ncp1573 ON Semiconductor, ncp1573 Datasheet
ncp1573
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ncp1573 Summary of contents
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... NCP1573 Low Voltage Synchronous Buck Controller The NCP1573 is a low voltage buck controller. It provides the control for a DC−DC power solution producing an output voltage as low as 0.980 V over a wide current range. The NCP1573−based solution is powered from 12 V with the output derived from a 2−7 V supply ...
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... V PWRGD V LOGIC 0.47 μ PWRGD NCP1573 PGDELAY GATE(L) COMP GATE(H) C12 0.01 μF C13 0.1 μF MAXIMUM RATINGS* Operating Junction Temperature Storage Temperature Range ESD Susceptibility (Human Body Model) Lead Temperature Soldering: Moisture Sensitivity Level Package Thermal Resistance, SO−8 Junction− ...
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ELECTRICAL CHARACTERISTICS C = 0.01 μ 0.1 μF; unless otherwise specified.) PGDELAY COMP Characteristic Error Amplifier V Bias Current FB COMP Source Current COMP Sink Current Reference Voltage COMP Max Voltage COMP Min Voltage Open Loop Gain Unity ...
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ELECTRICAL CHARACTERISTICS (continued 0.01 μ 0.1 μF; unless otherwise specified.) PGDELAY COMP Characteristic PWM Comparator PWM Comparator Offset Ramp Max Duty Cycle Artificial Ramp Transient Response V Input Range FB Oscillator Switching Frequency General Electrical Specifications ...
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GND Error Amp V − 0.980 V − COMP 0.525 V − + Σ Art Ramp 80%, 200 kHz PGDELAY Latch − 0.88 V/0.69 V − R Set Dominant PWM Latch PWM COMP − ...
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TYPICAL PERFORMANCE CHARACTERISTICS Temperature (°C) Figure 3. Supply Current vs. Temperature 0.984 0.983 0.982 0.981 0.980 0.979 0.978 0.977 0.976 Temperature (°C) Figure 5. Reference Voltage ...
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TYPICAL PERFORMANCE CHARACTERISTICS Source Current Temperature (°C) Figure 9. Error Amp Output Currents vs. Temperature 38 GATEH Fall Time 36 GATEH Rise Time GATEL ...
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TYPICAL PERFORMANCE CHARACTERISTICS 13.4 13.1 12.8 12.5 12.2 11.9 11 Temperature (°C) Figure 15. PGDELAY Charge Current vs. Temperature 259 257 255 253 251 Temperature (°C) Figure 17. PGDELAY Discharge Threshold Voltage ...
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... THEORY OF OPERATION The NCP1573 is a simple, synchronous, fixed−frequency, low−voltage buck controller using the V provides a programmable−delay Power Good function to indicate when the output voltage is out of regulation Control Method 2 The V control method uses a ramp signal generated by the ESR of the output capacitors. This ramp is proportional to the AC current through the main inductor and is offset by the DC output voltage ...
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... Variations in supply line or output load conditions will result in changes in duty cycle to maintain regulation. Input Supplies The NCP1573 can be used in applications where supply is available along with a lower voltage supply. Often the lower voltage supply but it can be any voltage less than the 12 V supply minus the required gate drive voltage of the top MOSFET ...
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OUT = load transient; ΔI OUT Δt = load transient duration time; ESL = Maximum allowable ESL including capacitors, circuit traces, and vias; ESR = Maximum allowable ESR including capacitors and ...
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OUT ) V OUT I RIPPLE + ( f OSC )( Peak inductor current is defined as the load current plus half of the peak current. Peak current must be ...
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... Output Switch FETs Output switch FETs must be chosen carefully, since their properties vary widely from manufacturer to manufacturer. The NCP1573 system is designed assuming that n−channel FETs will be used. The FET characteristics of most concern are the gate charge/gate−source threshold voltage, gate capacitance, on−resistance, current rating and the thermal capability of the package ...
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... NCP1573 are that undervoltage lockout and soft start resetting are not included. These features must be absent to allow the NCP1573 to interface in a glitch−free manner with back−up power supplies. A schematic showing a possible system implementation using the NCP1573 is included in Figure 23. Note that an PWRGD 12 V R11 10 k ...
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Providing fast turn−on and turn−off edges to the IC power is very important in minimizing glitching because there is no undervoltage lockout circuitry. For example, if the switcher were powered up and regulating, and the supply began to decrease slowly, ...
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Layout Considerations 2 1. The fast response time of V technology increases the IC’s sensitivity to noise on the V Fortunately, a simple RC filter, formed by the feedback network and a small capacitor (100 pF works well, shown below ...
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... MAXIMUM MOLD PROTRUSION 0.15 (0.006) PER SIDE. 5. DIMENSION D DOES NOT INCLUDE DAMBAR PROTRUSION. ALLOWABLE DAMBAR PROTRUSION SHALL BE 0.127 (0.005) TOTAL IN EXCESS OF THE D DIMENSION AT MAXIMUM MATERIAL CONDITION Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative NCP1573/D ...