mc44608 ON Semiconductor, mc44608 Datasheet
mc44608
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mc44608 Summary of contents
Page 1
... Few External Components Reliable and Flexible SMPS Controller The MC44608 is a high performance voltage mode controller designed for off−line converters. This high voltage circuit that integrates the startup current source and the oscillator capacitor, requires few external components while offering a high flexibility and reliability ...
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... Output Blanking 2 Isense ORDERING INFORMATION Device MC44608P40 MC44608P40G MC44608P75 MC44608P75G MAXIMUM RATINGS Rating Total Power Supply Current Output Supply Voltage with Respect to Ground All Inputs except Vi Line Voltage Absolute Rating Recommended Line Voltage Operating Condition Power Dissipation and Thermal Characteristics Maximum Power Dissipation 85° ...
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... Propagation Delay (Current Sense Input to Output @ V Leading Edge Blanking Duration Leading Edge Blanking Duration Leading Edge Blanking + Propagation Delay Leading Edge Blanking + Propagation Delay oscillator section Normal Operation Frequency MC44608P40 Normal Operation Frequency MC44608P75 Maximum Duty Cycle @ osc OVERvoltage section Quick OVP Input Filtering (R ...
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... I dem−NM MC44608P40 MC44608P75 stup−uvlo1 H uvlo1−uvlo2 = 100 V) and i MC44608P40 MC44608P75 I CC−latch d http://onsemi.com 4 = −25°C to +85°C unless A Min Typ Max dmg−th H − 30 − dmg − 300 − ...
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... Latched off Phase burst duty cycle described in the chapter “Pulsed Duty Cycle Control” on page 8. PWM Latch Switching Phase The MC44608 works in voltage mode. The on−time is controlled by the PWM comparator that compares the PWM Regulation Comparator oscillator sawtooth with the regulation block output (refer to Output the block diagram on page 2) ...
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... OVP is also disabled Oscillator The MC44608 contains a fixed frequency oscillator built around a fixed value capacitor CT successively charged and discharged by two distinct current sources ICH and IDCH. The window comparator senses the CT voltage value and activates the sources when the voltage is reaching the 2 ...
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... Vcont. In this way the SMPS is regulated with a voltage mode control. Overvoltage Protection The MC44608 offers two OVP functions: − a fixed function that detects when V 15.4 V − a programmable function that uses the demag pin. The current flowing into the demag pin is mirrored and compared to the reference current Iovp (120 mA) ...
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Overload In the hiccup mode the 3 distinct phases are described as follows (refer to Figure 7): The SWITCHING PHASE: The SMPS output is low and the regulation block reacts by increasing the ON time (dmax = 80%). ...
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EQUATION 1 Startup Phase Duration stup * UVLO2) Vcc t start– stup where the startup current flowing through V stup C is the V capacitor value Vcc CC EQUATION 2 Switching Phase Duration: C ...
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EQUATION ccS Stup I stup EQUATION stup where ccs stup ...
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Pin6 V Voltage (V) CC Figure 9. Output Switching Speed 85° −25° 25° 0.0 0.5 ...
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C 10.00 9.00 8.00 25° C 7.00 85° C 6.00 5.00 0 100 200 Vi Pin8 Voltage (Vi) Figure 15. High Voltage Current Source The data in Figure 16 corresponds to the waveform in Figure 17. The Figure ...
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The Figure 19 represents a complete power supply using the secondary reconfiguration. The specification is as follows: Input source: 3 Outputs Output power Standby mode R F6 47288900 FI RFI WIDE C1 FILTER MAINS 100 nF C3 D1, D2, D3, ...
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... DZ1 to the 8.0 V low voltage secondary rail. The voltages The Figure 19 shows the SMPS behavior while working in the reconfigured mode. The top curve represents the V voltage (pin 6 of the MC44608). The middle curve represents the 8.0 V rail. The regulation is taking place at 11. the bottom curve the pin 2 voltage is shown. ...
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... 0.13 (0.005) The product described herein (MC44608), may be covered by one or more of the following U.S. patents: 6,208,538 B1; 6,392,906 B2. 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. “ ...