NCP1606 ON Semiconductor, NCP1606 Datasheet

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... NCP1606 Cost Effective Power Factor Controller The NCP1606 is an active power factor controller specifically designed for use as a pre−converter in electronic ballasts, ac−dc adapters and other medium power off line converters (typically up to 300 W). It embeds a Critical Conduction Mode (CRM) scheme that substantially exhibits unity power factor across a wide range of input voltages and power levels. Housed in a DIP8 or SOIC− ...

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Shutdown V OUT nPOK + R C OUT1 BULK FB E/A ESD R OUT2 D BOOST + 2 COMP V CONTROL Control ESD BOOST 270 mA Ct ESD Ct CS ESD R SENSE V DD ...

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PIN FUNCTION DESCRIPTION Pin Number Name 1 Feedback (FB) The FB pin makes available the inverting input of the internal error amplifier. A simple resistor divider scales and delivers the output voltage to the FB pin to maintain regulation. The ...

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... V (diff) V (diff − Difference between max and min Control voltages CURRENT SENSE BLOCK V Overcurrent Protection Threshold: CS(limit) NCP1606A NCP1606B t Leading Edge Blanking duration LEB t Overcurrent protection propagation delay bias current @ ZERO CURRENT DETECTION V H Zero Current Detection Threshold (V ...

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... Maximum Ct level before DRV switches off CTMAX t Propagation delay of the PWM comparator PWM OVER AND UNDERVOLTAGE PROTECTION I Dynamic overvoltage protection (OVP) triggering current: OVP NCP1606A NCP1606B @ T = 25°C J NCP1606B @ T = −25°C to +125° Hysteresis of the dynamic OVP current before the OVP latch is released: OVP(HYS) NCP1606A ...

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TEMPERATURE (°C) Figure 3. Oscillator Charge Current (I vs. Temperature 3.30 3.25 3.20 3.15 3.10 3.05 3.00 −50 − TEMPERATURE (°C) Figure ...

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I 40 OVP OVP(HYS −50 − TEMPERATURE (°C) Figure 9. Overvoltage Activation Current vs. Temperature for the A Version 2.20 2.15 2.10 2.05 2.00 1.95 1.90 −50 − ...

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−50 − TEMPERATURE (°C) Figure 15. Output Gate Drive Resistance (R and 100 mA vs. Temperature OL 1.710 1.705 1.700 1.695 ...

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... The output voltage is accurately controlled by a high precision error amplifier. The controller also implements a comprehensive array of safety features for robust designs. The key features of the NCP1606 are as follows: • Constant on time (Voltage Mode) CRM operation. High power factor ratios are easily obtained without the need for input voltage sensing ...

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... AC Line + Frequency Bypass Capacitor Figure 22. Active PFC Pre−Converter with the NCP1606 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 drawing a sinusoidal current from the line. For medium power (< ...

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... Figure 24. Inductor Waveform During CRM Operation ERROR AMPLIFIER REGULATION ) to The NCP1606 is configured to regulate the boost output LPK voltage based on its built in error amplifier (EA). The error amplifier ’s negative terminal is pinned out to FB, the positive terminal is tied to a 2.5 V ± 1.5% reference, and the output is pinned out to Control (Figure 25) ...

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... R line where G is the attenuation level in dB (commonly 60 dB) ON TIME SEQUENCE Since the NCP1606 is designed to control a CRM boost converter, its switching pattern must accommodate constant on times and variable off times. The Controller generates the on time via an external capacitor connected to pin 3 (Ct). A current source charges this capacitor to a level determined by the Control pin voltage ...

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... When the inductor current drops to zero, then the ZCD voltage falls and starts to ring around zero volts. The NCP1606 detects this falling edge and starts the next driver on time. To ensure that a ZCD event has truly occurred, the NCP1606’s logic (Figure 29) waits for ...

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... V capacitor to the (12 V typical). Because of the very low consumption of the NCP1606 during this stage (< 40 mA), most of the current goes directly to charging up the V provides faster startup times and reduced standby power dissipation. When the V voltage exceeds the V CC ...

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... The NCP1606 detects these excessive V OUTPUT DRIVER The NCP1606 includes a powerful output driver capable of peak currents of +500 mA and −800 mA. This enables the controller to efficiently drive power MOSFETs for medium power (up to 300 W) applications. Additionally, the driver stage is equipped with both passive and active pull down clamps (Figure 33) ...

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... The circuit senses this current and disables the drive (pin 7) when , COMP I CONTROL + 2 NCP1606B). This gives the OVP threshold as: (eq OUT2 (V By simply adjusting R set. Therefore, one can compute the R resistances using the following procedure: 1 ...

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... Vac. Overcurrent Protection (OCP) A dedicated pin on the NCP1606 senses the peak current and limits the driver on time if this current exceeds V . This level is 1.7 V (typ) on the NCP1606A and CS(limit) 0.5 V (typ) on the NCP1606B. Therefore, the maximum peak current can be adjusted by changing R I peak An internal LEB filter (Figure 20) reduces the likelihood of switching noise falsely triggering the OCP limit ...

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... Shutdown Figure 39. Shutdown Comparator and Current Draw to Overcome Negative Clamp SHUTDOWN MODE The NCP1606 allows for two methods to place the controller into a standby mode of operation. The FB pin can be pulled below the UVP level (0.3 V typical) or the ZCD pin can be pulled below the V ...

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... NCP1606 specifi- OVP cation table lower for the OVP NCP1606B, then for the NCP1606A version given in the NCP1606 speci- UVP fication table. Use for worst case at LINE universal lines. The ripple must not exceed the OVP level for V ...

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... I (typ) (Note 4) OVP and OVP http://onsemi.com given in the NCP1606 CS(limit) specification table. The NCP1606B has a lower V level. CS(limit the desired attenuation in deci- bels (dB). Typically dB. † Package Shipping PDIP−8 50 Units / Rail SOIC− ...

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... C SEATING PLANE −Z− 0.25 (0.010 *For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. PACKAGE DIMENSIONS SOIC−8 NB CASE 751−07 ISSUE 0.10 (0.004) ...

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... G H 0.13 (0.005) The product described herein (NCP1606), may be covered by the following U.S. patents: 5,073,850 and 6,362,067. There may be other patents pending. ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. “ ...