ncp1522 ON Semiconductor, ncp1522 Datasheet
ncp1522
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ncp1522 Summary of contents
Page 1
... High-Ef ficiency, Low Quiescent Current, Adjustable Output Voltage Step-Down Converter The NCP1522 step-down PWM DC-DC converter is optimized for portable applications powered from one cell Li-ion or three cell Alkaline/NiCd/NiMH batteries. The device is available in an adjustable output voltage from 0 3 uses synchronous rectification to increase efficiency and reduce external part count. ...
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... Figure 2. Efficiency vs. Output Current Vbattery VIN PWM/BURST 1 CONTROL 4.7 mF GND 2 LOGIC CONTROL Enable EN & THERMAL 3 SHUTDOWN Figure 3. Simplified Block Diagram NCP1522 V = 3.3 V out 25°C A 100 200 300 400 500 I (mA) out ILIMIT FB 4 REFERENCE VOLTAGE http://onsemi ...
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... Latchup current maximum rating per JEDEC standard: JESD78. 3. This device series contains ESD protection and exceeds the following tests: Human Body Model (HBM) per JEDEC standard: JESD22-A114. Machine Model (MM) per JEDEC standard: JESD22-A115. NCP1522 Description Power Supply Input for Analog Ground connection for the NFET Power Stage and the Analog Sections of the IC ...
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... EN << H >> Input Current 3.6 V Soft-Start Time Thermal Shutdown Threshold Thermal Shutdown Hysteresis 4. The overall output voltage tolerance depends upon the accuracy of the external resistor (R1, R2). NCP1522 (Typical values are referenced +25°C, Min and Max values are referenced -40° 3 ...
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... Figure 6. Shutdown Current vs. Supply Voltage 100 -40° 100 200 300 I , OUTPUT CURRENT (mA) OUT Figure 8. Efficiency vs. Output Current ( 3.6 V) OUT IN NCP1522 100 OUT 10 0 5.2 5.7 -40 -20 Figure 5. Quiescent Current vs. Temperature 100 ...
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... Figure 10. Efficiency vs. Output Current ( 3.6 3.4 3.2 3.0 2.8 2 300 mA OUT 2.4 -40 - TEMPERATURE (°C) Figure 12. Frequency vs. Temperature 2.0 1.5 1.0 0.5 0.0 0 0.2 0.4 0.6 0 ENABLE INPUT VOLTAGE (V) IN Figure 14. Output Voltage vs. Enable Input Pin Voltage NCP1522 3.6 3.4 3.2 3 3.3 V OUT 2.8 2.6 2.4 2.7 3.2 500 600 Figure 11. Frequency vs. Input Voltage 3.0 2 0.9 V OUT 2.0 1.5 V OUT 1 5 0.5 0 3.3 V OUT -0.5 -1 ...
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... OUT 1.0 0 300 mA OUT 0.0 -0 600 mA OUT -1 -2.0 - TEMPERATURE (°C) Figure 16. Output Voltage Accuracy (V = 0.9 V) OUT 2.0 1.5 1.0 0.5 0.0 -0.5 -1.0 -1.5 -2.0 -50 NCP1522 2.0 1.5 1.0 0.5 0.0 -0.5 -1 -2.0 100 150 -50 Figure 17. Output Voltage Accuracy I = 300 mA OUT I = 100 mA OUT I = 600 mA OUT 100 TEMPERATURE (°C) Figure 18. Output Voltage Accuracy (V = 3.3 V) OUT http://onsemi ...
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... Figure 19. Load Transient Response in PWM Operation ( V/Div V OUT 500 mV/Div 100 ms/Div Figure 21. Soft Start Time ( NCP1522 V OUT 20 mV/Div Figure 20. Load Transient Response in PWM Operation (V 2.5 ms/Div Figure 22. Short Circuit Protection (V http://onsemi.com 8 I OUT 200 mA/Div 10 ms/Div = 3 ...
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... V or higher. PWM Operating Mode In this mode, the output voltage of the NCP1522 is regulated by modulating the on-time pulse width of the main switch fixed frequency of 3.0 MHz. The switching of the PMOS Q1 is controlled by a flip-flop ...
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... When the short circuit condition is removed, the device returns to the normal mode of operation. Soft-Start The NCP1522 uses soft-start (300 ms Typ) to limit the inrush current when the device is initially enabled. Soft-start is implemented by gradually increasing the reference voltage until it reaches the full reference voltage. ...
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... JMK212BY475MG TDK C2012X5ROJ475KB C1632X5ROJ475KT Output L-C Filter Design Considerations The NCP1522 is built in 3.0 MHz frequency and uses voltage mode architecture. The correct selection of the output filter ensures good stability and fast transient response. Due to the nature of the buck converter, the output L-C filter must be selected to work with internal compensation. ...
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... SW C OUT In PFM mode (at light load), the output voltage is regulated by pulse frequency modulation. The output voltage ripple is independent of the output capacitor value set by the threshold of PFM comparator. NCP1522 Table 4. List of Output Capacitor Murata Taiyo Yuden LPO3010 TDK Feed-Forward Capacitor Selection The feed-forward capacitor sets the feedback loop response and is critical to obtain good loop stability ...
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... Separate the feedback path of the output voltage from the power path. Keep this path close to the NCP1522 circuit. And also route it away from noisy components. This will prevent noise from coupling into the voltage feedback trace. 4. Place the DC-DC converter away from noise sensitive circuitry, such as RF circuits ...
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... U1 J1 VFVIN VIN GND 4.7 mF Power NCP152x 0 NCP1522 2 4 CON3 220 K BNCH 0 0 Figure 27. Schematics Figure 28. Silkscreen Layer http://onsemi.com 14 OUTPUT VOUT 220 R R2 220 ...
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... NCP1522 Figure 29. Board Layout (Top View) Figure 30. Board Layout (Bottom View) http://onsemi.com 15 ...
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... Bill of Materials Item Part Description 1 NCP1522 DC-DC Converter 4.7 mF Ceramic Capacitor 2 6.3 V X5R Ceramic Capacitor 50 V COG 4 SMD Resistor 220 K 5 SMD Inductor 6 I/O Connector can be plugged by BLZ5.08/2 (Weidmüller reference) 7 Jumper Header vertical mount 3*1, 2. Jumper Connector, 400 mils NCP1522 Ref PCB Footprint ...
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... IN THIS LOCATION. TRIMMED LEAD NOT TO EXTEND MORE THAN 0.2 FROM BODY. MILLIMETERS DIM MIN MAX A 3.00 BSC B 1.50 BSC C 0.90 1.10 D 0.25 0.50 G 0.95 BSC H 0.01 0.10 J 0.10 0.26 K 0.20 0.60 L 1.25 1. 2.50 3.00 2.4 0.094 mm SCALE 10:1 inches ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your loca Sales Representative NCP1522/D ...