sc286ultrt Semtech Corporation, sc286ultrt Datasheet
sc286ultrt
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sc286ultrt Summary of contents
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... SSA PGOODA PGNDA PVINB R 1Ω AVINB AVINB SSB C 0.1µF AVINB PGNDB AGNDB PGOODB CTL0A CTL0B CTL1A CTL1B CTL2A CTL2B CTL3A CTL3B © 2011 Semtech Corporation Step-Down Regulator L 1.0µ OUTA C OUTA 47µF L 1.0µ OUTB C OUTB 47µF C SSA 1nF C SSB ...
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... Marking Information SC286 yyww XXXXX XXXXX yyww = Date code XXXXX = Semtech Lot number XXXXX = Semtech Lot number Ordering Information SC286ULTRT 23 22 Notes: CTL2B 21 (1) Available in tape and reel only. A reel contains 3,000 devices. CTL1B 20 (2) Device is lead-free, Halogen free, and RoHS/WEEE compliant. ...
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Absolute Maximum Ratings PVINA/B and AVINA/B Supply Voltages ( -0.3 to +6.0 LXA, LXB ( -0.3 to PVIN +0.3V, 6V Max (1) ...
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Electrical Characteristics (continued) Parameter Symbol Load Regulation ΔV Oscillator Frequency Soft-Start Charging Current (2) Foldback Holding Current I Impedance of PGOOD Low R PGOOD Threshold PGOOD Delay CTL Delay X CTL Input Current (2) X CTL Input High Threshold X ...
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Pin Descriptions Pin # Pin Name Pin Function 1, 2 PVINA Input supply voltage for the converter power stage 3 AGNDA Ground connection for the internal circuitry — AGNDA needs to be connected to PGNDA directly. Power supply for the ...
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Block Diagram AVINA 4 Oscillator and Slope Generator VOUTA 11 CTL0A 5 Voltage CTL1A 6 Select 7 CTL2A 8 CTL3A SSA 10 AGNDA 3 AVINB 18 Oscillator and Slope Generator 25 VOUTB CTL0B 19 Voltage CTL1B 20 Select 21 CTL2B ...
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Typical Characteristics Circuit Conditions 22µF/6.3V 22µF/6.3V OUT Efficiency °C A 100 3.3V IN OUT 5V OUT V ...
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Typical Characteristics (continued) Circuit Conditions 22µF/6.3V 22µF/6.3V OUT Output Voltage Ripple ( 3.3V OUT V (50mV/div) OUT V (2V/div (2V/div) I (1A/div) SW ...
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Typical Characteristics (continued) Circuit Conditions 22µF/6.3V 22µF/6.3V OUT Output Voltage Ripple ( 5V 3.3V IN OUT OUT V (50mV/div) OUT V (2V/div ...
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Typical Characteristics (continued) Circuit Conditions 22µF/6.3V 22µF/6.3V OUT Start Up (CTL 3.3V IN OUT OUT V (5V/div) CTLx PGOOD (5V/div) V (2V/div) OUT ...
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Typical Characteristics (continued) Circuit Conditions 22µF/6.3V 22µF/6.3V OUT Output Short Circuit 1.5V IN OUT V (5V/div) LX PGOOD (5V/div) V (1V/div) OUT I (5V/div) OUT Time (20µs/div) ...
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Typical Characteristics (continued) Circuit Conditions 22µF/6.3V 22µF/6.3V OUT Transient Response ( 5V OUT VID Transition — No Load V = 5V; V ...
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Applications Information Detailed Description The SC286 is a two channel synchronous step-down PWM (Pulse Width Modulated), DC-DC converter utilizing a 1.6MHz fixed-frequency voltage mode architecture. Both channels are designed to operate in fixed-frequency PWM mode and will enter PSAVE (power ...
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Applications Information (continued) Under this condition, the output voltage will be the product of I and the load resistance. When the load presented CL_HOLD falls below the current limit holding level, the output will charge to the upper PSAVE voltage ...
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Applications Information (continued) To guarantee an operating junction temperature of less than 125°C, Figure 3 shows the maximum allowable total power loss versus temperature. The curve is based upon the junction temperature of either channel reaching a maximum of 125°C. ...
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Applications Information (continued) Soft-Start The soft-start mode is activated for each channel after AVIN reaches it’s UVLO voltage threshold and CTL high to enable the part. Recovery from a thermal shut- down event will also activate the soft start sequence. ...
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Applications Information (continued) PCB Layout Considerations The layout diagram in Figure 5 shows a recommended top-layer PCB for the SC286 and supporting components. Figure 6 shows the bottom layer for this PCB. Fundamental layout rules must be followed since the ...
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Outline Drawing – 4x4 MLPQ-UT28 PIN 1 INDICATOR (LASER MARK) A aaa C A1 NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS THE TERMINALS ...
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Land Pattern – 4x4 MLPQ-UT28 K ( NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. ...
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... Semtech products for any such unauthorized application, the customer shall indemnify and hold Semtech and its officers, em- ployees, subsidiaries, affiliates, and distributors harmless against all claims, costs damages and attorney fees which could arise. Contact Information Semtech Corporation Power Management Products Division 200 Flynn Road, Camarillo, CA 93012 Phone: (805) 498-2111 Fax: (805) 498-3804 www ...