPBF LTC3601IUD#PBF LTC3601IUD#TRPBF LTC3601EMSE#PBF LTC3601EMSE#TRPBF LTC3601IMSE#PBF LTC3601IMSE#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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... MODE = 0V MODE = INTV CC Note 2: The LTC3601E is guaranteed to meet performance specifi cations 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. The LTC3601I is guaranteed over the – ...
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... Note 4: Maximum allowed current draw when used as a regulated output A 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 LTC3601 operation. = 38°C/W for the MSOP JA Effi ciency vs Load Current ...
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... Oscillator Internal Set Frequency vs Temperature 2. NTVCC 2.50 2.25 2.00 1.75 1.50 1.25 125 –50 – TEMPERATURE (°C) 3601 G10 50 100 125 75 3601 G11 LTC3601 Quiescent Current vs Supply Voltage 380 340 300 260 220 100 125 SUPPLY VOLTAGE (V) 3601 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 – ...
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... LTC3601 TYPICAL PERFORMANCE CHARACTERISTICS T = 25° 12V 1MHz 2.2μH unless otherwise noted Output Voltage vs Time Burst Mode Operation SW 5V/DIV V OUT 20mV/DIV AC COUPLED I L 1A/DIV V = 12V 2μs/DIV 1.8V OUT I = 100mA 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 LTC3601 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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... LTC3601 FUNCTIONAL BLOCK DIAGRAM 180k CONTROLLER OSC R RT MODE/SYNC OSC PLL-SYNC www.DataSheet4U.com Q2 I THB 0.6V REF INTERNAL SOFT-START 8 QFN Package 0.72V 6V V VON = R I ION S Q SWITCH LOGIC ON AND 15k + + ANTI- SHOOT I I REV THROUGH CMP – ...
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... At low load currents the inductor current can drop to zero or become negative. If the LTC3601 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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... LTC3601 APPLICATIONS INFORMATION A general LTC3601 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 LTC3601 design includes an overvoltage protection 5.2 × 5.5 2 circuit, care must always be taken to ensure input volt- age 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 LTC3601 will adjust the output voltage such that V equals the reference voltage of 0.6V according to 0.6V 1+ ...
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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 LTC3601 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 LTC3601 allows the user to control the output voltage ramp rate by means of the TRACK pin. From 0V to 0.6V the TRACK pin will override the internal reference input to the error amplifi er forcing regulation of the feedback voltage to that seen at the TRACK pin ...
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... Mode operation to prevent inductor saturation and improve TRACK pin accuracy. Output Power Good The PGOOD output of the LTC3601 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 www ...
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... In many applications, the LTC3601 does not dissipate much heat due to its high effi ciency and low thermal resistance package backplane. However, in applica- tions in which the LTC3601 is running at a high ambient temperature, high input voltage, high switching frequency, and maximum output current, the heat dissipated may ...
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... Board Layout Considerations When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the LTC3601 the capacitors C connect the pins as possible? These capacitors provide the AC current to the internal power MOSFETs and drivers. The (– ...
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... LTC3601 APPLICATIONS INFORMATION V IN PGND VIAS TO GROUND PLANE C OUT VIA OUT www.DataSheet4U.com VIAS GROUND 1 PLANE BOOST VIAS TO PGND Figure 5. QFN Layout Example V PGND OUT C OUT PIN BOOST SW C INTVCC ...
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... APPLICATIONS INFORMATION Design Example As a design example, consider using the LTC3601 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 IN 154k L1 0.68μH RUN SW 40k V ON LTC3601 INTV FB CC 100k PGOOD ITH TRACK RT MODE/SYNC 80k EXTERNAL SGND PGND CLOCK 3601 TA02a Effi ciency vs Load Current 90 80 ...
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... BOOST L1 0.1μF LTC3601 2.2μ SGND PGND 3601 TA03a Effi ciency vs Load Current 100 0.01 0.1 1 LOAD CURRENT (A) LTC3601 V OUT 3. OUT FF 47μF 90.9k 10pF TDK C3225X5R1C476M IN 20k C : TDK C3216X5R0J476M OUT L1: VISHAY IHLP2020BZER2R2M01 10 3601 TA03b 3601f 21 ...
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... LTC3601 PACKAGE DESCRIPTION 3.50 0.05 1.45 0.05 (4 SIDES) 2.10 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS www.DataSheet4U.com 22 UD Package 16-Lead Plastic QFN (3mm × 3mm) (Reference LTC DWG # 05-08-1691) 0.70 0.05 PACKAGE OUTLINE 0.25 0.05 0.50 BSC 0.75 0.05 3.00 0.10 (4 SIDES) PIN 1 TOP MARK (NOTE 6) 1.45 0.10 (4-SIDES) 0.200 REF 0.00 – 0.05 NOTE: 1. DRAWING CONFORMS TO JEDEC PACKAGE OUTLINE MO-220 VARIATION (WEED-2) 2 ...
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... DETAIL “A” 1.10 (.043) MAX SEATING PLANE 0.17 – 0.27 (.007 – .011) 0.50 TYP (.0197) BSC LTC3601 8 0.35 REF 1.651 0.102 0.12 REF (.065 .004) DETAIL “B” CORNER TAIL IS PART OF THE LEADFRAME FEATURE. DETAIL “B” FOR REFERENCE ONLY 9 ...
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... TYPICAL APPLICATION 1.2V Output at 2MHz Operating Frequency INTV IN CC 12V C1 RUN ITH 22μF RT PGOOD MODE/SYNC TRACK BOOST LTC3601 SGND PGND C : TDK C3225X5R1C226M TDK C3225X5R0J476M OUT L1: VISHAY IHLP2020BZER1R0M01 RELATED PARTS PART NUMBER DESCRIPTION LTC3412A 5.5V 4MHz, Synchronous Step-Down DC/DC Converter ...