LT1242 LINER [Linear Technology], LT1242 Datasheet
LT1242
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LT1242 Summary of contents
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FEATURE S Low Start-Up Current: < 250 A 50ns Current Sense Delay Current Mode Operation: To 500kHz Pin Compatible with UC1842 Series Undervoltage Lockout with Hysteresis No Cross-Conduction Current Trimmed Bandgap Reference 1A Totem Pole Output Trimmed Oscillator Frequency and ...
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LT1241 Series BSOLUTE Supply Voltage ........................................................ 25V Output Current ....................................................... 1A* Output Energy (Capacitive Load per Cycle) ...............5 J Analog Inputs (Pins 2, 3) ............................... – 0 Error Amplifier Output Sink ...
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... Minimum Operating Voltage LT1241/LT1243/LT1245 LT1242/LT1244 Hysteresis LT1241 LT1242/LT1244 LT1243/LT1245 PWM Maximum Duty Cycle LT1241/LT1244/LT1245 T LT1242/LT1243 T Minimum Duty Cycle Total Device Start-Up Current Operating Current The denotes those specifications which apply over the full operating temperature range. Note 1: Unless otherwise specified 15V, R ...
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... 10k 15pF 10k 100k 1M OSCILLATOR FREQUENCY (Hz) LT1241 • TPC18 HARA TERISTICS C Undervoltage Lockout – LT1242, LT1244 17 START-UP THRESHOLD MINIMUM OPERATING VOLTAGE 10 9 –50 – TEMPERATURE ( C) LT1241 • TPC02 Start-Up Current 200 180 160 140 ...
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W U TYPICAL PERFOR A Reference Voltage 5. 1mA O 5.04 5.03 5.02 5.01 5.00 4.99 4.98 4.97 4.96 4.95 –50 – 100 125 TEMPERATURE ( C) LT1241 • TPC10 Error Amplifier Open-Loop Gain ...
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... LT1241 Series W U TYPICAL PERFOR A Output Deadtime vs Oscillator Frequency – LT1242, LT1244 60 50 5nF 2nF 1nF 40 30 500pF 20 10 100pF 0 0 100 1000 OSCILLATOR FREQUENCY (kHz) LT1241 • TPC19 Output Rise and Fall Time TIME 50ns/DIV V = 15V LT1241 • TPC22 1nF ...
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... U PPLICATI S I FOR ATIO A MINIMUM START-UP OPERATING MAXIMUM DEVICE THRESHOLD VOLTAGE LT1241 9.6V 7.6V LT1242 16V 10V LT1243 8.4V 7.6V LT1244 16V 10V LT1245 8.4V 7.6V Oscillator The LT1241 series devices are fixed frequency current mode pulse width modulators. The oscillator frequency and the oscillator discharge current are both trimmed and tightly specified to minimize the variations in frequency and deadtime ...
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... The output switching frequency will be equal to the oscillator frequency for LT1242 and LT1243. The output switching frequency will be equal to one-half the oscillator 8 W ...
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PPLICATI S I FOR ATIO Current Sense Comparator and PWM Latch LT1241 series devices are current mode controllers. Under normal operating conditions the output (Pin 6) is turned on at the start of every oscillator cycle, ...
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LT1241 Series PPLICATI S I FOR ATIO Undervoltage Lockout The LT1241 series devices incorporate an undervoltage lockout comparator which prevents the internal reference circuitry and the output from starting up until the supply voltage reaches the ...
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O U TYPICAL A PPLICATI External Clock Synchronization V REF 8 5V REF OSCILLATOR EXTERNAL C SYNC T 0.01 F INPUT + REQUIRED IF THE SYNC AMPLITUDE IS LARGE ...
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LT1241 Series U O TYPICAL A PPLICATI HOT 90VAC R5 0 250V BALEN 240VAC 1/2W MP3- NEU 1212-R6103 COILTRONICS AC GND R T1 MCID404 2KBPOO5M + C14 100 F 400V D6 ...
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O U TYPICAL A PPLICATI V REF COMP – 2.5V PACKAGE DESCRIPTIO CORNER LEADS OPTION (4 PLCS) 0.045 – 0.068 (1.143 – 1.727) FULL LEAD OPTION ...
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LT1241 Series PACKAGE DESCRIPTIO 0.300 – 0.325 (7.620 – 8.255) 0.009 – 0.015 (0.229 – 0.381) +0.025 0.325 –0.015 +0.635 8.255 –0.381 *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH ...
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PACKAGE DESCRIPTIO 0.010 – 0.020 45 (0.254 – 0.508) 0.008 – 0.010 (0.203 – 0.254) 0.016 – 0.050 0.406 – 1.270 * DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSION DOES ...
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LT1241 Series U TYPICAL APPLICATION V REF OUT T COMP 1 R SLOPE R f – 2.5V RELATED PARTS PART NUMBER DESCRIPTION LT1246 1MHz Current ...