SC198 Semtech, SC198 Datasheet
SC198
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SC198 Summary of contents
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... The SC198 uses a single control logic block for the two converters, but their controls can be set independently. The SC198 employs a fl exible clocking scheme that allows the user to use the fi ...
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... LXB θ - 150 J T -65 to +150 S T 260 PKG V 2 ESD = 25°C. A Min Typ 2 300mA OUT 0.9 IN 0.1 0.1 -2 0.1 SC198 Units ºC/W ºC ºC ºC °C kV Max Units 5 0.2 %/V 0.0008 %/ μA 1 μA 1 μA μA ...
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... See Output Voltage Options table in the Application Information section. (2) For ENA, ENB, SYNC, CTLA0, CTLA1, CTLA2, CTLB0, CTLB1, CTLB2. © 2007 Semtech Corp. Conditions 100mA LXA LXB 100mA LXA LXB HI Decreasing SC198 www.DataSheet4U.com Min Typ Max Units 0.35 Ω 0.25 Ω 0.85 1.1 1.25 MHz 1.25 MHz 0.75 MHz 145 ° ...
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... Semtech Corp. Ordering Information SC198MLTRT 16 VINB 15 Notes: (1) Available in tape and reel only. A reel contains 3,000 devices. LXB 14 (2) Available in lead-free package only. Device is WEEE and RoHS compliant. GNDB 13 VOUTB 12 CTLB0 SC198 www.DataSheet4U.com DEVICE PACKAGE MLPQ-20 (1)(2) SC198EVB Evaluation Board www.semtech.com (1) ...
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... Oscillator synchronization input - connect to VIN for forced PWM mode, ground for power-save mode or connect to an external clock for frequency synchronization. Reference supply input Not connected Enable pin for output A Thermal pad for heatsinking purposes — connect to ground plane using multiple vias — not connected internally 5 SC198 www.DataSheet4U.com (1) (1) (1) (1) (1) (1) ...
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... Amp B VREF1 VREF1 PWM PWM Comp Comp Switching Control Logic Error Error Amp A Amp B VREF1 Voltage VREF2 References VREF3 6 SC198 www.DataSheet4U.com Current Amp P Limit Amp N Limit Amp VREF2 VREF3 Voltage Select GNDR www.semtech.com VINB LXB GNDB ENB VOUTB CTLB0 CTLB1 CTLB2 ...
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... Semtech Corp. Programmable Output Voltage The SC198 has three control pins per output to allow the user to select a voltage level from eight predetermined output voltage levels (see Table A, Output Voltage Options below). The output voltage can be selected at any time, including while the output is enabled and loaded. Table A — ...
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... The device sets a maximum peak current in PSAVE mode, and then detects when V load increasing above the level that the peak current will support. For the SC198 to exit PSAVE mode, the load must be increased, which causes V to decrease until the PSAVE OUT exit threshold is reached ...
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... POWER MANAGEMENT Applications Information (Cont.) Inductor Selection The SC198 was designed for optimum performance when using a 4.7μH inductor. The magnitude of the inductor current ripple is dependent on the inductor value and can be determined by the following equation OUT OUT ΔI = ——— ...
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... Semtech Corp. Rated Value μH DCR Ω Current A (1) 4.7 0.20 4.7 0.11 4.7 0.098 4.7 0.072 Value μF Rated Voltage VDC SC198 www.DataSheet4U.com Tolerance Dimensions % (L×W×H) mm 1.1 ±20 6.60 × 5.50 × 1.10 2.10 ±20 5.87 × 4.89 × 3.81 1.0 ± 1.32 ±20 4.7 × 4.7 × 3.0 Type Case Size 6.3 ...
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... Route the output voltage feedback path away from inductor and LX node to minimize noise and magnetic interference. 3. Use a ground plane to further reduce noise interference on sensitive circuit nodes. LXA GND VOUTA Note: Control pin routings are not shown. © 2007 Semtech Corp. VIN CinR CinA SC198 11 SC198 www.DataSheet4U.com CinB LXB GND VOUTB www.semtech.com ...
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... OUT -0.2 -0.4 -0.6 -0.8 4.7 5.1 5.5 12 www.DataSheet4U.com Effi ciency vs. Load @ 3. 1.8V PSAVE OUT PSAVE OUT 1.8V PWM OUT PWM OUT 0 0.001 0.01 0.1 Load (A) Oscillator Frequency vs. Input Voltage 85°C 25°C -40°C 2.7 3.1 3.5 3.9 4.3 4.7 Input (V) Load Regulation at 3.6V (PWM 0.8 0.6 0.4 V OUT 0 OUT -1 0.001 0.01 0.1 Load (A) www.semtech.com SC198 IN ENA=ENB=VIN 1 5.1 5.5 = 1.8V 1 ...
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... OUT 20mV/div 10mV/div 2.0V/div 50mV/div 50mV/div 2V/div 13 www.DataSheet4U.com Effi ciency vs. Line @ OUT 30mA PSAVE 30mA PWM 300mA Load 2.7 3.7 4.7 Input (V) Output Ripple for V = 3.6V and 1. 10mA OUT OUT VIN VOUT LX 400ns/div PSAVE @ 30mA Load VIN VOUT LX 4μs/div www.semtech.com SC198 ...
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... Semtech Corp. = 22μF OUT 200mV/div VIN 200mV/div VOUT 5.0V/div LX 200mA/div IOUT Input Transient Step from 3.6V to 3.1V VIN 500mV/div 20mV/div VOUT 50mV/div VOUTA CTL0 1 and 2 2V/div 14 SC198 www.DataSheet4U.com Transient Step in PSAVE 400μs/div 1ms/div Output Transient in PSAVE 2ms/div www.semtech.com C ...
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... D/2 15 www.DataSheet4U.com DIMENSIONS INCHES MILLIMETERS MIN NOM MAX MIN NOM MAX A .031 .040 0.90 1.00 .035 0.80 .000 .001 .002 0.00 0.02 0. (.008) (0.20) b .007 0.25 0.30 .010 .012 0.18 D .153 .157 .161 3.90 4.00 4.10 2.70 .100 .106 .110 2.55 2.80 E .153 .157 .161 3.90 4.00 4.10 e .020 BSC 0.50 BSC L .011 .016 .020 0.30 0.40 0. .004 0.10 .004 0.10 www.semtech.com SC198 ...
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... Phone: (805) 498-2111 Fax: (805) 498-3804 © 2007 Semtech Corp. K DIM Semtech Corporation Power Management Products Division 200 Flynn Road, Camarillo, CA 93012 www.semtech.com 16 SC198 www.DataSheet4U.com DIMENSIONS INCHES MILLIMETERS (.155) (3.95) .122 3.10 .106 2.70 .106 2.70 .021 0.50 .010 0.25 .033 0.85 .189 4.80 ...