SC1185CSW Semtech Corporation, SC1185CSW Datasheet
SC1185CSW
Related parts for SC1185CSW
SC1185CSW Summary of contents
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... Pentium ll microprocessor supplies Flexible motherboards 1.3V to 3.5V microprocessor supplies Programmable triple power supplies ORDERING INFORMATION (1) Part Number SC1185CSW (2) SC1185ACSW Note: (1) Add suffix ‘TR’ for tape and reel. (2) SC1185A provides improved output tolerance. See Output Voltage Table. BLOCK DIAGRAM VCC CS- CS+ REF ...
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PRELIMINARY - January 6, 1999 ABSOLUTE MAXIMUM RATINGS Parameter VCC to GND PGND to GND BST to GND Operating Temperature Range Junction Temperature Range Storage Temperature Range Lead Temperature (Soldering) 10 seconds Thermal Impedance Junction to Ambient Thermal Impedance Junction ...
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PRELIMINARY - January 6, 1999 PIN DESCRIPTION Pin Pin Name Pin Function 1 AGND Small Signal Analog and Digital Ground 2 GATE1 Gate Drive Output LDO1 3 LDOS1 Sense Input for LDO1 4 LDOS2 Sense Input for LDO2 5 VCC ...
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PRELIMINARY - January 6, 1999 OUTPUT VOLTAGE Unless specified: 4.75V < VCC < 5.25V; GND = PGND = 0V; VOSENSE = V PARAMETER VID 43210 Output Voltage 01111 01110 01101 01100 01011 01010 01001 01000 00111 00110 00101 00100 00011 ...
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PRELIMINARY - January 6, 1999 APPLICATION CIRCUIT © 1999 SEMTECH CORP. PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL LOW DROPOUT REGULATOR CONTROLLER 652 MITCHELL ROAD NEWBURY PARK CA 91320 SC1185 SC1185A 5 ...
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... 2.32k , 1%, 1/ 1%, 1/ 5%, 1/ SC1185CSW © 1999 SEMTECH CORP. PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL LOW DROPOUT REGULATOR CONTROLLER Vendor Notes Various SANYO MV-GX or equiv. Low ESR Various 8 Turns 16AWG on MICROMETALS T50-52D core See notes FET selection requires trade-off between efficiency and cost ...
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PRELIMINARY - January 6, 1999 95% 90% 85% 80% 3.5V Std 3.5V Sync 3.5V Sync Lo Rds 75% 70 (Amps) Typical Efficiency at Vo=3.5V 95% 90% 85% 80% 2.5V Std 2.5V Sync 2.5V Sync ...
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PRELIMINARY - January 6, 1999 LAYOUT GUIDELINES Careful attention to layout requirements are necessary for successful implementation of the SC1185 PWM controller. High currents switching at 140kHz are pre- sent in the application and their effect on ground plane voltage ...
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PRELIMINARY - January 6, 1999 4) The Output Capacitor(s) (Cout) should be located as close to the load as possible, fast transient load currents are supplied by Cout only, and connections between Cout and the load must be short, wide ...
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PRELIMINARY - January 6, 1999 COMPONENT SELECTION SWITCHING SECTION OUTPUT CAPACITORS - Selection begins with the most critical component. Because of fast transient load current requirements in modern microprocessor core supplies, the output capacitors must supply all transient load current ...
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PRELIMINARY - January 6, 1999 Using 1.5X Room temp R to allow for temperature DS(ON) rise. FET type ( ( DS(on) IRL34025 15 1.69 IRL2203 10.5 1.19 Si4410 20 2.26 BOTTOM FET - Bottom FET losses ...
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PRELIMINARY - January 6, 1999 OUTLINE DRAWING © 1999 SEMTECH CORP. PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL LOW DROPOUT REGULATOR CONTROLLER 652 MITCHELL ROAD NEWBURY PARK CA 91320 SC1185 SC1185A JEDEC MS-013AD B17104B 12 ...