SC1186_04 SEMTECH [Semtech Corporation], SC1186_04 Datasheet
SC1186_04
Related parts for SC1186_04
SC1186_04 Summary of contents
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POWER MANAGEMENT Description The SC1186 combines a synchronous voltage mode controller with two low-dropout linear regulators providing most of the circuitry necessary to implement three DC/DC converters for powering advanced microprocessors such as Pentium II & III. ® The SC1186 ...
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POWER MANAGEMENT Absolute Maximum Ratings Exceeding the specifications below may result in permanent damage to the device, or device malfunction. Operation outside of the parameters specified in the Electrical Characteristics section is not implied. Exposure to Absolute Maximum rated conditions ...
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POWER MANAGEMENT Electrical Characteristics (Cont.) Unless specified: VCC = 4.75V to 5.25V; GND = PGND = 0V; VOSENSE = ...
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POWER MANAGEMENT Pin Configuration TOP VIEW AGND 1 24 GATE1 2 23 LDOS1 3 22 LDOS2 4 21 VCC 5 20 REF 6 19 LDOEN PGNDH PGNDL ...
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POWER MANAGEMENT Block Diagram REF VID4 VID3 D/A VID2 VID1 VID0 VOSENSE AGND LDOEN LDOS1 2.5V FET CONTROLLER GATE1 2004 Semtech Corp. VCC CS- CS+ EN CURRENT LIMIT 70mV + - + - - + ERROR AMP R Q OSCILLATOR ...
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POWER MANAGEMENT Applications Information - Output Voltage Table Unless specified: 4.75V < VCC < 5.25V; GND = PGND = 0V; VOSENSE = ...
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POWER MANAGEMENT Layout Guidelines Careful attention to layout requirements are necessary for successful implementation of the SC1186 PWM control- ler. High currents switching at 140kHz are present in the application and their effect on ground plane voltage differ- entials must ...
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POWER MANAGEMENT Layout Guidelines (Cont.) 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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POWER MANAGEMENT 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 the ...
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POWER MANAGEMENT Component Selection (Cont first order approximation convenient to only consider conduction losses to determine FET suitability. For a 5V in; 2.8V out at 14.2A requirement, typical FET losses would be: Using 1.5X Room temp ...
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POWER MANAGEMENT Theory of Operation (Linear OCP) The Linear controllers in the SC1186 have built in Overcurrent Protection (OCP). An overcurrent is assumed to have occured when the external FET is turned fully on and the output currrent is R ...
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POWER MANAGEMENT Typical Characteristics Typical Efficiency (Switching section) 96% PIN Descriptions 92% 88% 84% Vo=2.8V 80% Vo=2.0V Vo=2.5V 76% 0.0 2.0 4.0 6.0 8.0 Io (Amps) Transient Response Vo=2.4V, Io=300mA to 15A 2004 Semtech Corp. 10.0 12.0 14.0 16.0 2.5V ...
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POWER MANAGEMENT Evaluation Board Schematic 2004 Semtech Corp. 13 SC1186 www.semtech.com ...
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POWER MANAGEMENT Evaluation Board Bill of Materials ...
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POWER MANAGEMENT Outline Drawing - SO- E/2 R ccc N/2 TIPS aaa C SEATING PLANE C J NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. DATUMS -A- 3. DIMENSIONS "E1" AND "D" ...