lx1554 Microsemi Corporation, lx1554 Datasheet
lx1554
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lx1554 Summary of contents
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... LOW COST DC MOTOR CONTROL Part # Start-Up Hysteresis Max. Duty 250µA Voltage LX1552 16V 6V 248K LX1553 8.4V 0.8V 0.56W LX1554 16V 6V LX1555 8.4V 0.8V using the Ceramic DIP TSSOP Y PW 8-pin 20-pin — LX155xCPW — LX155xMY , CA ...
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LX1552/3/4 ...
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(Unless otherwise specified, these specifications apply over the operating ambient temperatures for LX155xC with 0°C ...
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... Gain defined as ISENSE 5. Adjust V above the start threshold before setting at 15V Output frequency equals oscillator frequency for the LX1552 and LX1553. Output frequency is one half oscillator frequency for the LX1554 and LX1555 34V GROUND** 16V (1552/1554) 8.4V (1553/1555) OSCILLATOR ...
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GRAPH / CURVE INDEX Characteristic Curves FIGURE # 1. OSCILLATOR FREQUENCY vs. TIMING RESISTOR 2. ...
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LX1552/3/4/5 FIGURE 1. — OSCILLATOR FREQUENCY vs. TIMING RESISTOR 1000 100 C = 6.8nF T 10 ...
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FIGURE 5. — OUTPUT INITIAL ACCURACY vs. TEMPERATURE 65.0 LX1552 and LX1553 only 63.5 62.0 ...
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... 250 225 200 LX1552/LX1554 175 150 125 100 LX1553/LX1555 -75 -50 - Ambient Temperature - (°C) A 250 LX1552/LX1554 225 T = 25°C A 200 175 150 125 100 Supply Voltage - (V) CC 100 125 ...
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FIGURE 13. — DYNAMIC SUPPLY CURRENT vs. OSCILLATOR FREQUENCY 25° ...
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... FIGURE 20. — LOW LEVEL OUTPUT SATURATION VOLTAGE 1.20 LX1553 1.08 LX1555 0.96 0.84 0.72 0.60 0.48 0.36 0.24 0.12 0. 100 125 -M PWM ODE TEMPERATURE LX1552 LX1554 9.8 9.6 9.4 9.2 9.0 -75 -50 - Ambient Temperature - (°C) A DURING UNDER-VOLTAGE LOCKOUT -55° 25° 125°C A 0.1 1 Output Sink Current - (mA) ...
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FIGURE 21. — OUTPUT SATURATION VOLTAGE vs. OUTPUT CURRENT and TEMPERATURE 6 ...
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... This is especially important in off-line power supplies which are designed to operate for universal input voltages 265V AC. Figure 23 shows an efficient supply voltage using the ultra low start-up current of the LX1554 in conjunction with a bootstrap winding off of the power transformer. Circuit operation is as follows. DC BUS I > ...
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VOLTAGE REFERENCE The voltage reference is a low drift bandgap design which provides +5.0V to ...
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... Example: A flyback power supply design requires the duty cycle to be limited to less than 45%. If the output switching frequency is selected to be 100kHz, what are the values 100 a) LX1552/53, and the b) LX1554/ LX1552/53 Given 100kHz LX1554/55 ...
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... The comparator output resets the PWM latch ensuring that a single pulse appears at the output for any given oscillator cycle. The LX1554/55 series has an additional flip flop stage that limits the output to less than 50% duty cycle range as well as dividing its output frequency to half of the oscillator frequency ...
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LX1552/3/4/5 FIGURE 30. — CURRENT SENSE SPIKE SUPPRESSION LX155x ...
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... This circuit uses a low-cost feedback scheme in which the 60Hz voltage developed from the primary-side control winding is 40KHz ±10% sensed by the LX1554 error amplifier. Load regulation is 25W maximum therefore dependent on the coupling between secondary and 5V +5% control windings, and on transformer leakage inductance. ...