ncp1423 ON Semiconductor, ncp1423 Datasheet
ncp1423
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ncp1423 Summary of contents
Page 1
... Sync−Rect PFM Step−Up DC−DC Converter with True−Cutoff and Ring−Killer NCP1423 is a monolithic micropower high frequency step−up switching converter IC specially designed for battery operated hand−held electronic products. It integrates Synchronous Rectifier for improving efficiency as well as eliminating the external Schottky Diode ...
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... Moisture Sensitivity Level: MSL 1 per IPC/JEDEC standard: J−STD−020A. 5. Measured on approximately Cu. NCP1423 100k EN LBO REF LBI ON FB ADEN OFF GND LX 5.6 mH OUT BAT 10 mF NCP1423 C * Optional Figure 1. Typical Operation Circuit Description = 25°C A http://onsemi.com 2 Low battery open drain output R3 Low battery R4 sense input IN = 3.3 V. OUT is < ...
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... ADEN Threshold ( 3.3 V) BAT ADEN Input Current ADEN Switch Resistance Thermal Shutdown Temperature (Note 7) Thermal Shutdown Hysteresis (Note 7) 6. Value depends on voltage OUT 7. Values are guaranteed by design. NCP1423 v 85°C for min/max values unless otherwise noted.) A Symbol IN_MIN ...
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... ZLC 0 Chip Enable 1 CONTROL LOGIC − PFM 1.2 V REF 2 Voltage Reference 0 LBI − 9 NCP1423 + − TRUE CUTOFF CONTROL _ZCUR _TSDON V DD _MSON _MAINSW2ON GND _CEN V _PFM _MAINSWOFD _SYNSW2ON GND _SYNSWOFD _V REFOK _ILIM + − + GND Figure 2. Detailed Block Diagram http://onsemi.com ...
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... T , AMBIENT TEMPERATURE (°C) A Figure 5. Reference Voltage vs. Temperature 0.56 0.54 0.52 0.50 0.48 0.46 0.44 −50 − AMBIENT TEMPERATURE (°C) A Figure 7. Low Battery Detect Voltage vs. Temperature NCP1423 1.25 1.23 1.21 1.19 1.17 1.15 1.13 100 1000 1.5 2 Figure 4. Reference Voltage vs. Voltage at OUT Pin 1 3.3 V OUT 0.8 0.6 0 3.3 V 0.2 OUT = 0 REF I ...
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... T , AMBIENT TEMPERATURE (°C) A Figure 11. ADEN Pin Input Current vs. Temperature 2.0 1.8 1.6 1.4 1.2 1.0 0.8 −50 − AMBIENT TEMPERATURE (°C) A Figure 13. L Switch Maximum ON Time vs. X Temperature NCP1423 15 3.3 V OUT 12.5 10.0 7.5 5.0 2.5 0.0 75 100 −50 − AMBIENT TEMPERATURE (°C) A Figure 10. Shutdown Current vs. Temperature 0. 3.3 V OUT 0.52 0.51 0.50 0.49 0.48 ...
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... 3.3 V OUT = 10 mF OUT 5.6 mH 25° 1.2 V, 1.5 V, 2 100 I , OUTPUT LOADING CURRENT (mA) LOAD Figure 19. Efficiency vs. Load Current NCP1423 1.6 1.4 1.2 1.0 0.8 0.6 0 100 0 I LOAD Figure 16. Minimum Startup Battery Voltage vs 2 − 5.6 mH ...
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... Lower Trace: Voltage at LBO Pin, 1.0 V/Division Figure 23. Low Battery Detect Upper Trace: Output Voltage Ripple, 100 mV/Division Middle Trace: Voltage at Lx pin, 2.0 V/Division Lower Trace: Inductor Current, 500 mA/Division = 50 mA 5 OUT LOAD Figure 25. Discontinuous Conduction Mode Switching Waveform NCP1423 15 12 100 mA 7.5 5.0 2.5 1.8 2.1 2.3 2.5 V ...
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... Lower Trace: Output Current, 50 mA/Division Middle Trace: Enable Pin Waveform, 1.0 V/Division = 3 5 OUT IN Figure 31. Startup Waveform (ADEN Disabled) NCP1423 Upper Trace: Output Voltage Ripple, 50 mV/Division Lower Trace: Battery Voltage 1 1 5.6 mH mA) (V LOAD IN = 3.3 V Figure 28. Line Transient Response For V ...
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... REF is not loaded. If REF is loaded, 1.0 mF capacitor at REF pin is needed. True−Cutoff The NCP1423 has a True−Cutoff function controlled by the EN pin (Pin 1). Internal circuitry can isolate the current through the body diode of switch M2 to load. Thus, it can eliminate leakage current from the battery to load in shutdown mode and significantly reduces battery current consumption during shutdown ...
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... R4 and the relationship is given by LBI + 0.5 V where R3 and R4 are the upper and lower divider resistors respectively. Inductor Selection The NCP1423 is tested to produce optimum performance with a 5.6 mH inductor 1 supplying an output current up to 200 mA. For other input / output requirements, inductance in the range can be used according to end application specifications ...
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... Below a simple method base on the most basic first order equations to estimate the inductor and capacitor values for NCP1423 operate in Continuous Conduction Mode (CCM) is introduced. The component value set can be used as a starting point to fine− ...
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... MIN MAX A 2.90 3.10 0.114 0.122 B 2.90 3.10 0.114 0.122 C 0.95 1.10 0.037 0.043 D 0.20 0.30 0.008 0.012 G 0.50 BSC 0.020 BSC H 0.05 0.15 0.002 0.006 J 0.10 0.21 0.004 0.008 K 4.75 5.05 0.187 0.199 L 0.40 0.70 0.016 0.028 10X 5.28 0.208 mm inches ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative NCP1423/D ...