ncp1421 ON Semiconductor, ncp1421 Datasheet
ncp1421
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ncp1421 Summary of contents
Page 1
... Step−Up DC−DC Converter with True−Cutoff and Ring−Killer NCP1421 is a monolithic micropower high−frequency step−up switching converter IC specially designed for battery−operated hand−held electronic products up to 600 mA loading. It integrates Sync−Rect to improve efficiency and to eliminate the external Schottky Diode. High switching frequency (up to 1.2 MHz) allows for a low profile, small− ...
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... V Chip Enable − PFM REF Voltage Reference 4 1. LBI/EN − 2 NCP1421 ZLC + − TRUE CUTOFF CONTROL CONTROL LOGIC _ZCUR _TSDON V DD _MSON _MAINSW2ON GND _CEN _PFM _MAINSWOFD _SYNSW2ON _SYNSWOFD _V REFOK _ILIM + − + GND Figure 1. Detailed Block Diagram http://onsemi.com ...
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... Machine Model (MM) 200 V per JEDEC standard: JESD22−A115. *Except OUT pin, which is 100 V. 2. The maximum package power dissipation limit must not be exceeded. T J(max qJA 3. Latchup Current Maximum Rating: 150 mA per JEDEC standard: JESD78. 4. Moisture Sensitivity Level: MSL 1 per IPC/JEDEC standard: J−STD−020A. NCP1421 Description is < 1.20 V. LBO is high impedance in LBI = 3.3 V. OUT Symbol ...
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... EN Pin Shutdown Threshold ( Thermal Shutdown Temperature (Note 7) Thermal Shutdown Hysteresis (Note 7) 5. Loading capability increases with V OUT. 6. Design guarantee, value depends on voltage Values are design guaranteed. NCP1421 = 25 C for typical value, − 3 OUT A Symbol V V OUT ...
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... AMBIENT TEMPERATURE, T Figure 4. Reference Voltage vs. Temperature 1.0 0.9 0.8 0.7 0.6 0.5 −40 − AMBIENT TEMPERATURE, T Figure 6. L Switch Max. ON Time vs. Temperature X NCP1421 1.220 REF 2.0 V REF 1.210 A 1.200 1.190 1.180 100 1000 1.5 2 /mA Figure 3 ...
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... 5.0 V OUT OUT T = 25_C 100 OUTPUT LOADING CURRENT, I Figure 12. Efficiency vs. Load Current NCP1421 100 3 5.0 V OUT OUT T = 25_C A 50 1000 1 /mA OUTPUT LOADING CURRENT, I LOAD Figure 9 ...
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... BATTERY INPUT VOLTAGE, V Figure 16. Battery Input Voltage vs. Output Ripple Voltage 15 12.5 10 7.5 5.0 2.5 1.5 2.0 2.5 3.0 3.5 INPUT VOLTAGE AT OUT PIN, V Figure 18. No Load Operating Current vs. Input Voltage at OUT Pin NCP1421 2 5.0 V OUT L = 5.6 mH − 2 OUT T = 25_C A − ...
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... V, I OUT LOAD Upper Trace: Output Voltage Ripple, 50 mV/Division Lower Trace: Load Current 500 mA/Division LOAD Figure 24. Load Transient Response For V NCP1421 = OUT IN OUT Upper Trace: Output Voltage Ripple, 20 mV/Division Lower Trace: Voltage at LX pin, 1.0 V/Division Figure 21. Continuous Conduction Mode = 1 2.5 V ...
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... If REF is loaded, a 1.0 mF capacitor at the REF pin is needed. True−Cutoff The NCP1421 has a True−Cutoff function controlled by the multi−function pin LBI/EN (pin 2). 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 reduce battery current consumption during shutdown ...
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... R3 and R4. The relationship is given by 1.20 V where R3 and R4 are the upper and lower divider resistors respectively. Inductor Selection The NCP1421 is tested to produce optimum performance with a 5.6 mH inductor 2.5 V and V IN supplying an output current up to 600 mA. For other input/output requirements, inductance in the range can be used according to end application specifications ...
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... The following is a simple method based on the basic first−order equations to estimate the inductor and capacitor values for NCP1421 to operate in Continuous Conduction Mode (CCM). The set component values can be used as a starting point to fine tune the application circuit performance ...
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... Practically, a capacitor that is one level larger is used to accommodate factors not taken into account in the calculations. Therefore, a capacitor value selected. The NCP1421 is internally compensated for most applications, but in case additional compensation 16 14 ...
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... Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. NCP1421 PACKAGE DIMENSIONS Micro8 DM SUFFIX CASE 846A−02 ISSUE F NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: MILLIMETER. ...
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... USA/Canada Japan: ON Semiconductor, Japan Customer Focus Center 2−9−1 Kamimeguro, Meguro−ku, Tokyo, Japan 153−0051 Phone: 81−3−5773−3850 http://onsemi.com 14 ON Semiconductor Website: http://onsemi.com Order Literature: http://www.onsemi.com/litorder For additional information, please contact your local Sales Representative. NCP1421/D ...