ncp1608 ON Semiconductor, ncp1608 Datasheet
ncp1608
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ncp1608 Summary of contents
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... W). It uses critical conduction mode (CrM) to ensure near unity power factor across a wide range of input voltages and output power. The NCP1608 minimizes the number of external components by integrating safety features, making it an excellent choice for designing robust PFC stages available in a SOIC− ...
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... COMP ZCD V I charge LEB R sense + ZCD R ZCD ZCD Clamp ZCD R NCP1608 out1 Control out2 COMP t Figure 1. Typical Application OVP + − OVP UVP POK − + UVP (Enable EA) − ...
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Table 1. PIN FUNCTION DESCRIPTION Pin Name 1 FB The FB pin is the inverting input of the internal error amplifier. A resistor divider scales the output voltage to V tain regulation. The feedback voltage is used for overvoltage and ...
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Table 3. ELECTRICAL CHARACTERISTICS Control CS (For typical values 25°C. For min/max values Characteristic STARTUP AND SUPPLY CIRCUITS ...
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Table 3. ELECTRICAL CHARACTERISTICS Control CS (For typical values 25°C. For min/max values Characteristic RAMP CONTROL Ct Peak ...
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T , JUNCTION TEMPERATURE (°C) J Figure 3. Overvoltage Detect Threshold vs. Junction Temperature 0.330 0.325 0.320 0.315 0.310 0.305 0.300 −50 − JUNCTION TEMPERATURE ...
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T , JUNCTION TEMPERATURE (°C) J Figure 9. Error Amplifier Sink Current vs. Junction Temperature 125 120 115 110 105 100 −50 − ...
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T , JUNCTION TEMPERATURE (°C) J Figure 15. Ct Peak Voltage vs. Junction Temperature 0.520 0.515 0.510 0.505 0.500 0.495 0.490 0.485 0.480 −50 − ...
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V 12 CC(on CC(off −50 − JUNCTION TEMPERATURE (°C) J Figure 21. Supply Voltage Thresholds vs. Junction Temperature 2.16 2.14 2.12 2.10 2.08 2.06 2.04 2.02 2.00 −50 ...
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... Introduction The NCP1608 is a voltage mode, power factor correction (PFC) controller designed to drive cost−effective pre-converters to comply with line current harmonic regulations. This controller operates in critical conduction mode (CrM) suitable for applications up to 350 W. Its voltage mode scheme enables it to obtain near unity power factor without the need for a line-sensing network ...
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... AC Line + Frequency Bypass Capacitor Figure 26. Active PFC Pre−Converter with the NCP1608 The boost (or step up) converter is the most popular topology for active power factor correction. With the proper control, it produces a constant voltage while consuming a sinusoidal current from the line. For medium power (< ...
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... MOSFET (eq. 1) Figure 28. Inductor Waveform During CrM Operation Error Amplifier Regulation The NCP1608 regulates the boost output voltage using an internal error amplifier (EA). The negative terminal of the EA is pinned out to FB, the positive terminal is connected to a 2.5 V ± 1.6% reference (V output is pinned out to Control (Figure 29). ...
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... The switching pattern consists of constant on times and Control variable off times for a given rms input voltage and output load. The NCP1608 controls the on time with the capacitor connected to the Ct pin. A current source charges the Ct capacitor to a voltage derived from the Control pin voltage (V ) ...
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... When the inductor current reaches zero, the ZCD pin voltage (V drain (V ZCD(WIND) volts. The NCP1608 detects the falling edge of V turns the driver on. To ensure that a ZCD event is not inadvertently detected, the NCP1608 logic verifies that V exceeds V ZCD decreases to less than V http://onsemi ...
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... Where Vac is the maximum rms input voltage and 1.55 V (maximum value). ZCD(ARM) The NCP1608 prevents excessive voltages on the ZCD pin by clamping V . When the ZCD winding is negative, ZCD the ZCD pin is internally clamped to V when the ZCD winding is positive, the ZCD pin is internally clamped to V ...
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During the delay caused by R and the ZCD pin capacitance, the equivalent drain capacitance (C ZCD through the path shown in Figure 35 EMI AC Line Filter Figure 35. Equivalent Drain Capacitance Discharge Path C is the ...
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... When V exceeds V CC logic of the NCP1608 are enabled. The controller includes an undervoltage lockout (UVLO) feature that ensures that the NCP1608 is enabled until This hysteresis ensures sufficient time for the ...
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... PFC(Vcc NCP1608 Figure 40. NCP1608 Supplied by a Downstream SMPS Controller (NCP1230) Soft Start When V exceeds begins counting. When CC CC(on) start t expires, the error amplifier is enabled and begins start charging the compensation network. The drive is enabled when V exceeds Ct . The charging of the ...
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... V ripple(peak-peak) V ripple(peak−peak) The OVP logic includes hysteresis (V (eq. 13) ensure that out2 FB NCP1608 attempts to restart and to ensure noise immunity The output voltage at which the NCP1608 attempts a restart out2 FB (V out(OVPL) V OVP @ REF OVP(HYS) V REF V out Figure 43 ...
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... Control V EAH Clamp Figure 44. Open Feedback Loop Protection Shutdown Mode The NCP1608 enables the user to set the controller in a standby mode of operation. To shutdown the controller, the . The maximum FB pin is forced to less than V . for shutdown (Figure 46), the designer must ensure that no sense significant leakage current exists in the shutdown circuitry ...
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... Application Information ON Semiconductor provides an electronic design tool, a demonstration board, and an application note to facilitate the design of the NCP1608 and reduce development cycle time. All the tools can be downloaded or ordered at www.onsemi.com. Bridge The electronic design tool allows the user to easily determine most of the system parameters of a boost pre− ...
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BOOST DESIGN EQUATIONS Components are identified in Figure 1 Input rms Current Inductor Peak Current Inductor Value On Time Off Time Switching Frequency Time Capacitor Inductor Turns to ZCD Turns Ratio Resistor from ZCD Winding to the ...
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BOOST DESIGN EQUATIONS Components are identified in Figure 1 (Continued) Output Voltage UVP Detection V out(UVP) Inductor rms Current Output Diode rms Current I MOSFET rms Current + 2 I M(RMS) Current Sense Resistor Type 1 Compensation ...
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... Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. The products described herein (NCP1608), may be covered by one or more of the following U.S. patents: 6,362,067, 5,359,281, 5,073,850. There may be other patents pending. ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC) ...