LTC3125 Linear Technology, LTC3125 Datasheet
LTC3125
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LTC3125 Summary of contents
Page 1
... In mobile computing, GSM and GPRS cards demand high current pulses well beyond the capability of the PC Card and CompactFlash slots. The LTC3125 in concert with a reservoir capacitor, keeps the slot power safely within its capabilities providing a high performance and simple solution. Synchronous rectifi ...
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... ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC3125EDCB#PBF LTC3125EDCB#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based fi nish parts. For more information on lead free part marking, go to: For more information on tape and reel specifi ...
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... Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC3125 is guaranteed to meet performance specifi cations from 0°C to 85°C. Specifi cations over –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls. Note 3: Specifi ...
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... LTC3125 TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency vs Load Current OUT 100 0.001 0.01 0.1 LOAD CURRENT (A) Average Input Current Limit vs Temperature 1.50 NORMALIZED TO 25°C 1.00 0.50 0 –0.50 –1.00 www.DataSheet4U.com –1.50 –50 – TEMPERATURE (°C) Burst Mode Threshold Current ...
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... NORMALIZED TO 25°C 0.25 0 –0.25 –0.50 –0.75 –1. –50 –30 –10 10 TEMPERATURE (°C) 3125 G15 BURST CURRENT 3125 G18 20ms/DIV LTC3125 (T = 25°C unless otherwise noted) A Oscillator Frequency vs Temperature 10 NORMALIZED TO 25° –2 –4 –6 –8 – –50 – ...
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... LTC3125 TYPICAL PERFORMANCE CHARACTERISTICS V and I During Soft-Start OUT IN V OUT 2V/DIV SHDN 5V/DIV INPUT CURRENT 200mA/DIV 4.5V OUT OUT L = 2.7μH PIN FUNCTIONS GND (Pin 1): Signal Ground. FB (Pin 2): Feedback Input to the Error Amplifi er. Connect the resistor divider tap to this pin. The top of the divider ...
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... LOGIC I ZERO CLK OSC CLK MODE CONTROL TSD WAKE + g m AVERAGING – V REF CIRCUIT I AVG ERROR AMP EXPOSED PAD GND 9 1 LTC3125 SEL WELL-SWITCH V OUT – ZERO COMP SLOPE COMP + V REF – SOFT START V CLAMP V 7 OUT R2 C OUT FB ...
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... N-chan- DS(ON) nel MOSFET switch and P-channel MOSFET synchronous rectifi er, the LTC3125 achieves high effi ciency over a wide range of load currents. Automatic Burst Mode operation maintains high effi ciency at very light loads, reducing the quiescent current to just 15μA. ...
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... V , the OUT IN cally leave Burst Mode operation. Once the LTC3125 has left Burst Mode operation and returned to normal operation, it will remain there until the output load is reduced below the burst threshold. Burst Mode operation is inhibited during start-up and soft- ...
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... Further, the GSM module is typically specifi operate over an input power range that is outside that allowed in the PCMCIA or CompactFlash bus power specifi cation. The LTC3125 is a high effi ciency boost converter with programmable input average current limit that provides the needed fl exibility when designing a GSM/GPRS power supply solution. The high effi ...
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... Molded chokes and some chip inductors usually do not have enough core area to support the peak inductor currents of 1.8A seen on the LTC3125. To minimize radiated noise, use a shielded inductor. See Table 1 for suggested components and suppliers. ...
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... 4.5V OUT C = 4.4mF OUT L = 2.2μ 44.2k PROG 2.7μ OUT 10μF LTC3125 CER SHDN 2.74M OFF ON PROG FB GND 1M 22.6k *WURTH 7440420027 **VISHAY 592D228X6R3X220H Waveforms of Input Current, V for Pulsed Load Current OUT V OUT 100mV/DIV INPUT CURRENT 500mA/DIV LOAD CURRENT 2A/DIV ...
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... OUT 500mV/DIV INPUT CURRENT 500mA/DIV LOAD CURRENT 1A/DIV V = 3.3V 200ms/DIV 2.5V OUT C = 10F OUT L = 2.2μ 22.6k PROG LTC3125 V OUT 4.5V, 2A PULSED LOAD (1154μs PW, 4.6ms PERIOD) 2200μF** 3 55mΩ TANT 3125 TA04a 3125 TA04b V OUT 2.5V SC** 1.07M 10F 60mΩ 1M 3125 TA05a 3125 TA05b ...
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... OUT C = 15F OUT_SERIES L = 2.2μ 44.2k PROG 3. with Selectable Input Current Limit 2.2μ OUT 3.3V ±10% 10μF LTC3125 CER SHDN OFF ON PROG FB GND 44.2k 300mA 500mA 28.7k M1 *TDK VLF4014ST-2R2M1R9 for Pulsed Input Current Limit OUT INPUT CURRENT 200mA/DIV M1 GATE DRIVE 5V/DIV V = 3.3V 2ms/DIV ...
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... ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE LTC3125 0.40 ± 0.10 TYP 5 8 1.35 ±0.10 1.65 ± ...
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... LTC3125 RELATED PARTS PART NUMBER DESCRIPTION LTC3400/LTC3400B 600mA (I ), 1.2MHz, Synchronous Step-Up DC/DC SW Converters LTC3421 3MHz, Synchronous Step-Up DC/DC Converter with SW Output Disconnect LTC3422 1. 3MHz Synchronous Step-Up DC/DC Converter with SW Output Disconnect LTC3426 1.5MHz Step-Up DC/DC Converter SW LTC3427 500mA (I ), 1.25MHz Synchronous Step-Up DC/DC Converter SW with Output Disconnect ...