M51995AFP#CF0J Renesas Electronics America, M51995AFP#CF0J Datasheet

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To our customers, Old Company Name in Catalogs and Other Documents st On April 1 , 2010, NEC Electronics Corporation merged with Renesas Technology Corporation, and Renesas Electronics Corporation took over all the business of both companies. Therefore, although the ...

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All information included in this document is current as of the date this document is issued. Such information, however, is subject to change without any prior notice. Before purchasing or using any Renesas Electronics products listed herein, please confirm ...

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M51995AP/AFP Switching Regulator Control Description M51995A is the primary switching regulator controller which is especially designed to get the regulated DC voltage from AC power supply. This IC can directly drive the MOS-FET with fast rise and fast fall output ...

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M51995AP/AFP Recommended Operating Conditions • Supply voltage range • Operating frequency: less than 500 kHz • Oscillator frequency setting resistance  T-ON pin resistance kΩ ON  T-OFF pin resistance ...

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M51995AP/AFP Pin Arrangement REJ03D0835-0300 Rev.3.00 Jun 06, 2008 Page M51995AP V Collector CLM+ OUT Emitter CLM− GND 4 13 ON/OFF OVP T-OFF 6 11 DET CF ...

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M51995AP/AFP Absolute Maximum Ratings Item Supply voltage Collector voltage Output current V terminal voltage F ON/OFF terminal voltage CLM−terminal voltage CLM+terminal voltage OVP terminal current DET terminal voltage DET terminal input current F/B terminal voltage T-ON terminal input current T-OFF ...

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M51995AP/AFP Electrical Characteristics Block Item Supply Operating supply voltage range voltage circuit Operation start-up voltage current Operation stop voltage Difference voltage between operation start and stop Stand-by current Operating circuit current Circuit current in OFF state Circuit current in timer ...

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M51995AP/AFP Block Item Timer Timer frequency Timer charge current OFF time/ON time ratio CLM− CLM−terminal threshold voltage CLM−terminal current Delay time from CLM− OUT CLM+ CLM+ terminal threshold voltage CLM+ terminal current Delay time from CLM ...

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M51995AP/AFP Main Characteristics Thermal Derating (Maximum Rating) 1800 1500 1200 900 600 300 Ambient Temperature Ta (°C) Circuit Current vs. Supply Voltage (OVP Operation) 8.0 OVP reset point 8.87 V (−30 °C) 7.0 8.94 V ...

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M51995AP/AFP Threshold Voltage of ON/OFF Terminal vs. Ambient Temperature 3.4 3.2 3.0 ON→OFF 2.8 2.6 2.4 OFF→ON 2.2 2.0 1.8 −60 −40 − Ambient Temperature Ta (°C) Input Current of VF Terminal vs. Input Voltage −10 −9 ...

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M51995AP/AFP VF Threshold Voltage for Timer vs. Ambient Temperature 4.0 3.5 3.0 2.5 2.0 −60 −40 − Ambient Temperature Ta (°C) Threshold Voltage of CLM− Terminal vs. Ambient Temperature −210 −205 −200 −195 −190 −60 −40 −20 0 ...

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M51995AP/AFP Output Low Voltage vs. Output Sink Current 5 25°C 4 100 m Output Sink Current I Input Current of ...

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M51995AP/AFP ON Duty vs. F/B Terminal Input Current 0.5 1.0 F/B Terminal Input Current I Oscillating Frequency vs. CF Terminal Capacity 10000 1000 kΩ kΩ 100 ...

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M51995AP/AFP ON Duty vs. Ambient Temperature 100 kΩ kΩ kΩ kΩ kΩ ...

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M51995AP/AFP Current from OVP Terminal for OVP Reset vs. Supply Voltage 800 ° °C 700 Ta = −30 °C 600 500 400 300 200 100 Supply Voltage V ...

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M51995AP/AFP Application Example (1) Example application circuit diagram of feed forward regulator FIN (2) Example application circuit diagram of fly-back regulator + C FIN ...

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M51995AP/AFP (3) Feed forward types SMPS with multi-output FIN V OUT VF REJ03D0835-0300 Rev.3.00 Jun 06, 2008 Page Collector M51995AP C ON/OFF + ...

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M51995AP/AFP Function Description Type M51995AP and M51995AFP are especially designed for off-line primary PWM control IC of switching mode power supply (SMPS) to get DC voltage from AC power supply. Using this IC, smart SMPS can be realized with reasonable ...

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M51995AP/AFP Oscillator Section The oscillation waveform is the triangle one. The ON-duration of output pulse depends on the rising duration of the triangle waveform and dead-time is decided by the falling duration. The rising duration is determined by the product ...

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M51995AP/AFP T- T-OFF R OFF M51995A Figure 3 Schematic Diagram of Charging and Discharging Control Circuit for OSC Capacitor C 2. Oscillator operation when intermittent action and OSC control circuit operates. When over current signal ...

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M51995AP/AFP As shown in figure 5, the internal circuit kills the first output pulse in the output waveform. The output waveform will appear from the second pulse cycle because the duration of first cycle takes C with that at the ...

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M51995AP/AFP PWM Comparator and PWM Latch Section Figure 7 shows the PWM comparator and latch section. The on-duration of output waveform coincides with the rising duration of CF terminal waveform, when the infinitive resistor is connected between F/B terminal and ...

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M51995AP/AFP Current Limiting Section When the current-limit signal is applied before the crossing instant of “A” pint potential and CF terminal voltage shown in figure 7, this signal makes the output “off” and the off state will continue until next ...

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M51995AP/AFP M51995A V OUT CLM+ GND (a) In case of CLM+ Figure 10 How to Connect Current Limit Circuit Intermittent Action and Oscillation Control Section When the internal current limiting circuit states to operate and also the VF level decreases ...

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M51995AP/AFP Intermittent Action Circuit Section Intermittent action circuit will start to operate when the output signal from the intermittent action and oscillation control circuit are “high” and also VF terminal voltage is lower than V Figure 12 shows the block ...

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M51995AP/AFP Figure Voltage Detector Circuit (DET) Section The DET terminal can be used to control the output voltage which is determined by the winding ratio of fly back transformer in fly-back system or in case ...

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M51995AP/AFP Figure 16 Equivalent Circuit Diagram of Voltage Detector ON-OFF Circuit Section Figure 17 shows the circuit diagram of ON-OFF circuit. The current flown into the ON-OFF terminal makes the Q4 “on” and the switching operation stop. On the other ...

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M51995AP/AFP Figure 18 Connecting of ON/OFF Terminal OVP Circuit (Over Voltage Protection Circuit) Section OVP circuit is basically positive feedback circuit constructed by Q2 shown in figure 20. Q2, Q3 turn on and the circuit operation of IC ...

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M51995AP/AFP As the OVP reset voltage is settled on the rather high voltage of 9.0 V, SMPS can be reset in rather short time from the switch-off of the AC power source if the smoothing capacitor is not so large ...

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M51995AP/AFP Application Note of Type M51995AP/AFP Design of Start-up Circuit and the Power Supply The start-up circuit when it is not necessary to set the start and stop input voltage Rectified DC voltage from smoothing capacitor Figure ...

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M51995AP/AFP When the third winding is the “fly back winding” or “reverse polarity”, the V V can not be settled by this system, so the auxiliary circuit is required. IN(STOP) Rectified DC voltage from smoothing capacitor Figure 23 Start-up Circuit ...

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M51995AP/AFP 4. Power supply circuit for easy start-up When IC starts to operate, the voltage of the C third winding of main-transformer as the I “unstable start-up” or “fall to start-up” may happen, as the charging interval of C the ...

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M51995AP/AFP 2. Application circuit to make the OVP-reset time fast The reset time may becomes problem when the discharge time constant of C circuit condition recommended to discharge the C OVP-reset time fast. Figure 27 Example Circuit Diagram ...

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M51995AP/AFP Current Limiting Circuit 1. Peripheral circuit of CLM+, CLM− terminal + C FIN Input smoothing capacitor Figure 29 Peripheral Circuit Diagram of CLM+ Terminal + C FIN Input smoothing capacitor Figure 30 Peripheral Circuit Diagram of CLM− Terminal Figure ...

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M51995AP/AFP 2. Over current limiting curve (1) In case of feed forward system CLM R I CLM 1 (a) Feed forward system Figure 31 Primary and Secondary Current Waveforms Under the Current Limiting Operation Figure 31 shows the primary and ...

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M51995AP/AFP Figure 33 Feed Back Loop through Low Pass Filter from V Figure 34 shows how to control the knee point where the frequency becomes decrease From V OUT (2) In case of fly back system The DC ...

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M51995AP/AFP However, the M51995A will non-operate and operate intermittently, as the V the decrease of I current. CC The fly back system has the constant output power characteristics as shown in figure 35 when the peak primary current and the ...

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M51995AP/AFP 2. MOS FET gate drive power dissipation Figure 39 shows the relation between the applied gate voltage and the stored gate charge. In the region 1, the charge is mainly stored MOS FET and the high ...

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M51995AP/AFP DET Circuit Figure 41 shows how to use the DET circuit for the voltage detector and error amplifier. M51995A Figure 41 How to use the DET Circuit for the Voltage Detector For the phase shift compensation recommended ...

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M51995AP/AFP How to Get the Narrow Pulse Width During the Start of Operation Figure 43 shows how to get the narrow pulse width during the start of the operation. If the pulse train of forcedly narrowed pulse-width continues too long, ...

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M51995AP/AFP Driver Circuit for Bipolar Transistor When the bipolar transistor is used instead of MOS FET, the base current of bipolar transistor must be sinked by the negative base voltage source for the switching-off duration, in order to make the ...

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M51995AP/AFP Package Dimensions JEITA Package Code RENESAS Code P-SOP20-5.3x12.6-1.27 PRSP0020DA Index mark * JEITA Package Code RENESAS Code P-DIP16-6.3x19-2.54 PRDP0016AA SEATING PLANE REJ03D0835-0300 Rev.3.00 Jun 06, 2008 Page Previous ...

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Notes: 1. This document is provided for reference purposes only so that Renesas customers may select the appropriate Renesas products for their use. Renesas neither makes warranties or representations with respect to the accuracy or completeness of the information contained ...