SC1109ACSTR SEMTECH [Semtech Corporation], SC1109ACSTR Datasheet
SC1109ACSTR
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SC1109ACSTR Summary of contents
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... MOSFETs used) until regulation Integrated drivers Power good signal (SC1109A, SC1109B) Soft start Lossless current sense Programmable over current limit (SC1109C) 200kHz (SC1109A, SC1109C), and 500kHz (SC1109B) fixed frequency. Applications Pentium Triple power supplies C2 C3 SC1109ACSTR or SC1109BCSTR C4 2x1500uF 0.1uF 0.1uF + 11 3 VCC STBY C5 0.1uF 4 ...
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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 ...
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POWER MANAGEMENT Electrical Characteristics (Cont.) Unless specified: VOSENSE = V ; Vcc=4.75V to 5.25V; STBY=4.75V to 5.25V; BST = 11.4V to 12.6V ...
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POWER MANAGEMENT Pin Configuration Top View LDOS1 1 16 GATE1 2 15 STBY 3 14 BCAP BCAP GND 6 11 PHASE (SC1109A/B) Ordering Information ...
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POWER MANAGEMENT Block Diagram VCC PWRGD VOSENSE SC1109A/B SS/EN STBY BCAP+ BCAP- VCC VOSENSE SC1109C SS/EN STBY BCAP+ BCAP- Marking Information SC1109ACS SC1109A yyww xxxxx yyww = Datecode (Example: 9912) xxxxx = Semtech Lot # (Example: 90101) 2004 Semtech Corp. ...
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POWER MANAGEMENT Application Information THEORY OF OPERATION The SC1109 has integrated a synchronous buck control- ler and two Low drop out regulator controllers into a 16 Pin SOIC package. The switching regulator provides a 1.2V (VTT) bus termination voltage for ...
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POWER MANAGEMENT Application Information (Cont.) An internal comparator with a 200mV reference moni- tors the Drop across the upper FET, Once the Vdson of the MOSFET exceeds the 200mV limit, the low side gate is turned on and the upper ...
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POWER MANAGEMENT Application Information (Cont.) The internal charge pump charges an external Bucket capacitor to VSTBY and then connects it in series with VSTBY to the LDOs supply at a frequency of about 200kHz. This ensures sufficient gate drive voltage ...
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POWER MANAGEMENT Application Information (Cont.) 4) The Output Capacitor(s) (Cout) should be located as close to the load as possible, fast transient load cur- rents sre supplied by Cout only, and connections between Cout and the load must be short, ...
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POWER MANAGEMENT Application Information (Cont.) COMPONENT SELECTION SWITCHING SECTION OUTPUT CAPACITORS - Selection begins with the most critical component. Because of fast transient load cur- rent requirements in modern microprocessor core sup- plies, the output capacitors must supply all transient ...
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POWER MANAGEMENT Application Information (Cont.) or more generally Body diode recovery losses are more difficult to esti- mate, but to a first approximation reasonable to assume that ...
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POWER MANAGEMENT SC1109 Gain & Phase Margin -10 -20 10 100 Typical VTT Gain/Phase plot at Vin = 5V, Iout = 3A 2004 Semtech Corp. SC1109A Gain & Phase Margin Gain Phase Margin 1,000 ...
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POWER MANAGEMENT Typical Characteristics SC1109 Quiescent Current vs Ta 7.90 Vcc = 5.25 7.85 Vcc = 4.75 7.80 7.75 7.70 7.65 7.60 7.55 7.50 7.45 7. (°C.) Typical Icc (Switching section) SC1109 Soft start ...
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POWER MANAGEMENT Typical Characteristics SC1109 Tracking Difference (Io LDO1 280.0 260.0 240.0 220.0 200.0 LDO2 Vcc = 4.75 LDO2 Vcc = 5.25 180.0 LDO1 Vcc = 4.75 LDO1 Vcc = 5.25 160 ...
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POWER MANAGEMENT Typical Characteristics SC1109 (VTT) Eff. vs Iout (Vin = 5.0V) 90.0% 80.0% 70.0% 60.0% 50.0% 40.0% 30.0% 20.0% IRL3103R(V1.8,V2.5 No load) 10.0% 0.0% 0.00 2.00 4.00 Iout_Vtt (Amps) Typical VTT Efficiency at Vin=5V SC1109 (VTT) Load Reg. vs ...
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POWER MANAGEMENT Evaluation Board Schematic J1 12V IN J2 GND 5V STBY J3 GND 0.1uF + R1 1500uF 10k C5 + 1500uF GND J8 GND J10 POWER GOOD J11 C16 0.1uF ...
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POWER MANAGEMENT Evaluation Board Bill of Materials ...
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POWER MANAGEMENT Evaluation Board Gerber Plots Board Layout Assembly Top Board Layout Top 2004 Semtech Corp. Board Layout Bottom 18 SC1109 www.semtech.com ...
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POWER MANAGEMENT Outline Drawing - SO-16 Land Pattern - SO-16 Contact Information Phone: (805)498-2111 FAX (805)498-3804 2004 Semtech Corp. Semtech Corporation Power Management Products Division 200 Flynn Road, Camarillo, CA 93012 19 SC1109 www.semtech.com ...