LTC1553CSW Linear Technology, LTC1553CSW Datasheet
LTC1553CSW
Specifications of LTC1553CSW
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LTC1553CSW Summary of contents
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... The LTC1553 free-runs at 300kHz and can be synchronized to a faster external clock if desired. It includes all the inputs and outputs required to implement a power supply conform- ing to the Intel Pentium Converter Specification . , LTC and LT are registered trademarks of Linear Technology Corporation. Pentium is a registered trademark of Intel Corporation 12V + 0 ...
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... OUTEN = 0, VID0 to VID4 Floating CC (Figure 4) (Note 4) (Note 4) (Note 7) (Note 7) COMP = Open (Note INFORMATION TOP VIEW ORDER PART NUMBER OUTEN 3 VID0 18 LTC1553CG 4 17 VID1 LTC1553CSW 5 16 VID2 6 VID3 VID4 8 13 PWRGD 9 FAULT PACKAGE 20-LEAD PLASTIC SO = 125 C, = 100 125 C, = 100 C/ W (SW unless otherwise noted ...
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ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER I I Sink Current IMAX MAX I Soft Start Source Current SS I Maximum Soft Start Sink Current SSIL Under Current Limit I Soft Start Sink Current Under Hard SSHIL Current Limit t Hard Current Limit ...
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LTC1553 W U TYPICAL PERFORMANCE CHARACTERISTICS Typical 2.8V V Distribution OUT 140 TOTAL SAMPLE SIZE = 1500 120 100 100 2.775 2.785 2.795 2.805 2.815 2.825 OUTPUT VOLTAGE (V) 1553 G01 Line ...
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W U TYPICAL PERFORMANCE CHARACTERISTICS Oscillator Frequency vs Temperature 350 340 330 320 310 300 290 280 270 260 250 50 125 –50 – 100 TEMPERATURE ( C) 1553 G10 Maximum G1 Duty Cycle vs Temperature 92 ...
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LTC1553 PIN FUNCTIONS G2 (Pin 1): Gate Drive for the Lower N-Channel MOSFET, Q2. This output will swing from low when G1 is high or when the output is disabled. To prevent undershoot during ...
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PIN FUNCTIONS VID0, VID1, VID2, VID3, VID4 (Pins 18, 17, 16, 15, 14): Digital Voltage Select. TTL inputs used to set the regulated output voltage required by the processor (Table 3). There is an internal 20k pull-up ...
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LTC1553 TEST CIRCUITS 100pF 100pF VID0 TO VID4 100pF R C 8.2k C1 150pF C 0. 0.1 F 10k SENSE ...
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CTIO TABLES Table 1. OT Logic OUTEN (V) < 2 > 2 Table 2. PWRGD and FAULT Logic INPUT OUTEN SENSE < 95 > 95% 1 < 105% ...
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LTC1553 U U APPLICATIONS INFORMATION OVERVIEW The LTC1553 is a voltage feedback, synchronous switch- ing regulator controller (see Block Diagram) designed for use in high power, low voltage step-down (buck) convert- ers designed to satisfy the requirements of ...
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U U APPLICATIONS INFORMATION Soft Start and Current Limit The LTC1553 includes a soft start circuit which is used for initial start-up and during current limit operation. The SS pin requires an external capacitor to GND with the value determined ...
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LTC1553 U U APPLICATIONS INFORMATION Table 4. Recommended Minimum R IMAX MAXIMUM OPERATING LOAD CURRENT (A) SUD50N03-10 12 2.4 14 2.7 16 3.0 18 3.6 20 3.9 OUTEN and Thermistor Input The LTC1553 includes a low power shutdown mode, controlled ...
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U U APPLICATIONS INFORMATION MOSFET Gate Drive Power for the internal MOSFET drivers is supplied This supply must be above the input supply voltage least one power MOSFET V GS(ON) tion. This higher voltage ...
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LTC1553 U U APPLICATIONS INFORMATION The LTC1553 designs that use doubler charge pump to generate PV enough drive voltage to fully enhance standard power MOSFETs. Under this condition, the effective MOSFET R may be quite high, raising ...
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U U APPLICATIONS INFORMATION Table 5. Recommended MOSFETs for LTC1553 Applications R DS(ON) PARTS Siliconix SUD50N03-10 TO-252 Siliconix Si4410DY SO-8 Motorola MTD20N03HDL D PAK SGS-Thomson STD20N03L D PAK Motorola MTB75N03HDL DD PAK IRF IRL3103S DD ...
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LTC1553 U U APPLICATIONS INFORMATION Solving this equation with our typical 5V to 2.8V applica- tion with inductor, we get P-P 300 kHz 2 H Peak inductor current at 11.2A load: ...
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U U APPLICATIONS INFORMATION application might exhibit 5A input ripple current. SANYO OS-CON part number 10SA220M (220 F/10V) capacitors feature 2.3A allowable ripple current three in parallel at the input (to withstand the input ripple current) will ...
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LTC1553 U U APPLICATIONS INFORMATION complication of input and/or output filters, unknown capacitor ESR, and gross operating point changes with input voltage, load current variations, all suggest a more practical empirical method. This can be done by injecting a transient ...
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U U APPLICATIONS INFORMATION 15% V OUT 5% RATED V OUT –5% t PWRBAD t PWRGD PWRGD FAULT Figure 11. PWRGD and FAULT LAYOUT CONSIDERATIONS When laying out the printed circuit board, the following checklist should be used to ensure ...
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LTC1553 U U APPLICATIONS INFORMATION + OUT + C Q2 OUT BOLD LINES INDICATE HIGH CURRENT PATHS 0.1 F ...
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U U APPLICATIONS INFORMATION 5.6k 5.6k PENTIUM II SYSTEM 5 5V 1.8k C1 DALE 150pF NTHS-1206N02 MOUNT THERMISTER IN CLOSE THERMAL PROXIMITY TO Q1 Figure 13. Single Supply LTC1553 5V to 1.8V-3.5V Application with Thermal Monitor 0.1 ...
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LTC1553 PACKAGE DESCRIPTION 0.205 – 0.212** (5.20 – 5.38) 0.005 – 0.009 0.022 – 0.037 (0.13 – 0.22) (0.55 – 0.95) * DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSIONS DO ...
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... DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... C OUT 15V 330 F 6 Q2* * MOTOROLA MTD20N03HDL ** SANYO 16MV1000GX † COILTRONICS CTX02-13199 †† AVX TPSE337M006R0100 20V IN 48V, for Standard Threshold FETs IN 40V, for Logic Threshold FETs IN 36V IN 1553f LT/TP 0198 4K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1997 v OUT 1553 F14 ...