NCP1575 ON Semiconductor, NCP1575 Datasheet
NCP1575
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NCP1575 Summary of contents
Page 1
... SOIC−8 package. The NCP1575−based solution requires a bias supply and it can convert from a bulk power supply ranging from Conversion from bulk supplies greater than best accomplished by using an external doubler circuit to raise the enhancement voltage for the external NFET switches ...
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... COMP R3 NCP1575 Option C11 0.1 mF Figure Only Applications Diagram 2.5 V Conversion NCP1575 OSC NC COMP 33 k 0.1 mF 0.1 mF Figure 2. 12 V/5 V Applications Diagram, 350 kHz 1.2 V Conversion NCP1575 + + C1 C2 1000 mF/16 V 1000 mF/ 0 0.01 mF GND V FB GATE(L) GATE(H) R5 0.98 V 3.32 k ...
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... NC COMP R3 Option open C11 0.1 mF Figure Only Applications Diagram 2.5 V Conversion NCP1575 + + C1 C2 1000 mF/16 V 1000 mF/16 V C3* 0.033 mF C9 10000 pF GND V FB GATE(L) GATE(H) NCP1575 R5 R6 0.98 V 3.3 k 5.1 k C10 4700 pF http://onsemi.com 3 2 NTD30N02 L2 2 NTD30N02 1000 mF 1000 mF ...
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... COMP Fault Discharge Threshold to Reset UVLO Open Loop Gain Unity Gain Bandwidth PSRR @ 1.0 kHz Output Transconductance Output Impedance 2. Characteristics at temperature extremes are guaranteed via correlation using quality statistical control methods. NCP1575 Rating Junction−to−Case, R qJC Junction−to−Ambient, R qJA V V MAX ...
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... General Electrical Specifications V Supply Current CC Start Threshold Stop Threshold Hysteresis 3. Characteristics at temperature extremes are guaranteed via correlation using quality statistical control methods. 4. Guaranteed by design. Not tested in production. NCP1575 (0 C < T < 125 C, 9.0 V < V < GATE(H) Test Conditions 1.0 V < GATE(L), GATE(H) < V − ...
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... Power supply return. UVLO Comp V − − 8.5 V/7.5 V GND − − 0.25 V Error Amp V − − 0.98 V COMP S − + 0.465 V NCP1575 FUNCTION UVLO Latch Set Dominant PWM Comp PWM Latch − Reset Dominant Oscillator 200 kHz Figure 4. Block Diagram http://onsemi.com 6 to ground OSC V ...
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... R Value (kW) OSC Figure 7. Oscillator Frequency vs 100 R Value (kW) OSC Figure 9. Artificial Ramp at 50% Duty Cycle vs. R Value OSC NCP1575 216 214 212 210 208 206 204 202 80 100 120 0 20 Figure 6. Oscillator Frequency vs. Temperature 300 295 290 285 ...
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... Temperature ( C) Figure 13. V Bias Current vs. Temperature FB 3.5 COMP Maximum Voltage 3.0 2.5 2.0 COMP Minimum 1.5 Voltage 1.0 0.5 Threshold Voltage Temperature ( C) Figure 15. COMP Voltages vs. Temperature NCP1575 8.6 8.4 8.2 8.0 7.8 7.6 7.4 7.2 100 120 0 20 Figure 12. Undervoltage Lockout Thresholds vs 100 120 0 20 Figure 14. Error Amp Output Currents vs. Temperature 1 ...
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... Temperature ( C) Figure 17. GATE Output Rise and Fall Times vs. Temperature ( Figure 19. Artificial Ramp at 50% Duty Cycle NCP1575 55 50 GATEH to GATEL Delay Time 100 120 0 20 Figure 18. GATE Nonoverlap Times vs. Temperature ...
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... This feature prevents stress to the power components and limits output voltage overshoot during startup. As power is applied to the regulator, the NCP1575 undervoltage lockout circuit (UVL) monitors the IC’s supply voltage (V holds the GATE(H) output low and the GATE(L) output high until V function of 1 ...
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... Solve the equation above for the value of R1. Choosing the Oscillator Frequency The NCP1575 has an oscillator that is trimmed to 200 kHz at the factory. The NCP1575 will operate at this frequency without the addition of any external components. However, the oscillator is user−programmable with a single resistor. ...
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... Similarly, the maximum allowable ESL is calculated from the following formula: DV ESL ESL MAX + DI NCP1575 Selection of the Input Inductor A common requirement is that the buck controller must not disturb the input voltage. One method of achieving this is by using an input inductor and a bypass capacitor. The ...
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... The response times for both increasing and decreasing current steps are shown below. T RESPONSE(INCREASING RESPONSE(DECREASING) + NCP1575 Inductor value selection also depends on how much output ripple voltage the system can tolerate. Output ripple voltage is defined as the product of the output ripple current and the output filter capacitor ESR ...
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... Output Switch FETs Output switch FETs must be chosen carefully, since their properties vary widely from manufacturer to manufacturer. The NCP1575 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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... This capacitor should be located as close as possible to the IC. 2. The COMP capacitor should be connected via its own path to the IC ground. The COMP capacitor is sensitive to the intermittent ground drops caused NCP1575 by switching currents. A separate ground path will reduce the potential for jitter. line. 3. The V FB should be located as close as possible to the IC ...
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... D 0.33 0.51 0.013 0.020 G 1.27 BSC 0.050 BSC H 0.10 0.25 0.004 0.010 J J 0.19 0.25 0.007 0.010 K 0.40 1.27 0.016 0.050 0.25 0.50 0.010 0.020 S 5.80 6.20 0.228 0.244 mm inches ON Semiconductor Website: http://onsemi.com Order Literature: http://www.onsemi.com/litorder For additional information, please contact your local Sales Representative. NCP1575 ...