LT1509 Linear Technology, LT1509 Datasheet
LT1509
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LT1509 Summary of contents
Page 1
... 200 – 4 – C SET + CL 1V – + 1.2V – – RAMP V C LT1509 Power Factor and PWM Controller U GND1 – + – RUN + S 0.7V OSC 16V 15 R SET 55% DELAY 200ns 16V BLANKING V LIM CC 17 ...
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... Line current dead zone is minimized with low bias voltage at the current input to the multiplier. The LT1509 provides many protection features including peak current limiting and overvoltage protection. Imple- mented with a very high speed process, the LT1509 can be operated at frequencies as high as 300kHz. U RATINGS ...
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... SET SET OVP = 7.5V 0mA Load, 18V < – 200mA Load, 11.5V V 15V 0V, 50mA Load (Sinking) CC 200mA Load (Sinking) 10mA Load 10nF from GTDR to GND 1nF from GTDR to GND LT1509 = 100 0V 3.5V, AC SENSE OUT MIN TYP MAX UNITS – 25 – 250 ...
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... Current Limit Comparator (CL) Threshold GTDR2 Switching Off Threshold SS2 C V Input Current C PWMOK Comparator Low Threshold (in Terms Pin High Voltage (LT1509) C GTDR2 Turn-On Blanking Time The denotes specifications which apply over the full operating temperature range. I Note 1: Multiplier Gain Constant ...
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... VA = 6.5V OUT OUT OUT VA OUT VA OUT VA OUT VA OUT VA 0 OUT 0 250 500 LT1509 • TPC05 Start-Up Supply Current vs Supply Voltage 550 500 450 400 350 300 250 200 150 100 SUPPLY VOLTAGE (V) M Pin Characteristics OUT 1 ...
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... V REF circuitry and can source up to 5mA externally. V (Pin 14): This is the inverting input to the voltage SENSE amplifier. PK Pin Characteristics LIM T = 125 – –0.8 –0.4 0 0.4 0.8 PK VOLTAGE (V) LIM LT1509 • TPC13 biases most of the internal REF goes CC ...
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... During this ramp up, PFC reference voltage is equal to SS1 voltage. After SS1 rises past 7.5V, reference voltage remains at 7.5V. V (Pin 17): This is the supply for the chip. The LT1509 CC has two fast gate drivers required to fast charge high power MOSFET gate capacitances. Good supply bypass- ing is required consisting ...
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... error amplifier output voltage required at the input to the multiplier is: (V )(L)(f ) OSC SW (V )(R ) OUT S = 4.4 (V )(R ) OUT S = (j)(2 f)(L)(V ) OSC 3648 = (j)( –15 –30 100 1k 10k 100k 1M FREQUENCY (Hz) LT1509 • F04 Figure )/(200 A ) with I = (VA – 2V)/ 25k. The EA OUT ...
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... Note that of (I OUT. M(MAX) = 15k. a 100kHz switching frequency with R (100kHz)(15k) = 1nF. For added protection the LT1509 provides a second independent current limit comparator. When the input voltage to the comparator ( 5.5V OUT below 0V, GTDR1 pin quickly goes low turning off the PFC power switch ...
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... Because of the slow loop response necessary for power factor correction, output overshoot can occur following a sudden load reduction or removal. To protect downstream components, the LT1509 provides an overvoltage com- parator which senses the output voltage and quickly reduces the line current demand. Referring back to Figure ...
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... SS2 low disabling the PWM section if the PFC output voltage falls below approximately 62% of its preset value (240V with nominal 382V output). Start Up and Supply Voltage The LT1509 draws only 250 A before the chip starts at 16V trickle start, a 91k resistor from the power CC ...
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... For longer life a capacitor with a higher ripple current rating or parallel capacitors should be used. PWM Comparators The LT1509 includes two comparators in the PWM section which implement peak current mode control. The primary current sense voltage is fed into the RAMP pin. The V Control Voltage pin sets the primary peak current level. An ...
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... U U APPLICATIONS INFORMATION W U LT1509 13 ...
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... Controlling the output current during an output short circuit depends on the duty cycle reducing to a small fraction of steady state. An additional transistor disables blanking during turn-on and output short circuit. 5A/DIV 0.5V/DIV Figure 10 90 200W/300W 85 100W 80 75 30W 70 90 132 180 V RMS LT1509 • F11 Figure 11 250 ...
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... TYP 0.018 0.003 (0.457 0.076) N20 0695 0.496 – 0.512* (12.598 – 13.005 0.394 – 0.419 (10.007 – 10.643 0.037 – 0.045 (0.940 – 1.143) 0.004 – 0.012 (0.102 – 0.305) SOL20 0695 LT1509 15 ...
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... LT1509 RELATED PARTS PART NUMBER DESCRIPTION LT1084 5A Low Dropout Linear Regulator LT1105 Simplified Off-Line Controller LT1241-5 High Frequency Current Mode PWM Controller LT1247 High Frequency Current Mode PWM Controller LT1248 Full-Feature Average Current Mode Power Factor Controller LT1249 Minimal Parts Count Power Factor Controller ...