NCP1579 ON Semiconductor, NCP1579 Datasheet
NCP1579
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NCP1579 Summary of contents
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... V. This 8−pin device provides an optimal level of integration to reduce size and cost of the power supply. The NCP1579 provides gate driver design and an internally set 275 kHz oscillator. In addition to the 1 A gate drive capability, other efficiency enhancing features of the gate driver include adaptive non− ...
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0 REF COMP/DIS 7 www.DataSheet4U.com V CC BST FB COMP/DIS TG PHASE BG GND Figure 1. Typical Application Diagram FAULT PWM - OUT S Clock Ramp OSC OSC Figure 2. ...
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PIN FUNCTION DESCRIPTION Pin No. Symbol 1 BST Supply rail for the floating top gate driver. To form a boost circuit, use an external diode to bring the desired input voltage to this pin (cathode connected to BST pin). Connect ...
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ELECTRICAL CHARACTERISTICS 0 V < PHASE < Characteristic Input Voltage Range Boost Voltage Range Supply Current Quiescent Supply Current Boost Quiescent Current Under Voltage Lockout UVLO Threshold UVLO Hysteresis Switching Regulator VFB Feedback ...
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TYPICAL CHARACTERISTICS 5.0 4.7 4.4 4.1 3.8 3 JUNCTION TEMPERATURE (°C) J Figure JUNCTION TEMPERATURE (°C) J Figure ...
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... General The NCP1579 is a PWM controller intended for DC−DC conversion from 5.0 V & buses. The devices have internal gate driver circuit designed to drive N−channel MOSFETs in a synchronous−rectifier buck topology. The output voltage of the converter can be precisely regulated down to 800 mV ±2.0% when the V The switching frequency, is internally set to 275 kHz ...
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... Undervoltage Lockout (UVLO) is provided to ensure that unexpected behavior does not occur when V support the internal rails and power the converter. For the NCP1579, the UVLO is set to permit operation when converting from a 5.0 input voltage. Overcurrent Threshold Setting NCP1579 can easily program an Overcurrent Threshold ranging from 550 mV, simply by adding a resistor (RSET) between BG and GND ...
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Input Capacitor Selection The input capacitor has to sustain the ripple current produced during the on time of the upper MOSFET must have a low ESR to minimize the losses. The RMS value of this ripple is: Iin ...
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... The pole of the compensation network is calculated as, V REF * V OUT REF R 1 100 Thermal Considerations The power dissipation of the NCP1579 varies with the MOSFETs used average MOSFET gate current typically dominates the + V ref control IC power dissipation. The IC power dissipation is − determined by the formula: Where: http://onsemi ...
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... Please note that the capacitors C and C each represent numerous physical IN OUT capacitors desirable to locate the NCP1579 within 1 inch of the MOSFETs, Q1 and Q2. The circuit traces for the MOSFETs’ gate and source connections from the NCP1579 must be sized to handle peak current ...
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... N 0.25 0.50 0.010 S 5.80 6.20 0.228 1.52 0.060 4.0 0.155 1.270 0.050 mm SCALE 6:1 inches ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative INCHES MAX 0.197 0.157 0.069 0.020 0.050 BSC 0.010 0.010 0.050 0.020 0.244 NCP1579/D ...