ml4818 Microsemi Corporation, ml4818 Datasheet
ml4818
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ml4818 Summary of contents
Page 1
... The IC modulates the phases of the two sides of the bridge to control output power. The ML4818 can be operated in current mode. The delay times for the outputs are externally programmable to allow the zero-voltage switching transitions to take place. ...
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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 OUT SOFT START OUT SHUTDOWN 10 15 GND CLOCK 12 13 ...
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... 1mA A O 12V < V < 25V CC 1mA < I < 10mA O 10Hz to 10kHz T = 125 C, 1000 hrs REF 1 < V < < V < 25V CC ML4818 ) .............................–5mA DELAY MIN TYP. MAX UNITS 410 450 525 kHz –0.3 %/V 0.2 % 375 525 kHz 4.7 5.5 6 ...
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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 t DELAY R Voltage DELAY SOFT START Charge Current ...
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... Figure 2). The above sequence is then repeated but with the (set Since opposite polarity on all outputs. DELAY +VIN LEAKAGE B TRANSFORMER DELAY t t PD1 DELAY t t DELAY PD1 B A ML4818 SENSE t DELAY t DELAY t PD1 t DELAY , DELAY 5 ...
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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 be no less than 1k . Expressing R k the delay is: ...
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... OUTPUT CURRENT (A) Figure 8. Output Drive Saturation Voltage vs. Output Current. OUTPUT DRIVER STAGE The ML4818 has four high current high speed totem pole output drivers each capable of 1.5A peak output, designed to quickly switch the gates of capacitive loads, such as power MOSFET transistors. Figure 8 illustrates the saturation characteristics of the ouput drive transistors shown in Figure 7 ...
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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 source to charge C and remains on for the duration of RST the clock period ...
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... TEMPERATURE Figure 13. Supply Current vs. Temperature ( C). THERMAL INFORMATION The ML4818 is offered in a Power DIP package. This package features improved thermal conduction through the leadframe. Much of the heat is conducted through the center 4 grounded leads. Thermal dissipation can be improved with this package by using copper area on the board to function as a heat sink ...
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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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... 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 - 1.65) (2.54 BSC) SEATING PLANE 0.016 - 0.022 (0.40 - 0.56) ML4818 0.240 - 0.270 0.295 - 0.325 (6.09 - 6.86) (7.49 - 8.26) 0.015 MIN (0.38 MIN) 0.008 - 0.012 0º - 15º (0.20 - 0.31) 11 ...
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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. ...