ml4823 Fairchild Semiconductor, ml4823 Datasheet
ml4823
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ml4823 Summary of contents
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... High Frequency Power Supply Controller GENERAL DESCRIPTION The ML4823 High Frequency PWM Controller controller optimized for use in Switch Mode Power Supply designs running at frequencies to 1MHz. Propagation delays are minimal through the comparators and logic for reliable high frequency operation while slew rate and bandwidth are maximized on the error amplifier ...
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... PWR GND I REF LIM GND I /S.D. LIM PIN 9 (12 (13) GND 11 (14 (15) PWR GND Return for the high current totem 13 (17 (18) OUT B 15 (19) V for T 16 (20) 5.1V REF ML4823 20-PIN PLCC (Q20 E/A OUT 4 18 OUTPUT CLOCK ...
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... Storage Temperature Range ..................... –65°C to 150°C Lead Temperature (Soldering 10 sec.) .................... 260°C Thermal Resistance ( Plastic DIP ....................................................... 80°C/W Plastic SOIC................................................... 105°C/W Plastic Chip Carrier (PLCC) .............................. 78°C/W OPERATING CONDITIONS Temperature Range ML4823C .................................................. 0°C to 70°C ML4823I ................................................ –40°C to 85°C = 1000pF Operating Temperature Range CONDITIONS T = 25° ...
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... ML4823 ELECTRICAL CHARACTERISTICS PARAMETER ERROR AMPLIFIER (Continued) CMRR PSRR Output Sink Current Output Source Current Output High Voltage Output Low Voltage Unity Gain Bandwidth Slew Rate PWM COMPARATOR RAMP Bias Current Duty Cycle Range E/A OUT Zero DC Threshold Delay to Output SOFT START ...
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... FUNCTIONAL DESCRIPTION OSCILLATOR The ML4823 oscillator charges the external capacitor (C with a current (I ) equal to 3/R SET SET voltage reaches the upper threshold (Ramp Peak), the comparator changes state and the capacitor discharges to the lower threshold (Ramp Valley) through Q1. While the capacitor is discharging, Q2 provides a high pulse. ...
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... OUT 0.2 0.4 0.6 TIME ( s) Figure 5. Unity Gain Slew Rate OUTPUT DRIVER STAGE The ML4823 Output Driver peak output high speed totem pole circuit designed to quickly switch the gates of capacitive loads, such as power MOSFET transistors Figure 7. Simplified Schematic 3 2 SOURCE 1 SINK ...
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... SOFT START AND CURRENT LIMIT The ML4823 employs two current limits. When the voltage at I /SD exceeds the I LIM LIM REF, the outputs are immediately shut off and the cycle is terminated for the remainder of the oscillator period by resetting the RS flip flop. If the output current is rising quickly (usually due to transformer saturation) such that the voltage on pin 9 reaches 1 ...
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... ML4823 PHYSICAL DIMENSIONS 16 PIN 0.02 MIN (0.50 MIN) (4 PLACES) 0.170 MAX (4.32 MAX) 0.125 MIN (3.18 MIN) 0.385 - 0.395 (9.78 - 10.03) 0.350 - 0.356 (8.89 - 9.04) PIN 1 ID 0.042 - 0.048 6 (1.07 - 1.22) 0.050 BSC (1.27 BSC) 0.026 - 0.032 (0.66 - 0.81) 0.013 - 0.021 (0.33 - 0.53) 8 inches (millimeters) Package: P16 16-Pin PDIP 0.740 - 0.760 (18.79 - 19.31) 0.240 - 0.260 (6.09 - 6.61) 0.055 - 0.065 ...
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... ML4823CP ML4823CQ ML4823CS ML4823IQ ML4823IS ML4823MJ DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. ...