ML4818CS Micro Linear, ML4818CS Datasheet
ML4818CS
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ML4818CS Summary of contents
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Phase Modulation/Soft Switching Controller GENERAL DESCRIPTION The ML4818 is a complete phase modulation control IC suitable for full bridge soft switching converters. Unlike conventional PWM circuits, the phase modulation technique allows for zero-voltage switching transitions and square wave drive across ...
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ML4818 PIN CONNECTION 24-Pin Power DIP GND GND T RAMP OUT OUT LIM E/A OUT GND 6 19 GND GND 7 18 GND INV ...
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ABSOLUTE MAXIMUM RATINGS Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. V ........................................................................... 30V CC Output Driver Current, Source or ...
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ML4818 ELECTRICAL CHARACTERISTICS PARAMETER ERROR AMPLIFIER (Continued) Output Sink Current Output Source Current Output High Voltage Output Low Voltage Unity Gain Bandwidth Slew Rate PHASE MODULATOR RAMP Bias Current EA OUT Zero DC Threshold t , RAMP to Output PD ...
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FUNCTIONAL DESCRIPTION PHASE MODULATOR Power is controlled by modulating the switching phase on sides A and B of the full H-bridge converter (Figure 1). Power is delivered to the output through the transformer secondary. The power conversion process is described ...
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ML4818 The ML4818 can also be used in current mode by sensing load current on the RAMP input (pin 3). The four output delay timers are programmed via an external R resistor as shown below. This resistor DELAY value should ...
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GAIN 100 1k 10k 100k FREQUENCY Figure 6. Error Amplifier Open-Loop Gain and Phase vs. Frequency SOURCE 2 SINK 0.2 0.4 0.6 0.8 OUTPUT ...
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ML4818 CURRENT LIMIT, FAULT DETECTION AND SOFT START Current limit is implemented when the current sensed on I reaches the 1V limit. At this point, the PWM cycle is LIM terminated. The flip flop (Figure 10) turns on the current ...
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UNDER-VOLTAGE LOCKOUT On power up, when V is below 16V, the IC draws very CC little current (1.1mA typ.) and V is disabled. When V REF rises above 16V, the IC becomes active and V enabled and will stay in ...
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ML4818 10 IN5248 x 2 10T 1N5818 IN5248 x 2 1N5818 220pF Figure 16. Offline Full Bridge Converter. 1N5818 ...
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PHYSICAL DIMENSIONS 24 PIN 0.070 MIN (1.77 MIN) (4 PLACES) 0.170 MAX (4.32 MAX) 0.125 MIN (3.18 MIN) inches (millimeters) Package: P24N 24-Pin Narrow PDIP 1.240 - 1.260 (31.49 - 32.01) 0.050 - 0.065 0.100 BSC (1.27 ...
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... ORDERING INFORMATION PART NUMBER ML4818CP ML4818CS © Micro Linear 1997 is a registered trademark of Micro Linear Corporation Micro Linear Products described in this document may be covered by one or more of the following patents, U.S.: 4,897,611; 4,964,026; 5,027,116; 5,281,862; 5,283,483; 5,418,502; 5,508,570; 5,510,727; 5,523,940; 5,546,017; 5,559,470; 5,565,761; 5,592,128; 5,594,376; Japan: 2598946; 2619299. Other patents are pending. ...