sc1173csw Semtech Corporation, sc1173csw Datasheet
sc1173csw
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sc1173csw Summary of contents
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... APPLICATIONS ® Pentium ll or Deschutes microprocessor supplies Flexible motherboards 1.3V to 3.5V microprocessor supplies Programmable dual power supplies ORDERING INFORMATION (1) Part Number Package SC1172CSW SO-24 SC1173CSW SO-24 Note: (1) Add suffix ‘TR’ for tape and reel. BLOCK DIAGRAM VCC CS- CS+ CURRENT LIMIT 1.25 REF VCC 70mV VID4 D/A & ...
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October 25, 1999 ABSOLUTE MAXIMUM RATINGS Parameter V to GND CC 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 to ...
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October 25, 1999 PIN DESCRIPTION Pin Pin Name Pin Function 1 AGND Small Signal Analog and Digital Ground connection Connection 4 LDOS Sense Input for LDO 5 VCC Input Voltage 6 OVP High Signal ...
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October 25, 1999 OUTPUT VOLTAGE Unless specified 4.75V to 5.25V; GND = PGND = 0V PARAMETER CONDITIONS Output Voltage Application Circuit O © 1999 SEMTECH CORP. PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER WITH LOW ...
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October 25, 1999 APPLICATION CIRCUIT © 1999 SEMTECH CORP. PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER WITH LOW DROPOUT REGULATOR CONTROLLER 652 MITCHELL ROAD NEWBURY PARK CA 91320 SC1172/3 5 ...
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October 25, 1999 MATERIALS LIST Qty. Reference Part/Description 4 C1,C5,C13,C 0.1µF Ceramic 18 6 C2,C3,C14- 1500µF/6.3V C17 3 C11,C12, 330µF/6.3V C21 1 L1 4µH 3 Q1,Q2,Q3 See notes 2.32k , 1%, 1/ ...
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October 25, 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 Lo Rds ...
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October 25, 1999 LAYOUT GUIDELINES Careful attention to layout requirements are necessary for successful implementation of the SC1172/3 PWM controller. High currents switching at 200kHz are pre- sent in the application and their effect on ground plane voltage differentials must ...
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October 25, 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 cop- per ...
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October 25, 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 requirements until ...
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October 25, 1999 FET type ( ( DS(on) BUK556H 22 2.48 IRL2203 7.0 0.79 Si4410 13.5 1.53 BOTTOM FET - Bottom FET losses are almost entirely due to conduction. The body diode is forced into conduc- ...
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October 25, 1999 OUTLINE DRAWING ECN99-667 © 1999 SEMTECH CORP. PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER WITH LOW DROPOUT REGULATOR CONTROLLER 652 MITCHELL ROAD NEWBURY PARK CA 91320 SC1172/3 JEDEC MS-013AD B17104B 12 ...