LTC3108 Linear Technology, LTC3108 Datasheet
LTC3108
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LTC3108 Summary of contents
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... TEG (thermoelectric generators), thermopiles and small solar cells. The step-up topology operates from input voltages as low as 20mV. Using a small step-up transformer, the LTC3108 provides a complete power management solution for wireless sensing and data acquisition. The 2.2V LDO powers an external microprocessor, while the main output is programmed to one of four fi ...
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... LTC3108EDE#PBF LTC3108EDE#TRPBF LTC3108IDE#PBF LTC3108IDE#TRPBF LTC3108EGN#PBF LTC3108EGN#TRPBF LTC3108IGN#PBF LTC3108IGN#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. For more information on lead free part marking, go to: For more information on tape and reel specifi cations, go to: ...
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... Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC3108E is guaranteed to meet performance specifi cations from 0°C to 85°C. Specifi cations over the –40°C to 85°C operating temperature range are assured by design, characterization and correlation ...
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... LTC3108 TYPICAL PERFORMANCE CHARACTERISTICS I and Effi ciency vs V OUT 1:20 Ratio Transformer 3000 2500 EFFICIENCY 2000 1500 1000 I OUT 500 0 0 100 V I and Effi ciency OUT IN 1:100 Ratio Transformer 1200 I OUT 1000 800 EFFICIENCY 600 400 200 www.DataSheet4U.com 0 0 100 ...
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... OUT 1V/DIV 1V/DIV CH3, V LDO CH1 1V/DIV PGD 1V/DIV 5ms/DIV Enable Input and V OUT2 CH2, V OUT2 1V/DIV CH1 V OUT2_EN 1V/DIV 1ms/DIV 10mA LOAD ON V OUT2 C = 220μF OUT LTC3108 T = 25°C, unless otherwise noted. A LDO Dropout Voltage 0.20 0.18 0.16 0.14 0.12 0.10 0.08 0.06 0.04 0.02 0.00 0 0.5 1 1.5 2 2.5 3 3.5 4 LDO LOAD (mA) ...
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... LTC3108 PIN FUNCTIONS (DFN/SSOP) VAUX (Pin 1/Pin 2): Output of the Internal Rectifi er Cir- cuit and V for the IC. Bypass VAUX with at least 1μ capacitance. An active shunt regulator clamps VAUX to 5.25V (typical). VSTORE (Pin 2/Pin 3): Output for the Storage Capacitor or Battery. A large capacitor may be connected from this pin to GND for powering the system in the event the input voltage is lost ...
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... The LTC3108 can also be used to trickle charge a standard capacitor, supercapacitor or rechargeable battery, using energy harvested from a Peltier or photovoltaic cell. LTC3108 ...
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... C1) and the rectifi ers internal to the LTC3108. The rectifi er circuit feeds current into the VAUX pin, providing charge to the external VAUX capacitor and the other outputs. ...
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... Note that the VSTORE capacitor cannot supply large pulse currents OUT Short-Circuit Protection All outputs of the LTC3108 are current limited to protect against short-circuits to ground. Output Voltage Sequencing A timing diagram showing the typical charging and voltage sequencing of the outputs is shown in Figure 1. ...
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... LTC3108 OPERATION 5.0 2.5 0 3.0 2.0 1.0 0 5.0 2.5 0 3.0 2.0 1.0 0 5.0 2 Figure 1. Output Voltage Sequencing (with V www.DataSheet4U.com 10 VSTORE (V) PGD (V) V (V) OUT VLDO (V) VAUX ( TIME (ms) Programmed for 3.3V) OUT 3108 F01a 3108p ...
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... APPLICATIONS INFORMATION Introduction The LTC3108 is designed to gather energy from very low input voltage sources and convert it to usable output volt- ages to power microprocessors, wireless transmitters and analog sensors. Such applications typically require much more peak power, and at higher voltages, than the input voltage source can produce ...
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... Non-Boost Applications The LTC3108 can also be used as an energy harvester and power manager for input sources that do not require boosting. In these applications the step-up transformer can be eliminated. ...
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... The VSTORE capacitor can be sized using the following: C STORE Where 6μA is the quiescent current of the LTC3108, I the load on V LDO between bursts, I burst the duration of the burst the frequency of the bursts, TSTORE is the storage time required and V is the output voltage required ...
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... Figure 3. Example Component Placement for Two-Layer PC Board (DFN Package) 14 Due to the very low input voltage the circuit may operate from, the connections to V former and the SW and GND pins of the LTC3108 should be designed to minimize voltage drop from stray resistance and able to carry currents as high as 500mA. Any small PART NUMBER/SERIES ...
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... Assume, for instance, that the charge current from the LTC3108 is 50μA and the total current drawn on V the sleep state is 17μA, including capacitor leakage. In addition, use the value of 150μF for the V ...
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... IN ΔT = 1°C TO 20°C T1: COILCRAFT LPR6235-752SML 16 Therefore, if the LTC3108 has an input voltage that allows it to supply a charge current greater than 5.14μA, the application can support 100mA bursts lasting 5ms every hour. It can be determined that the sleep current of 5μA is the dominant factor because the transmit duty cycle is so small (0.00014%). Note that for a V average power required by this application is only 17μ ...
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... OUT OUT + 2.2μF 150mF 2.5V V OUT2_EN GND CAP-XX GZ115F AC Input Energy Havester and Power Manager VSTORE V V OUT2 OUT2 > 5V P-P PGD PGOOD LTC3108 C2 VLDO OUT + VS2 VS1 V V OUT2_ENABLE OUT2_EN VAUX GND 3108 TA06 1μ STORE 2.2V VLDO 2.2μF V OUT ...
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... LTC3108 PACKAGE DESCRIPTION 3.60 0.05 2.20 0.05 1.70 0.05 0.25 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED PIN 1 TOP MARK (NOTE 6) 0.200 REF www.DataSheet4U.com NOTE: 1. DRAWING PROPOSED VARIATION OF VERSION (WGED) IN JEDEC PACKAGE OUTLINE M0-229 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4 ...
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... TYP .008 – .012 (0.203 – 0.305) TYP INCHES LTC3108 .189 – .196* (4.801 – 4.978) .009 (0.229 REF .150 – .157** (3.810 – 3.988) ...
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... C1 VSTORE V 330pF LTC3108 C2 VLDO SW VS2 LPR6235-752SML VS1 V OUT2_EN VAUX GND 1μF VAUX 1nF 1:100 C1 VSTORE V 330pF LTC3108 C2 SW VLDO VS2 V LPR6235-752SML VS1 OUT2_EN VAUX GND COMMENTS V : 2.8V to 16V 1.25V; I OUT(MIN 1.6V to 20V Fixed 0. 2.6V to 19.2V ...