SC251EVB SEMTECH [Semtech Corporation], SC251EVB Datasheet
SC251EVB
Related parts for SC251EVB
SC251EVB Summary of contents
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POWER MANAGEMENT Description The SC251 is a synchronous step-down converter designed for use as an adaptive voltage supply for WCDMA RF power amplifi ers (PAs). An analog control input is used to adjust the output voltage dynamically between 0.5V and ...
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POWER MANAGEMENT Absolute Maximum Ratings Exceeding the specifi cations below may result in permanent damage to the device or device malfunction. Operation outside of the parameters specifed in the Electrical Characteristics section is not recommended. Parameter Input Supply Voltage Logic ...
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POWER MANAGEMENT Electrical Characteristics (Cont.) Parameter Symbol Shutdown Current P-Channel Current Limit V Pass-through V DAC Mode Threshold V Pass-through DAC V Mode Hysteresis V Output REF V LDO Dropout REF V Load Current REF V Load Regulation V REF ...
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POWER MANAGEMENT Electrical Characteristics (Cont.) Parameter Symbol Enable Transient Settling Time (1) VDAC Transient Over/Undershoot (1) VDAC Transient Settling Time (1) Pass-Through Transition Over/Undershoot (1) Pass-Through Transition Settling Time (1) Thermal Shutdown Thermal Shutdown Hysteresis Notes: 1) Not tested - ...
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... VMODE 5 T MLPD10: 3X3 10 LEAD Marking Information © 2006 Semtech Corp. Ordering Information SC251MLTRT LX 10 SC251EVB PGND 9 Notes: VOUT 1) Lead-free packaging only. This product is fully WEEE and RoHS compliant Available in tape and reel only. A reel contains 3000 devices. GND 7 6 VDAC ...
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POWER MANAGEMENT Block Diagram GD 3 VIN 1 References VREF 2 GND VDAC PWL 6 Transfer Function VMODE 5 Generator © 2006 Semtech Corp. Current Sense Control Logic PWM Comparator SENSE Error Amp. Oscillator Slope Generator 6 ...
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POWER MANAGEMENT Pin Description Pin# Pin Name Pin Function 1 VIN Input supply pin. A 2.85V LDO reference voltage supply - 10mA max load that can be used as a supply 2 VREF for power amplifi er bias inputs. A ...
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POWER MANAGEMENT Applications Information SC251 Detailed Description The SC251 is a step-down, fi xed frequency pulse-width modulated DC-DC converter designed for use with RF power amplifi ers (PAs) in WCDMA handsets and modules. The output is used to supply DC ...
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POWER MANAGEMENT Applications Information (Cont.) Maximum Load V (V) OUT Figure 3 - Load Profi le-Low Power Mode Maximum Load Minimum Load V (V) OUT Figure 4 - Load Profi le-High Power Mode High Power Mode The SC251 enters high ...
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POWER MANAGEMENT Applications Information (Cont.) bias supply for power amplifi ers. This output provides a regulated 2.85V with output current capability up to 10mA. The 2.85V output is guaranteed for input supply voltages Applications Information (Cont.) in excess of 2.95V. ...
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POWER MANAGEMENT Applications Information (Cont.) output voltage ripple component that is dependent upon this ESR, as can be seen in the following equation: Δ = Δ × OUT ( ESR ) ( L ripple ) Capacitors with X7R ...
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POWER MANAGEMENT Applications Information (Cont.) PCB Layout Considerations Poor layout can degrade the performance of the DC- DC converter and can be a contributory factor in EMI problems, ground bounce and resistive voltage losses. Poor regulation and instability can result. ...
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POWER MANAGEMENT Typical Characteristics Effi ciency vs. Load V =1.8V OUT 100 =3.6V V =4. 0.001 0.010 I (A) OUT Effi ciency vs. Load V =1.5V OUT ...
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POWER MANAGEMENT Typical Characteristics (Cont.) Effi ciency vs. V 100 90 I =100mA OUT 80 I =600mA OUT 0.0 0.5 1.0 1.5 2.0 Vout(V) V vs. I OUT OUT 1.600 1.595 1.590 ...
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POWER MANAGEMENT Typical Characteristics (Cont.) Oscillator Frequency vs. Temperature 1150 1100 1050 1000 950 900 850 0 -40 - Temperature( C) ° R vs. Temperature DSON 0.40 0.35 0.30 0.25 0.20 0.15 0.10 -40 -25 -10 5 ...
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POWER MANAGEMENT Typical Characteristics (Cont.) Enable Startup EN 5V/DIV LX 5V/DIV VOUT 2V/DIV IIN 500mA/DIV 40μs/DIV V Step Response (Passthrough) DAC VDAC 1V/DIV VGD 5V/DIV V IN LOAD = 5Ω VOUT MODE = LP 2V/DIV V DAC LX 5V/DIV 100μs/DIV ...
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POWER MANAGEMENT Typical Characteristics (Cont.) Passthrough Current Limit Operation IOUT 1A/DIV IL 500mA/DIV VOUT 200V/DIV LX 5V/DIV 1ms/DIV Output Ripple Waveform LX 5V/DIV VOUT 10mV/DIV IL 100mA/DIV 200ns/DIV © 2006 Semtech Corp. VEN 2V/DIV VGD 5V/DIV VOUT V = 4.0V ...
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POWER MANAGEMENT Outline Drawing - MLP-10 3x3 A PIN 1 INDICATOR (LASER MARK) aaa C LxN NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS TERMINALS. © 2006 Semtech ...
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POWER MANAGEMENT Land Pattern - MLP-10 3x3 H (C) X NOTES: 1. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. Contact Information Contact Information Phone: (805) 498-2111 Fax: ...