LT1302-5 Linear Technology, LT1302-5 Datasheet
LT1302-5
Related parts for LT1302-5
LT1302-5 Summary of contents
Page 1
... Quiescent current is just 200 A and can be further reduced shutdown. Available in 8-pin PDIP or 8-pin SO packaging, the LT1302/ LT1302-5 have the highest switch current rating of any similarly packaged switching regulators presently on the market. , LTC and LT are registered trademarks of Linear Technology Corporation. ...
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... I Quiescent Current Q V Input Voltage Range IN V Feedback Voltage (LT1302) FB Feedback Pin Bias Current (LT1302) Output Sense Voltage (LT1302-5) Output Ripple Voltage (LT1302-5) Sense Pin Resistance to Ground (LT1302-5) V Offset Voltage OS Comparator Hysteresis Oscillator Frequency DC Maximum Duty Cycle t Switch On Time ON t Switch Off Time ...
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... TEMPERATURE ( C) 1302 G07 Switch Saturation Voltage 600 500 400 300 200 100 5.0 SWITCH CURRENT (A) LT1302-5 Sense Pin Resistance 600 500 400 300 200 100 0 100 –50 – TEMPERATURE ( C) LT1302-5 Output Voltage 5.100 5.075 5.050 5.025 5 ...
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... Frequency Compensation Pin. Connect series GND. Keep trace short. SHDN (Pin 3): Shutdown. Pull high to effect shutdown; tie to ground for normal operation. FB/Sense (Pin 4): Feedback/Sense. On the LT1302 this pin connects to CMP1 input. On the LT1302-5 this pin connects to the output resistor string. 4 Oscillator Frequency 300 275 ...
Page 5
... A2 CMP1 + OFF ENABLE 220kHz OSCILLATOR – HYSTERETIC COMPARATOR 15mV – ERROR AMPLIFIER 22k C4 0.01 F Figure 2. LT1302 Block Diagram LT1302/LT1302 36mV R4 + 1.75 R5 730 – 160X DRIVER BIAS 300 3.6k I PGND OUT + C3 1302 F02 ...
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... ERROR AMPLIFIER Figure 3. LT1302-5 Block Diagram CMP1’s hysteresis (about 5mV) CMP1 turns the oscilla- tor off. In this mode, peak switch current is limited to approximately 1A by A2, Q2, and Q3. Q2’s current, set flows through R5, causing A2’s negative input to be 25mV lower than V 36mV below V The remaining 11mV is generated by Q3’ ...
Page 7
... I ESR when the inductor current is flowing into the SW diode. Figure 4 shows output voltage of an LT1302-5 boost converter with two 220 F AVX TPS capacitors at the output. Ripple voltage at a 510mA load is about 30mV LT1302/LT1302-5 ...
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... LT1302/LT1302 APPLICATIONS INFORMATION and there is no low frequency component. The total ESR is under 0. single 100 F aluminum electrolytic capacitor is used instead, the converter mode-hops be- tween current mode and Burst Mode due to high ESR, causing the voltage comparator to trip as shown in Figure 5 ...
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... 220 F C Figure 7. Boost Converter with Simulated Load V OUT 100mV/DIV AC COUPLED 510mA I LOAD 10mA 1302 F07a LT1302/LT1302-5 to ground will eliminate this. Do not C 10 500 2W PULSE GENERATOR MTP3055EL 50 1302 F07 2ms/DIV 1302 F07b Figure 7b. 0.1 F from V to Ground. C Better, but More Improvement Needed ...
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... INDUCTOR CURRENT 1A/DIV 525mA I LOAD 25mA 1302 F07f Figure 8a LOAD Causes 220mV Undershoot to ground has been found SENSE IN SW LT1302-5 MBRS130LT3 0.1 F PGND V GND 220 F 220 F 10V 10V R1 3.3k 1ms/DIV 1302 F08a Pin Floating. Note 6kHz Burst Rate 25mA ...
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... LT1302 GND (BATTERY AND LOAD RETURN) Figure 9. Suggested Component Placement for LT1302 LT1302/LT1302-5 floating. Efficiency falls off at light load with T is recommended. This isolates the device IN pin to go below 200pF SHUTDOWN 1302 F09 ...
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... LT1302/LT1302 APPLICATIONS INFORMATION separate ground trace up under the package as shown. The battery and load return should go to the power side of the ground copper. Thermal Considerations The LT1302 contains a thermal shutdown feature which protects against excessive internal (junction) tempera- ture. If the junction temperature of the device exceeds the protection threshold, the device will begin cycling be- tween normal operation and an off state ...
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... Using the CS8 package with 100 sq. mm topside and backside heat sinking (312mW)(84 C/W) = 25.9 C rise With the N8 package 31 ambient, die temperature would be 101 LT1302/LT1302 ...
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... LT1302/LT1302-5 U TYPICAL APPLICATIONS 220 1.5V CELL SET LT1073 FB GND SW2 L1 = COILCRAFT DO3316-332 D1 = MOTOROLA MBRS130LT3 + C1 2 CELLS 100 F OUTPUT 12V 120mA 14 Single Cell to 5V/150mA Converter 5V/150mA OUTPUT 100k 100k SW1 SW LT1302 PGND + + 220 AVX TPSD476M016R0150 ...
Page 15
... Li-Ion Cell to 5.8V/600mA DC/DC Converter C2 220 F L1 10V LT1302 SHDN V C GND PGND 20k SHUTDOWN 10nF DUTY CYCLE = PEAK SWITCH VOLTAGE = V LT1302/LT1302-5 13V IN OUT + 22 F 330k 25V LT1121 1% SHDN ADJ GND 150k 1% 3.3V OUTPUT 400mA L2 MBRS130LT3 22 H 365k V 1% OUT 5.8V 600mA + ...
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... LT1302/LT1302-5 PACKAGE DESCRIPTION 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 PROTURSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm). 0.010 – 0.020 45 (0.254 – ...