ltc3108-1 Linear Technology Corporation, ltc3108-1 Datasheet
ltc3108-1
Related parts for ltc3108-1
ltc3108-1 Summary of contents
Page 1
... The LTC3108-1 is functionally equivalent to the LTC3108 except for its unique fixed V The LTC3108-1 is available in a small, thermally enhanced 12-lead (3mm × 4mm) DFN package and a 16-lead SSOP package. 5.25V ...
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... LTC3108-1 absoluTe MaxiMuM raTings SW Voltage ..................................................–0. Voltage ....................................................–0. Voltage (Note 5) .........................................– ...........................................–0. OUT2 OUT2_EN VAUX ....................................................15mA into VAUX pin conFiguraTion TOP VIEW VAUX 1 12 VSTORE OUT GND OUT2 VLDO 5 8 PGD PACKAGE ...
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... Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC3108-1 is tested under pulsed load conditions such that T ≈ The LTC3108-1E is guaranteed to meet specifications from ...
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... LTC3108-1 Typical perForMance characTerisTics 0V OUT 1000 1:50 RATIO 4.7n 1:100 RATIO 1:20 RATIO 10n 100 100 V (mV and Efficiency vs V VOUT 1:50 Ratio Transformer 3200 C1 = 4.7nF 2800 2400 EFFICIENCY (V = 4V) OUT 2000 1600 1200 800 400 0 0 100 200 ...
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... RATIO 1:100 RATIO 1:50 RATIO 1:100 RATIO 10 100 31081 G08 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 2.5 3 3.5 4 31081 G10 LTC3108 25°C, unless otherwise noted and Source Resistance 100 200 300 400 500 V OPEN-CIRCUIT (mV) IN 31081 G07 = 20mV 31081 G09 10µs/DIV 0.5 1 ...
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... LTC3108-1 Typical perForMance characTerisTics Start-Up Voltage Sequencing V = 50mV IN 1:100 RATIO TRANSFORMER C = 220µF OUT CSTORE = 470µ 2.2µF LDO 10sec/DIV V Ripple OUT 30µA LOAD C = 220µF OUT 20mV/ DIV 100ms/DIV Enable Input and V CH2 V OUT2 1V/DIV CH1 V OUT2_EN 1V/DIV 1ms/DIV 10mA LOAD ON V ...
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... Table 1. Regulated Voltage Using Pins VS1 and VS2 VS2 is OUT GND GND drops 9% OUT VAUX VAUX LTC3108-1 Select Pin 1. Connect this pin OUT (Pin 9/Pin 12): Enable Input for V OUT2 VS1 GND VAUX GND VAUX . V OUT2 ...
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... The LTC3108-1 can also be used to trickle charge a standard capacitor, supercapacitor or rechargeable battery, using energy harvested from a Peltier or photovoltaic cell. V OUT2 1 ...
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... Oscillator The LTC3108-1 utilizes a MOSFET switch to form a resonant step-up oscillator using an external step-up transformer and a small coupling capacitor. This allows it to boost input voltages as low as 20mV high enough to provide multiple regulated output voltages for powering other circuits. The frequency of oscillation is determined by the inductance of the transformer secondary winding and is typically in the range of 10kHz to 100kHz ...
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... must be handled by the V OUT Short-Circuit Protection All outputs of the LTC3108-1 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. Note: time not to scale. ...
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... Figure 1. Output Voltage Sequencing with V VSTORE (V) PGD (V) V (V) OUT VLDO (V) VAUX ( TIME (ms) Programmed for 3V (Time Not to Scale) OUT LTC3108 31081 F01a 31081f ...
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... V OUT indicating that enough energy is available for a burst. Input Voltage Sources The LTC3108-1 can operate from a number of low input voltage sources, such as Peltier cells, photovoltaic cells or thermopile generators. The minimum input voltage required for a given application will depend on the transformer turns ratio, the load power required, and the internal DC resistance (ESR) of the voltage source ...
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... Peltier cell is referred thermoelectric generator (TEG). The low voltage capability of the LTC3108-1 design allows it to operate from a TEG with temperature differentials as low as 1°C, making it ideal for harvesting energy in applications in which a temperature difference exists between two surfaces or between a surface and the am- bient temperature. The internal resistance (ESR) of most cells is in the range of 1Ω ...
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... For applications in which the temperature rise is too high for a solid-state thermoelectric device, a thermopile can be used as an energy source to power the LTC3108-1. Because of the higher output voltages possible with a thermopile generator, a lower transformer turns ratio can be used (typically 1:20, depending on the application) ...
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... Squegging is also encountered in RF oscillators and regenerative receivers. In the case of the LTC3108-1, squegging can occur when a charge builds up on the C2 gate coupling capacitor, such that the DC bias point shifts and oscillation is extinguished for a certain period of time, until the charge on the capacitor bleeds off, allowing oscillation to resume ...
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... Due to the very low input voltage the circuit may operate • • ) • TSTORE from, the connections to V and the SW and GND pins of the LTC3108-1 should be OUT designed to minimize voltage drop from stray resistance Q and able to carry currents as high as 500mA. Any small is the load on ...
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... Note that this must include any losses, such as storage capacitor leakage. Assume, for instance, that the charge current from the LTC3108-1 is 50µA and the total current drawn the sleep state is 17µA, including capacitor leakage. In addition, use the value of 150µF for the V ...
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... I ≥ 5 CHG Therefore, if the LTC3108-1 has an input voltage that al- lows 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 power required by this application is only 15.4µ ...
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... PAS1020LA3R0405 4.7µF 31081 TA03 T1 4.7nF 1:50 C1 220µF 330pF LTC3108-1 C2 499k SW VS2 VS1 V VAUX GND 2.2µF 31081 TA04 LTC3108 Illuminance VOUT " (2 Diameter Monocrystalline Cell) 10,000 INCANDESCENT LIGHT 1000 OUTDOOR LIGHT (CLOUDY) 100 FLOURESCENT LIGHT 10 100 1000 10,000 ILLUMINANCE (LUX) VSTORE ...
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... V V OUT2_EN OUT2_ENABLE VAUX GND 2.2µF 31081 TA05 AC Input Energy Harvester and Power Manager 5.25V C1 VSTORE OUT2 OUT2 > P-P PGD PGOOD LTC3108-1 C2 VLDO 4. OUT VS2 V VS1 V OUT2_ENABLE OUT2_EN VAUX GND 31081 TA06 2.2µ STORE 2.2V VLDO 2.2µF V OUT ...
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... V ≤ 3V OUT TYPICAL 5 4 MINIMUM LIMIT 150 200 250 300 350 400 450 500 550 V (mV) IN LTC3108 20mA V OUT2 0.1µF 10ms PGOOD 2.2V VLDO 2.2µ OUT 330µF 3 AVX TPSX337M004R0100 2.2V ENABLE ON OFF 10ms 31081 TA07 600 31081 TA07b ...
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... LTC3108-1 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 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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... BSC 1 .015 ± .004 × 45° .0532 – .0688 (0.38 ± 0.10) (1.35 – 1.75) 0° – 8° TYP .008 – .012 (0.203 – 0.305) TYP LTC3108-1 .189 – .196* (4.801 – 4.978) .009 (0.229 REF .150 – .157** (3.810 – 3.988 ...
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... C2 LTC3108-1 499k SW VS2 LPR6235-752SML VS1 V OUT2_EN VAUX GND 1µF VAUX 1nF 1:100 C1 VSTORE 330pF LTC3108-1 C2 499k SW VS2 LPR6235-752SML V VS1 OUT2_EN VAUX GND COMMENTS : 0.02V to 1V 3mm × 4mm DFN-12 and SSOP-16 Packages V : 450nA to 50mA 2mm × 3mm DFN-8 and MSOP-8 Packages V : 2.8V to 16V ...