m51996ap Renesas Electronics Corporation., m51996ap Datasheet
m51996ap
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m51996ap Summary of contents
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... M51996AP/AFP Switching Regulator Control Description M51996A 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 pulse and with a large-drive totempole output. ...
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... M51996AP/AFP Recommended Operating Conditions Supply voltage range Operating frequency: less than 500 kHz Oscillator frequency setting resistance T-ON pin resistance T-OFF pin resistance to30 k OFF Block Diagram REG (7.8 V) Voltage regulator Under voltage lockout Latch OVP CF Oscillator ...
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... M51996AP/AFP Pin Arrangement REJ03D0836-0201 Rev.2.01 Nov 14, 2007 Page M51996AP V Collector CLM+ OUT Emitter GND 3 12 OVP T-OFF DET 6 9 T-ON REG SOFT 7 8 (Top view) Outline: PRDP0014AA-A (14P4) M51996AFP V Collector CLM+ OUT Emitter ...
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... M51996AP/AFP Absolute Maximum Ratings Item Supply voltage Collector voltage Output current V terminal output current REG SOFT terminal voltage CLM terminal voltage DET terminal voltage OVP terminal current F/B terminal current T-ON terminal input current T-OFF terminal input current Power dissipation Thermal derating Operating temperature Storage temperature Notes: 1. “ ...
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... M51996AP/AFP Electrical Characteristics Block Item Supply Operating supply voltage/ voltage range circuit Operation start up current voltage Operation stop voltage CC(START) CC(STOP) difference Stand-by current Operating circuit current Circuit current in OVP state F/B Current at 0 duty Current at maximum duty Current difference between max and 0 ...
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... M51996AP/AFP Block Item Oscillator Oscillating frequency Maximum ON duty Upper limit voltage of oscillation waveform Lower limit voltage of oscillation waveform Voltage difference between upper limit and lower limit of OSC waveform T-ON terminal voltage T-OFF terminal voltage SOFT Oscillating V SOFT frequency 5.5 V during V SOFT SOFT 2.5 V operation ...
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... M51996AP/AFP Main Characteristics Thermal Derating (Maximum Rating) 1800 1500 1200 900 600 300 Ambient Temperature Ta (°C) SOFT Terminal Input Voltage vs. Expansion Rate of Period 5.0 ( kΩ 4.0 ( kΩ ( kΩ ( kΩ ( kΩ ...
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... M51996AP/AFP CLM+ Terminal Current vs. CLM+ Terminal Voltage 400 300 200 100 0 0 0.1 0.2 0.3 0.4 0.5 CLM+ Terminal Voltage V Output High Voltage vs. Source Current 4 4 25°C 3.9 3.6 3.3 3.0 2.7 2.4 2.1 1.8 1.5 1.2 −3 −2 − Source Current I Detection Voltage vs. Ambient Temperature 2.55 2.50 2.45 2.40 −60 −40 − Ambient Temperature Ta (°C) REJ03D0836-0201 Rev ...
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... M51996AP/AFP Voltage Gain of Detection AMP vs. Frequency Frequency f (Hz) ON Duty vs. F/B Terminal Input Current 0.4 0.6 0.8 1.0 1.2 F/B Terminal Input Current I Upper & Lower Limit Voltage of OSC vs. Ambient Temperature kΩ kΩ OFF 4 ...
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... M51996AP/AFP ON Duty vs. R 100 OFF Oscillator Frequency vs. Ambient Temperature 700 600 500 400 300 200 −60 −40 − Ambient Temperature Ta (°C) ON Duty vs. Ambient Temperature 100 kΩ kΩ, R ...
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... M51996AP/AFP OVP Terminal Input Current vs. Input Voltage ° ° −30 °C 100 µ 10 µ 1 µ 0.2 0.4 0.6 OVP Terminal Input Voltage V Circuit Current vs. Supply Voltage (OVP Operation) 8.0 OVP reset point 8.87 V (−30 °C) 7.0 8.94 V (25 °C) 9.23 V (85 °C) 6 °C 5 ° − ...
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... M51996AP/AFP Application Example (1) Application Example for Feed Forward Regulator + + AC R2 input C C FIN VCC (2) Application Example for Fly-back Regulator + + AC input C C FIN VCC REJ03D0836-0201 Rev.2.01 Nov 14, 2007 Page Collector CC REG CLM+ Emitter M51996A SOFT OVP F/B T-ON CF T-OFF + R21 ...
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... M51996AP/AFP Function Description Type M51996AP and M51996AFP are especially designed for off-line primary PWM control IC of switching mode power supply to get DC voltage from AC power supply. Using this IC, smart SMPS can be realized with reasonable cost and compact size as the number of external electric parts can be reduced and also parts can be replaced by reasonable one ...
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... M51996AP/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 of external resistor R mainly determined by the product of resistor R Waveform of CF terminal ...
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... M51996AP/AFP T- T-OFF R OFF M51996A Figure 3 Schematic Diagram of Charging and Discharging Control Circuit for OSC Capacitor C 2. Oscillator operation when the SOFT (soft start) circuit is operating. Output transistor is protected from rush current by CLM function at the start time of power on. SOFT terminal is used to improve the rising response of the output voltage of power supply (prevention of overshooting) ...
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... M51996AP/AFP Waveform of CF terminal Waveform of V terminal in Max ON duty condition Figure 5 Oscillator Waveform When the SOFT Circuit is Operating Voltage waveform of CF Terminal Waveform of V terminal in Max ON duty condition Figure 6 Relationship Between Oscillator Waveform and Output Waveform at Start-up Figure 5 shows the relationship between oscillator waveform and output pulse. ...
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... M51996AP/AFP PWM Comparator, PWM Latch and Current Limit Latch Section Figure 7 shows the schematic diagram of PWM comparator and PWM latch section. The on-duration of output waveform coincides with the rising duration of CF terminal waveform, when the no output current flows from F/B terminal. When the F/B terminal has finite impedance and current flows out from F/B terminal, “A” point potential shown in figure 7 depends on this current. So the “ ...
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... M51996AP/AFP 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 cycle. Figure 9 shows the timing relation among them. ...
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... M51996AP/AFP 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 of common ground circuit of primary and secondary in feed forward system. The circuit diagram is quite similar to that of shunt regulator type 431 as shown in figure 11. As well known from figure 11 and figure 12, the output of OP AMP has the current-sink ability, when the DET terminal voltage is higher than 2 ...
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... M51996AP/AFP OVP Circuit (Over Voltage Protection Circuit) Section OVP circuit is basically positive feedback circuit constructed by Q2 shown in figure 13. Q2, Q3 turn on and the circuit operation of IC stops, when the input signal is applied to OVP terminal. (threshold voltage 750 mV) The current value about 150 A when the OVP does not operates but it decreases to about 2 A when OVP operates ...
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... M51996AP/AFP Figure 14 Circuit Current vs. Supply Voltage (OVP Operation) Output Section It is required that the output circuit have the high sink and source abilities for MOS FET drive well known that the “totempole circuit has high sink and source ability. However, it has the demerit of high through current. ...
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... the normal and optimum gate voltage and the CC output voltage ( type M51996AP/AFP is about ( not necessary that the induced voltage is settled higher than the operation start-up voltage V high gate drive voltage causes high gate dissipation, on the other hand, too low gate drive voltage does not make the MOS FET fully on-state or the saturation state ...
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... M51996AP/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 16 Start-up Circuit Diagram When It is Not Necessary to Set The Start and Stop Input Voltage 3 ...
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... M51996AP/AFP 4. Power supply circuit for easy start-up When IC start 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 charging does occur only the duration while the induced winding voltage is higher than the C induced winding voltage is nearly equal to the “ ...
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... M51996AP/AFP OVP Circuit 1. To avoid the miss operation of OVP It is recommended to connect the capacitor between OVP terminal and GND for avoiding the miss operation by the spike noise. The OVP terminal is connected with the sink current source ( 150 when OVP does not operate, for absorbing the leak current of the photo coupler in the application ...
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... M51996AP/AFP 3. OVP setting method using the induced third winding voltage on fly back system For the over voltage protection (OVP), the induced fly back type third winding voltage can be utilized, as the induced third winding voltage depends on the output voltage. Figure 21 shows one of the example circuit diagram. ...
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... M51996AP/AFP Current Limiting Circuit 1. Peripheral circuit of CLM terminal Figure 23 shows the example circuit diagrams around the CLM terminal required to connect the low pass filter, in order to reduce the spike current component, as the main current or drain current contains the spike current especially during the turn-on duration of MOS FET. ...
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... M51996AP/AFP Figure 25 Over Current Limiting Curve on Feed Forward System If the curve becomes vertical because of an excess current, the output voltage is lowered and no feedback current flows from feedback photo-coupler; the PWM comparator operates to enlarge the duty sufficiently, but the signal from the CLM section operates to make the pulse width narrower. ...
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... M51996AP/AFP M51996A F/B Figure 27 Current to Lower Frequency During Over Current To change the knee point of frequency drop, use the circuit in figure 28. SOFT V OUT Figure 28 Method to Control The Knee Point of Frequency Drop To have a normal SOFT start function in the circuit in figure 27, use the circuit in figure 29 recommended to use ...
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... M51996AP/AFP (2) In case of fly back system The DC output voltage of SMPS depends on the V winding is negative and the system is fly back. So the operation of type M51996A will stop when the V becomes lower than “Operation-stop voltage” of M51996A when the DC output voltage of SMPS decreases under specified value at over load condition. ...
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... M51996AP/AFP Output Circuit 1. The output terminal characteristics at the V The output terminal has the current sink ability even though the V voltage or V (It means that the terminal is “Output low state” and please refer characteristics of output low CC(STOP) voltage versus sink current.) This characteristics has the merit not to damage the MOS FET at the stop of operation when the V decreases lower than the voltage of V characteristics to the output terminal, is drawn out rapidly ...
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... M51996AP/AFP As the gate drive current may reach up to several tenths milliamperes at 500 kHz operation, depending on the size of MOS FET, the power dissipation caused by the gate current can not be neglected. In this case, following action will be considered to avoid heat up of type M51996A. (1) To attach the heat sink to type M51996A ...
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... M51996AP/AFP At the start of the operation, there happen output pulse due to F/B terminal current through C1 and C2, as the potential of F/B terminal rises sharply just after the start of the operation. Not to lack the output pulse, is recommended to connect the capacitor C4 as shown by broken line. Please take notice that the current flows through the R1 and R2 are superposed to I connected shown in figure 18 ...
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... M51996AP/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 switching speed of bipolar transistor fast one. In this case, over current can not be detected by detecting resistor in series to bipolar transistor recommended to use the CT (current transformer) ...
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... M51996AP/AFP Package Dimensions JEITA Package Code RENESAS Code P-SOP16-5.3x10.1-1.27 PRSP0016DE Index mark * JEITA Package Code RENESAS Code P-DIP14-6.3x19-2.54 PRDP0014AA SEATING PLANE REJ03D0836-0201 Rev.2.01 Nov 14, 2007 Page Previous Code MASS[Typ.] 16P2N-A 0. Previous Code MASS[Typ ...
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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 ...