lt1303-5 Linear Technology Corporation, lt1303-5 Datasheet
lt1303-5
Related parts for lt1303-5
lt1303-5 Summary of contents
Page 1
... The on-chip NPN power switch has a low 170mV saturation voltage at a switch current of 1A. The LT1303/LT1303-5 are available in 8-lead PDIP or SO packages, easing board space requirements. For higher output current, please see the LT1305 or LT1302 ...
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... ABSOLUTE MAXIMUM V Voltage .............................................................. 10V IN SW1 Voltage ............................................................ 25V Sense Voltage (LT1303-5) ....................................... 20V FB Voltage (LT1303) ................................................ 10V Shutdown Voltage ................................................... 10V LBO Voltage ............................................................. 10V LBI Voltage .............................................................. 10V Maximum Power Dissipation ............................. 500mW Operating Temperature Range ..................... Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C ...
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... FB Pin Bias Current 100 –50 – TEMPERATURE ( C) LT1303/LT1303-5 LT1303-5 Sense Pin Resistance to Ground 1000 900 800 700 600 500 400 300 –50 25 – 100 TEMPERATURE (˚C) LT1303 G02 Low Battery Detect Trip Point 1.250 1 ...
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... LT1303/LT1303 TYPICAL PERFORMANCE CHARACTERISTICS Switch On-Time – –25 TEMPERATURE ( C) LT1303 G10 Quiescent Current 200 SWITCH OFF 190 180 170 160 150 140 130 120 110 100 –50 – TEMPERATURE ( C) LT1303 G13 Transient Response ...
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... Can sink 100 A. Disabled when device is in shutdown. SHDN (Pin 3): Shutdown. Pull high to shut down the device. Ground for normal operation. FB/Sense (Pin 4): On 1303 (adjustable) this pin connects to the main comparator C1 input. On LT1303-5 this pin connects to the resistor string that sets output voltage at 5V. W BLOCK ...
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... A3 OSCILLATOR C1 DRIVER + – LBI LBO 5 2 Figure 3. LT1303-5 Block Diagram output capacitor large. The 100 F unit specified results in ripple of 50mV to 100mV on the 5V output. A 220 F capacitor will decrease ripple by approximately 50%. V OUT 100mV/DIV AC COUPLED V SW 5V/DIV I 1A/DIV Figure 4. Burst Mode Operation in Action If switch current reaches 1A, causing C2 to trip, switch on- time is reduced and off-time increases slightly ...
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... Figure 9’s inductor has high DC resistance which results in the exponential time constant shape of the inductor current. 500mA/DIV PHONE (708) 639-6400 (407) 241-7876 Figure 7. Properly Chosen Inductor Does Not Saturate (708) 956-0666 (716) 532-2234 LT1303/LT1303 100k V IN LBO 2N3906 LT1303 R2 ...
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... LT1303/LT1303 APPLICATIONS INFORMATION Figure 8. This Inductor Saturates at I Figure 9. Slight Exponential Shape to Inductor Current Waveform Indicates Excessive DC Resistance Diode Selection The LT1303’s high switching speed demands a high speed rectifier. Schottky diodes are preferred for their low for- ward drop and fast recovery. Suitable choices include the 1N5817, MBRS120LT3, and MBR0520LT1 ...
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... LT1303 100 F FB GND PGND R1 = 1.24V OUT R1 5V Step-Up Converter with Reference Output 22 H* 100k V IN LBO 2N3906 + LT1303-5 100 F LBI GND 2.2 F 33k LT1303/LT1303-5 V OUT + 100 F 1303 TA03 1N5817 SW OUTPUT SENSE 5V + 100 F SHDN PGND 1303 TA04 9 ...
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... F * SUMIDA CD54-100MC ** AVX TPS 330 F/6.3V † 1% METAL FILM 10 4-, 5-Cell to 5V Converter with Output Disconnect 510 MBRS130T3 SENSE + LT1303 SHDN GND PGND SHUTDOWN * SUMIDA CD54-100MC ** AVX TPS 220 F/10V MBRS130T3 10 H* 100k SHDN LB0 LT1303 ...
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... EL Panel Driver T1** MUR160 1:15 • 4,5 6 • 1,2 1N5818 3. 3.3M IN 0.1 F 3.3M LT1303 CERAMIC 1N4148 FB SHDN GND PGND 51k SHUTDOWN † R1 25k TO 115V RMS RMS LT1303/LT1303-5 C1* 50pF 4.7 F 160V + 1k EL PANEL 1/2W 10k MPSA42 LT1303 TA06 11 ...
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... LT1303/LT1303-5 PACKAGE DESCRIPTION 0.300 – 0.325 (7.620 – 8.255) 0.065 (1.651) 0.009 – 0.015 TYP (0.229 – 0.381) 0.005 (0.127) +0.025 0.325 MIN –0.015 +0.635 8.255 –0.381 0.100 0.010 (2.540 0.254) *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm) 0.010 – ...