NCP5318 ON Semiconductor, NCP5318 Datasheet
NCP5318
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NCP5318 Summary of contents
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... NCP5318 Two/Three/Four−Phase Buck CPU Controller The NCP5318 provides full−featured and flexible control conforming to the Intel® VRM 10.1 specification for high−performance CPUs. The IC can be programmed as a two−, three− or four−phase buck controller, and the per−phase switching frequency can be as high as 1 ...
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... VID5 VID5 VCC 31 VID0 VID0 32 VID1 VID1 1 VID2 VID2 2 VID3 VID3 3 VID4 VID4 29 VID_PWRGD ENABLE 7 VCC_PWRGD PWRGD 9 SGND RS 15K 4 PWRLS NCP5318FTR2 RP 20K 5 VFFB 11 VFB RF2* RF1 15K NTC 2K RFB 1.5K RDRP 3.25K 10 VDRP RD1 1K CD1 RF 1nF OPEN 12 COMP ILIM ROSC CF OPEN 24 CA1 ...
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... V 7.0 V −0.3 V 7.0 V −0 −0 −0 −0 −0 −0.3 V http://onsemi.com 3 Value Unit 150 NCP5318FTR2 230 peak 260 peak −65 to 150 2.0 NCP5318FTR2 °C SOURCE SINK 1.0 mA 1.0 mA 1.0 mA 1.0 mA 1.0 mA 1.0 mA 1.0 mA 1 1.0 mA 1.0 mA 1.0 mA − 1 ...
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ELECTRICAL CHARACTERISTICS C = 0.1 mF 0.1 mF 95.3 kW, V(I SS VCC ROSC VOLTAGE IDENTIFICATION (VID) Voltage Identification Bits (Connect V to COMP, measure COMP ID4 ID3 ID2 0 1 ...
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ELECTRICAL CHARACTERISTICS C = 0.1 mF 0.1 mF 95.3 kW, V(I SS VCC ROSC VOLTAGE IDENTIFICATION (VID) (continued) Voltage Identification Bits (Connect V to COMP, measure COMP ID4 ID3 ID2 1 ...
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ELECTRICAL CHARACTERISTICS C = 0.1 mF 0.1 mF 95.3 kW, V(I SS VCC ROSC Characteristic VID Inputs Input Threshold VID Pin Current SGND Bias Current SGND Voltage Compliance Range Power Good Upper Threshold, Offset from No ...
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ELECTRICAL CHARACTERISTICS (continued 0.1 mF 0.1 mF 95.3 kW, V(I SS VCC ROSC Characteristic GATES High Voltage Low Voltage Rise Time GATE Fall Time GATE Oscillator Switching Frequency R Voltage OSC Phase Delay, 3 ...
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PIN DESCRIPTION Pin No. Pin Symbol Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á Á 1−3, V −V DAC VID Inputs ID0 ID5 30−32 Á Á Á Á Á Á Á Á ...
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VFB SS 6−BIT DAC VID4 VID4 VID3 VID3 DAC VID2 VID2 VID1 VID1 VID0 VID0 VID5 VID5 111111 SGND REF PWRLS RAMP4 ROSC ROSC RAMP3 RAMP2 RAMP1 CLK1 CLK2 CS4P CLK3 CLK4 OSCILLATOR − VFFB 0.62 V CURRENT SENSE CS1P ...
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TYPICAL PERFORMANCE CHARACTERISTICS 0.50 0.40 0.30 VID = 101101 0.20 VID = 111101 0.10 0.00 −0.10 −0.20 VID = 010101 −0.30 −0.40 −0. TEMPERATURE (°C) Figure 3. DAC Variation versus Temperature 245 240 235 230 225 ...
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TEMPERATURE (°C) Figure 9. V versus Temperature ROSC TEMPERATURE (°C) ...
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TYPICAL PERFORMANCE CHARACTERISTICS 3.41 3.40 3.39 3.38 3.37 3.36 3.35 3.34 3. TEMPERATURE (°C) Figure 13. CS Amp to I LIM Temperature 31.0 30.5 30.0 29.5 29.0 28.5 28.0 27.5 27.0 26.5 26.0 25.5 0 ...
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V CC Enable V Fault REF UVLO Fault Fault Reset Fault Latch Fault DRVON SS COMP V OUT I OUT PWRGD Figure 16. Operating Waveforms http://onsemi.com 13 ...
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... Enhanced V topology which combines the fast transient response of the original V the load current sharing characteristic of peak current−mode control. The NCP5318 can be operated as an interleaved two/three/four−phase controller. sensing is incorporated in order to more easily achieve effective current sharing. Converter output is regulated to a voltage corresponding to the logic states at six digital inputs ...
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... GATEx is low, that phase cannot respond until the next start of its oscillator cycle. Therefore, the NCP5318 will take, at most, the off−time of the oscillator to respond to disturbances. With multiple phases, the time to respond to disturbances is significantly reduced due to the ...
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For the converter described above with 4 phases and 85% efficiency at 100 A full load, the Error Amplifier output changes by: 3.0 V 100 A DV COMP + 14.8 ...
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Inductive Current Sensing For lossless sensing, current can be measured across the inductor as shown in Figure 19. In the diagram the output inductance and R is the inherent inductor resistance compensate the current sense signal, ...
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Transient Response and Adaptive Voltage Positioning For applications with fast transient currents, the output filter is frequently sized larger than ripple currents require in order to reduce voltage excursions during load transients. In addition, adaptive voltage positioning can reduce peak−peak ...
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... DRVON will then low state and stay low until the part is enabled or an OVP is detected. Digital to Analog Converter (DAC) The output voltage of the NCP5318 is set by means of a 6−bit, 0.5% DAC. The VID pins must be pulled high externally. A 1.0 kW pullup to a maximum of 3 recommended to meet Intel specifications ...
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... Adjusting the Number of Phases The NCP5318 is designed with a selectable−phase architecture. Designers may choose any number of phases up to four. The phase delay is automatically adjusted to match the number of phases that will be used. This feature allows the designer to select the number of phases required for a particular application. Four− ...
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Output Inductor Selection The output inductor is a very critical component in the converter because it directly affects the choice of other components and affects both the steady−state and transient performance of the converter. When selecting an inductor, the ...
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The following equations will determine the maximum and minimum currents delivered by the input capacitors: I Lo,MAX I C,MAX + * I IN,AVG h I Lo,MIN I C,MIN + * I IN,AVG the maximum output inductor current: ...
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MAX dI/dt occurs in first few PWM cycles Vi 470 nH NB × − ESR /NB IN Current changes slowly in the input inductor so the ...
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I is the RMS value of the current in the control RMS,CNTL MOSFET: I RMS,CNTL + (D (I Lo,MAX Lo,MAX I Lo,MIN ) I is the maximum output inductor current: Lo,MAX I O,MAX ) ...
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As with any power design, proper laboratory testing should be performed to insure the design will dissipate the required power under worst case operating conditions. Variables considered during testing should include maximum ambient temperature, minimum airflow, maximum input voltage, maximum ...
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Adaptive Voltage Positioning Two resistors program the Adaptive Voltage Positioning (AVP): R and R . These components form a resistor FB DRP R CS1 L1 C CS1 CSx Lx C CSx CS1 L1 ...
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Resistor R is connected between the controller load, this resistor will conduct the very small internal bias current of the V R should be kept below avoid output voltage FB error due ...
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... Since the current information is a part of the control loop, better stability is achieved if the current information is accurate and noise−free. The NCP5318 uses differential current sense amplifiers to achieve the best possible performance. Two sense lines are routed for each phase, as shown in Figure 29 ...
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... This voltage can be programmed by a resistor divider O L from the R = 1.6 mW CSx Figure 37. Programming the Current Limit When the NCP5318 is powered up, the R 1.0 V. This allows the user to determine the resistor divider above by Where R TOTAL http://onsemi.com 29 pin voltage can be calculated by: ...
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−T− DETAIL −Z− −AB− SEATING −AC− PLANE 0.10 (0.004) AC NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: MILLIMETER. 3. DATUM PLANE ...
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... N. American Technical Support: 800−282−9855 Toll Free USA/Canada Europe, Middle East and Africa Technical Support: Phone: 421 33 790 2910 Japan Customer Focus Center Phone: 81−3−5773−3850 http://onsemi.com 31 ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative NCP5318/D ...