LTC3527 Linear Technology Corporation, LTC3527 Datasheet
LTC3527
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LTC3527 Summary of contents
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... The ⎯ S ⎯ H ⎯ D ⎯ N and PGOOD pins enable the converters to be sequenced or started together. The LTC3527/LTC3527-1 limit inrush current during start- up. Selectable 1.2MHz or 2.2MHz operation provides a choice between the highest effi ciency or smallest solu- tion footprint. The current mode PWM design is internally ® ...
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... LTC3527EUD-1#PBF LTC3527EUD-1#TRPBF LEAD BASED FINISH TAPE AND REEL LTC3527EUD LTC3527EUD#TR LTC3527EUD-1 LTC3527EUD-1#TR Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. For more information on lead free part marking, go to: For more information on tape and reel specifi cations, go to: ELECTRICAL CHARACTERISTICS temperature range, – ...
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... Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC3527E/LTC3527E-1 are guaranteed to meet performance specifi cations from 0°C to 85°C. Specifi cations over the –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls ...
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... LTC3527/LTC3527-1 TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency vs Load Current and V for V = 1.8V at 1.2MHz OUT1 100 1.2V 1.5V 90 BURST FIXED 60 www.DataSheet4U.com 0.01 0 LOAD CURRENT (mA) Effi ciency vs Load Current and V for V = 3.3V at 2.2MHz OUT1 100 2. BURST 1. FIXED 0.01 0 ...
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... G12 for OUT1 OUT2 CONVERTER 1 LEAVE BURST CONVERTER 2 ENTER BURST CONVERTER 2 CONVERTER 1 1.5 2 2.5 3 3.5 4 4.5 V (V) IN 35271 G15 LTC3527/LTC3527 25°C, unless otherwise noted) A Maximum Output Current vs V for Converter 2 IN 500 V = 3.3V OUT 450 400 V OUT 350 2. 300 OUT 1.8V 250 ...
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... LTC3527/LTC3527-1 TYPICAL PERFORMANCE CHARACTERISTICS Current Limit vs Temperature 1.30 CONVERTER1 1.20 1. 1. 3.3V OUT 0.90 www.DataSheet4U.com 0.80 0.70 CONVERTER2 0.60 0.50 –45 –30 – TEMPERATURE (°C) Burst Mode Quiescent Current vs V OUT 1. 1.5 2 (V) OUT Fixed Frequency Switching Waveform and V SW1 PIN 2V/DIV V OUT1 ...
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... During Start-Up IN 35271 G25 100µs/DIV = 3.3V = 10µF Load Step Response 35271 G27 100µs/DIV 20mA TO 170mA STEP = 10µF OUT1 LTC3527/LTC3527 25°C, unless otherwise noted Load Step Response OUT1 Fixed Frequency at 1.2MHz V OUT1 100mV/DIV AC COUPLED LOAD CURRENT ...
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... Output. This open-drain output is low when below its regulation voltage. GND (Pin 14): Signal Ground. This pin is used Keep these PCB trace IN1 ground reference for the internal circuitry of the LTC3527/ LTC3527- Operation section for more information. to minimize EMI. ...
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... SHUTDOWN SENSE SD2 AND V BIAS MODE PWM CONTROL COMP + + – LIM REF SLOPE COMPENSATION BURST2 SLP2 PGOOD2 13 – FB2 + 1.20V - 9% CONVERTER 2 LTC3527/LTC3527-1 BULK CONTROL SIGNALS OUT V OUT1 V OUT1 5 1.6V TO 5.25V 0.40Ω – I ZERO COMP MODE WAKE1 R1 FB1 – OUT1 + 4.7µ ...
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... Operation can be best understood by referring to the Block Diagram. A PGOOD signal is provided independently for each con- verter which can be used with the ⎯ S ⎯ H ⎯ D ⎯ N pins to provide sequencing of the outputs. The LTC3527-1 provides an instant off feature which discharges OUT1 OUT2 pins go low ...
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... If one channel is shut down, then Burst Mode operation is enabled on the other channel. With the MODE pin low, the LTC3527/LTC3527-1 will automatically enter Burst Mode operation at light load and return to fi xed frequency PWM mode when the load increases ...
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... Burst Mode operation is inhibited during start-up and soft- start and until both V greater than V ) and FB1 (FB2). When the MODE pin is high, LTC3527/LTC3527-1 features continuous PWM fi xed frequency operation at 1.2MHz (FSEL = Low) or 2.2MHz (FSEL = High). At very light loads, the LTC3527/LTC3527-1 will exhibit pulse-skip operation ...
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... Molded chokes and some chip inductors usually do not have enough core area to support the peak inductor currents of 900mA (500mA) seen on the LTC3527/LTC3527-1. To minimize radiated – noise, use shielded inductors. See Table 1 for suggested ...
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... TDK www.global.tdk.co.jp Taiyo Yuden www.t-yuden.com The internal loop compensation of the LTC3527/ LTC3527-1 is designed to be stable with output capacitor values of 4.7µF or greater. Although ceramic capacitors are recommended, low ESR tantalum capacitors may be used as well. A small ceramic capacitor in parallel with a larger tantalum capacitor may be used in demanding applications which have large load transients ...
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... FB1 PGOOD1 1.21M ON SHDN1 OFF MODE ON OFF L: SUMIDA CDRH3D164R7 TAIYO YUDEN X5R JMK212BJ475MD IN OUT 1.5V 1.5V 1.2V 1V FIXED 10 100 1000 35271 TA02b LTC3527/LTC3527-1 = 1.8V OUT2 4.7µ IN2 SW2 V OUT V 1.8V OUT2 150mA 612k FB2 1.21M PGOOD2 C OUT2 SHDN2 4.7µF GND FSEL 35271 TA02 Boost 2 Effi ...
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... LTC3527/LTC3527-1 TYPICAL APPLICATIONS V OUT 1.8V 200mA www.DataSheet4U.com Boost 1 Effi ciency 100 1.2V 90 BURST 0.01 0.1 1 LOAD CURRENT (mA) 16 1.2MHz, 1-Cell 1.8V, V OUT1 0.85V TO 1.60V + SINGLE C IN ALKALINE 4.7µF 4.7µ CELL IN1 SW1 V OUT1 C OUT1 612M 4.7µF FB1 PGOOD1 1.21M ...
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... FB1 PGOOD1 1M ON SHDN1 OFF MODE GND ON OFF , C : TAIYO YUDEN X5R JMK212BJ475MD IN OUT 1.5V 1.5V 1.2V 1V FIXED 1 10 100 1000 35271 TA04b LTC3527/LTC3527-1 = 1.8V OUT2 2.2µH V IN2 SW2 V OUT V 1.8V OUT2 150mA 612k FB2 1.21M PGOOD2 C OUT2 SHDN2 4.7µF FSEL 35271 TA04 Boost 2 Effi ciency 100 1 ...
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... LTC3527/LTC3527-1 TYPICAL APPLICATIONS V OUT 5V 300mA www.DataSheet4U.com Boost 1 Effi ciency 100 2.4V 90 BURST 80 1. 0.01 0.1 LOAD CURRENT (mA) 18 1.2MHz, 2-Cell 5V, V OUT1 1. ALKALINE + 4.7µF 10µH CELLS V IN1 SW1 V OUT1 C OUT1 3.24M 4.7µF FB1 PGOOD1 1.02M ON SHDN1 OFF MODE ON OFF ...
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... 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. LTC3527/LTC3527-1 BOTTOM VIEW—EXPOSED PAD PIN 1 NOTCH R = 0.20 TYP R = 0.115 OR 0.25 × ...
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... LTC3527/LTC3527-1 TYPICAL APPLICATION Sequenced Start-Up V 1.2MHz, 1-Cell to V OUT1 0.85V TO 1.60V + SINGLE C IN ALKALINE 4.7µF 4.7µH V CELL IN1 SW1 V OUT V 1.8V OUT1 C 200mA OUT1 612k 4.7µF FB1 PGOOD1 1.21M ON SHDN1 www.DataSheet4U.com OFF MODE L: SUMIDA CDRH3D164R7 TAIYO YUDEN X5R JMK212BJ475MD IN OUT RELATED PARTS ...