NCP3170AGEVB ON Semiconductor, NCP3170AGEVB Datasheet
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NCP3170AGEVB
Specifications of NCP3170AGEVB
Related parts for NCP3170AGEVB
NCP3170AGEVB Summary of contents
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NCP3170 Synchronous PWM Switching Converter The NCP3170 is a flexible synchronous PWM Switching Buck Regulator. The NCP3170 operates from 4 sourcing and is capable of producing output voltages as low as 0.8 ...
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EN UVLO POR Soft Start Reference Σ ORing Circuit + + FB − − COMP Soft Start Complete + − 998 mV + − 867 mV − + 728 mV PG AGND PIN FUNCTION DESCRIPTION Pin Pin Name 1 PGND ...
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ABSOLUTE MAXIMUM RATINGS (measured vs. GND pin 3, unless otherwise noted) Rating Main Supply Voltage Input Voltage between PGND and AGND PWM Feedback Voltage Error Amplifier Voltage Enable Voltage PG Voltage VSW to AGND or PGND VSW to AGND or ...
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ELECTRICAL CHARACTERISTICS (T (Note 7)) Characteristic Input Voltage Range SUPPLY CURRENT Quiescent Supply Current Shutdown Supply Current UNDER VOLTAGE LOCKOUT VIN UVLO Threshold VIN UVLO Threshold MODULATOR Oscillator Frequency Maximum Duty Ratio Minimum Duty Ratio VIN Soft Start Ramp Time ...
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TYPICAL PERFORMANCE CHARACTERISTICS (Circuit from Figure 25°C, V Figure 3. Light Load (DCM) Operation 1 ms/DIV Figure 5. Start−Up into Full Load 1 ms/DIV Figure 7. 50% to 100% Load Transient 100 ms/DIV = ...
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TYPICAL PERFORMANCE CHARACTERISTICS (Circuit from Figure 25° Input Voltage = Input Voltage = Input Voltage = 4 −50 −30 −10 ...
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TYPICAL PERFORMANCE CHARACTERISTICS (Circuit from Figure 25°C, V 130 120 110 Input Voltage = 4.5 V 100 90 Input Voltage = −50 −30 − TEMPERATURE (°C) Figure ...
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NCP3170A Efficiency and Thermal Derating 100 OUTPUT CURRENT (A) Figure 20. Efficiency (V ...
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NCP3170B Efficiency and Thermal Derating 100 OUTPUT CURRENT (A) Figure 24 ...
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The NCP3170 is a current−mode, step down regulator with an integrated high−side PMOS switch and a low−side NMOS switch. It operates from a 4 input voltage range and supplies load current. ...
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The part can be enabled with standard TTL or high voltage logic by using the configuration below. 4.5 V − VIN LOG EN C1 LOG R2 LOG AGND Figure 32. Logic Turn−on The enable can ...
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V 0.8 V 0.726 FB Voltage Softstart Complete Power Good Figure 36. OOV and OUV Diagram If the power good function is not used, it can be connected to the VSW node to reduce thermal resistance. Do not connect ...
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... When starting the design of a buck regulator important to collect as much information as possible about the behavior of the input and output before starting the design. ON Semiconductor has a Microsoft Excel® based design tool available online under the design tools section of the NCP3170 product page. The tool allows you to capture your design point and optimize the performance of your regulator based on your design criteria ...
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The buck converter produces input voltage (V that are LC filtered to produce a lower DC output voltage (V ). The output voltage can be changed by modifying OUT the on time relative to the switching period (T) or switching ...
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A standard inductor should be found so the inductor will be rounded to 4.7 mH. The inductor should support an RMS current of 3.01 A and a peak current of 3. good design practice is to select an ...
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The main component of the ripple voltage is usually due to the ESR of the output capacitor and the capacitance selected, which can be calculated as shown in Equation 14 ESR_C OUT ESR 8 ...
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Loss in the input capacitors can be calculated with the following equation CIN Iin CIN ESR RMS 1.34 A CIN = Input capacitance Equivalent Series ESR Resistance Iin = ...
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FALL HSPD IG2 = Output current from the low−side gate drive Q = MOSFET gate to drain gate charge MOSFET gate resistance ...
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VIN V L out out (V) (V) (mF) 12 0.8 1.8 12 1.0 2.5 12 1.1 2.5 12 1.2 2.5 12 1.5 3.6 12 1.8 3.6 12 2.5 4.7 12 3.3 4.7 12 5.0 7.2 12 10.68 7.2 NCP3170A 18 ...
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To compensate the converter we must first calculate the current feedback 1. 1.83 500 kHz W 1.358 ...
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Figure 45 shows a pseudo Type III transconductance error amplifier. ZIN IEA ZFB VREF Figure 45. Pseudo Type III Transconductance Error Amplifier The compensation network consists of the internal error amplifier and the impedance networks Z ...
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Transconductance of amplifier y = Amplitude ratio ³ 14. 3. Compensation capacitance Output capacitance OUT F = Current mode ...
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Output Voltage Output Current tss Figure 49. Resistive Load Current Alternatively, if the output load has an under voltage lockout, turns defined voltage level, and draws a constant current, then the RMS connected load current is: V ...
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Figure 52. Recommended Signal Layout The NCP3170 is the major source of power dissipation in the system for which the equations above detailed the loss mechanisms. The control portion of the IC power dissipation is determined by the formula below: ...
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... *For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. Blu−ray and Blu−ray Disc are trademarks of Blu−ray Disc Association. Microsoft Excel is a registered trademark of Microsoft Corporation. ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC) ...