LTC3520EUF#PBF Linear Technology, LTC3520EUF#PBF Datasheet
LTC3520EUF#PBF
Specifications of LTC3520EUF#PBF
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LTC3520EUF#PBF Summary of contents
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... Handheld PCs, PDAs n GPS Receivers L, LT, LTC, LTM, Linear Technology, the Linear logo 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 5481178, 6166527, 6304066, 6404251, 6580258. TYPICAL APPLICATION 3 ...
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... Maximum Junction Temperature (Note 5) ............ 125°C Storage Temperature Range .................. –65°C to 150°C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC3520EUF#PBF LTC3520EUF#TRPBF LTC3520IUF#PBF LTC3520IUF#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. ...
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ELECTRICAL CHARACTERISTICS junction temperature range, otherwise specifi cations are at T unless otherwise noted. PARAMETER Feedback Voltage (FB2 Pin) Feedback Input Current (FB2 Pin) PMOS Current Limit Maximum Duty Cycle Minimum Duty Cycle Soft-Start Charging Current SD2 Input High Voltage ...
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LTC3520 ELECTRICAL CHARACTERISTICS junction temperature range, otherwise specifi cations are at T otherwise noted. PARAMETER Propagation Delay SD3 Input High Voltage SD3 Input Low Voltage SD3 Input Current Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause ...
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TYPICAL PERFORMANCE CHARACTERISTICS Buck Effi ciency Lithium-Ion to 1.8V 100 Burst Mode 90 OPERATION SUMIDA CDRH3D16NP-4R7N 249k BURST LOAD CURRENT (mA) LDO Load Transient Response ...
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LTC3520 TYPICAL PERFORMANCE CHARACTERISTICS Buck Burst Mode Threshold V = 1.8V OUT 4.7μ BURST = 274k 249k BURST 301k BURST 5 0 2.2 2.7 3.2 ...
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TYPICAL PERFORMANCE CHARACTERISTICS Buck-Boost Output Voltage vs Load Current 0.5 0.4 0 –40° 25°C A 0.1 0 –0 125°C A –0.2 –0.3 –0.4 –0.5 0 200 400 600 800 1000 1200 LOAD ...
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LTC3520 PIN FUNCTIONS SV (Pin 1): Small Signal Power Supply Connection. IN This pin is used to power the internal circuitry of the LTC3520. This pin should be bypassed using a 0.1μF or larger ceramic capacitor placed as close as ...
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PIN FUNCTIONS SS2 (Pin 13): Buck Converter Soft-Start Pin. This pin must be connected to a soft-start capacitor. The value of the capacitor determines the duration of the soft-start period. For information on choosing the value of this capacitor, see ...
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LTC3520 BLOCK DIAGRAM IN1 IN3 PGND1 Gm – – 3A PWM1 5 SD1 6 SD3 – 0.786V A OUT 2 INTERNAL ...
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OPERATION The LTC3520 combines a synchronous buck DC/DC converter and a four-switch buck-boost DC/DC converter in a single 4mm × 4mm QFN package. The buck-boost converter utilizes a proprietary switching algorithm which allows its output voltage to be regulated above, ...
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LTC3520 OPERATION This leads to a reduced output current capability at large step-down ratios. In contrast, the LTC3520 performs cur- rent limiting prior to the addition of the slope compensation ramp and therefore achieves a peak inductor current limit that ...
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OPERATION Error Amplifi er The error amplifi er operates in voltage mode. Appropriate loop compensation components must be utilized around the amplifi er (between the FB1 and V to ensure stable operation. For improved bandwidth, an additional RC feedforward network ...
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LTC3520 OPERATION COMMON FUNCTIONS Oscillator The buck-boost and buck converters operate from a com- mon internal oscillator. The switching frequency for both converters is set by the value of an external resistor, R located between the R pin and ground ...
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APPLICATIONS INFORMATION The basic LTC3520 application circuit is shown as the Typical Application on the front page of this datasheet. The external component selection is determined by the desired output voltages, output currents, and ripple volt- age requirements of each ...
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LTC3520 APPLICATIONS INFORMATION output capacitors. Larger value output capacitors can be accommodated provided they have suffi cient ESR to stabilize the loop or by adding a feedforward capacitor in parallel with the upper feedback resistor. Table 2. Buck Output Capacitor ...
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APPLICATIONS INFORMATION In addition to affecting output current ripple, the size of the inductor can also affect the stability of the feedback loop. In boost mode, the converter transfer function has a right half plane zero at a frequency that ...
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LTC3520 APPLICATIONS INFORMATION Capacitor Vendor Information Both the input and output capacitors used with the LTC3520 must be low ESR and designed to handle the large AC cur- rents generated by switching converters. The vendors in Table 4 provide capacitors ...
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APPLICATIONS INFORMATION Most applications require a faster transient response than can be attained using Type I compensation in order to reduce the size of the output capacitor. To achieve a higher loop bandwidth, Type III compensation is required, providing two ...
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LTC3520 APPLICATIONS INFORMATION R T SGND UNINTERRUPTED GROUND PLANE MUST EXIST UNDER ALL COMPONENTS SHOWN IN BOLD AND UNDER TRACES CONNECTING TO THOSE COMPONENTS. VIA TO GROUND PLANE FB1 SS1 SV 1 ...
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TYPICAL APPLICATIONS V IN 2.2V TO 4.2V C1 Li-Ion 22μF V OUT 1.8V 600mA 255k 27pF C2 22μF 200k BURST PWM OFF ON 470pF C1, C2, C3: TAIYO YUDEN CERAMIC JMK212BJ226MG-T L1: TDK RLF7030T-4R7M3R4 4.7μH L2: TDK RLF7030T-3R3M4R 3.3μH Sequenced ...
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LTC3520 TYPICAL APPLICATIONS V IN 2.2V TO 4.2V C1 Li-Ion 22μF V 3.3μH OUT 1.2V 600mA 27pF 100k C2 22μF 191k BURST PWM OFF ON C1, C2, C3: TAIYO YUDEN CERAMIC JMK212BJ226MG-T L1: TDK RLF7030T-4R7M3R4 4.7μH L2: TDK RLF7030T-3R3M4R 3.3μH ...
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... ON THE TOP AND BOTTOM OF PACKAGE 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. UF Package 24-Lead Plastic QFN (4mm × ...
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... QFN Package 180μA, I < 1μA, QFN Package 2.2V to 5.25V, Buck OUT(RANGE) OUT(RANGE) = 40μA, I < 1μA, DFN and 35μA, I < 1μA, DFN and 0.6V 40μA, I < 1μA, DFN and OUT(MIN 0609 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2007 , IN 3520fa ...