LT3085 LINER [Linear Technology], LT3085 Datasheet
LT3085
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LT3085 Summary of contents
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... A key feature of the LT3085 is the capability to supply a wide output voltage range. By using a reference current through a single resistor, the output voltage is programmed to any level between zero and 36V. The LT3085 is stable with 2.2μ ...
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... LT3085MPMS8E#TRPBF LEAD BASED FINISH TAPE AND REEL LT3085EDCB LT3085EDCB#TR LT3085EMS8E LT3085EMS8E#TR LT3085IDCB LT3085IDCB#TR LT3085IMS8E LT3085IMS8E#TR LT3085MPMS8E LT3085MPMS8E#TR 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 ...
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... Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2. Unless otherwise specifi ed, all voltages are with respect to V The LT3085 is tested and specifi ed under pulse load conditions such that ≅ The LT3085E is 100% tested 25° ...
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... LT3085 TYPICAL PERFORMANCE CHARACTERISTICS Set Pin Current 10.20 10.15 10.10 10.05 10.00 9.95 9.90 9.85 9.80 –50 – 100 125 150 TEMPERATURE (°C) 3085 G01 Offset Voltage Distribution N = 1676 –2 – DISTRIBUTION (mV) OS 3085 G04 Load Regulation 0 ΔI = 1mA TO 500mA LOAD V – –0.1 IN OUT –0.2 CHANGE IN REFERENCE CURRENT – ...
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... OUT – 10mA LOAD C = 2.2μF OUT –100 CERAMIC C = 0.1μF SET 6 CERAMIC 100 TIME (μs) LT3085 Dropout Voltage (Minimum V Pin Voltage) CONTROL 1.6 I 1.4 LOAD 1 100mA LOAD 1.0 0.8 0.6 0.4 0.2 0 450 500 –50 – TEMPERATURE (°C) 3085 G11 Load Transient Response ...
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... LT3085 TYPICAL PERFORMANCE CHARACTERISTICS V Pin Currrent CONTROL 500mA 12 LOAD 10 DEVICE IN 8 CURRENT LIMIT 1mA LOAD INPUT-TO-OUTPUT DIFFERENTIAL (V) 3085 G19 Ripple Rejection - Single Supply 100 100mA LOAD 500mA LOAD ...
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... IN (Pins 5, 6/Pins 7, 8): This is the collector to the power device of the LT3085. The output load current is supplied through this pin. For the device to regulate, the voltage at this pin must be more than 0.1V to 0.5V greater than the ...
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... LT3085 BLOCK DIAGRAM APPLICATIONS INFORMATION The LT3085 regulator is easy to use and has all the pro- tection features expected in high performance regulators. Included are short-circuit protection and safe operating area protection, as well as thermal shutdown. The LT3085 is especially well suited to applications needing multiple rails. The new architecture adjusts down to zero with a single resistor, handling modern low voltage digital IC’ ...
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... APPLICATIONS INFORMATION The LT3085 can be operated in two modes. Three terminal mode has the control pin connected to the power input pin which gives a limitation of 1.35V dropout. Alternatively, the “control” pin can be tied to a higher voltage and the power IN pin to a lower voltage giving 275mV dropout on the IN pin and minimizing the power dissipation ...
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... ESR are available for use to bypass these pins, but in cases where long wires connect the LT3085 inputs to a power supply (and also from ground of the LT3085 circuitry back to power supply ground), this causes insta- bilities. This happens due to the wire inductance forming an LC tank circuit with the input capacitor and not as a result of instability on the LT3085 ...
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... Figure 2. Ceramic Capacitor DC Bias Characteristics –20 –40 –60 –80 –100 –50 Figure 3. Ceramic Capacitor Temperature Characteristics LT3085 BOTH CAPACITORS ARE 16V, 1210 CASE SIZE, 10μF X5R Y5V BIAS VOLTAGE (V) 3085 F02 X5R ...
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... PC board, spreading the heat. Input resistors can further spread the heat if the input-to-output difference is high. Thermal Performance In this example, two LT3085 2mm × 3mm DFN devices are mounted on a 1oz copper 4-layer PC board. They are placed approximately 1.5 inches apart and the board is mounted vertically for convection cooling ...
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... Traditional low noise regulators bring the voltage refer- ence out to an external pin (usually through a large value resistor) to allow for bypassing and noise reduction of reference noise. The LT3085 does not use a traditional voltage reference like other linear regulators, but instead uses a reference current. That current operates with typi- cal noise current levels of 2.3pA/√ ...
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... Load Regulation Because the LT3085 is a fl oating device (there is no ground pin on the part, all quiescent and drive current is delivered to the load not possible to provide true remote load sensing ...
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... Normal power supply cycling or system “hot plugging and unplugging” does not do any damage. If the LT3085 is confi gured as a three-terminal (single supply) regulator with IN and V diode of the IN pin will protect the V Like any other regulator, exceeding the maximum input- ...
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... LT3085 APPLICATIONS INFORMATION from junction to ambient. This includes junction-to-case, case-to-heat sink interface, heat sink resistance or circuit board-to-ambient as the application dictates. Additional heat sources nearby must also be considered. For surface mount devices, heat sinking is accomplished by using the heat spreading capabilities of the PC board and its copper traces ...
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... Reducing Power Dissipation In some applications it may be necessary to reduce the power dissipation in the LT3085 package without sacrifi cing output current capability. Two techniques are available. The fi rst technique, illustrated in Figure 8, em- ploys a resistor in series with the regulator’s input. The ...
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... P • 0.5A = 0.26W choose appropriate wattage resistors to handle and dis- sipate the power properly. With this confi guration, the LT3085 supplies only 0.36A. Therefore, load current can increase by 0.3A to 0.143A while keeping the LT3085 in its normal operating range IN(MAX) = 0.5A and ...
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... OUT 2Ω 0.5W SET 100k Power Oscillator LT3085 + – OUT 10μF SET 6.3V, 150mA LIGHT BULB #47 47nF 2.21k 8.45k 220n 8.45k 121Ω 47nF LT3085 V OUT 3. 4.7μF 100μF 3085 TA02 I OUT 0A TO 0.5A 4.7μF 3085 TA03 V OUT 400Hz 4VAC P-P 4.7μF 20Ω 3085 TA22 ...
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... Using a Lower Value SET Resistor IN LT3085 + – OUT V OUT 0.5V TO 10V SET 1mA 49.9k 499Ω OUT 4.7μ SET 10k 3085 TA06 Low Dropout Voltage LED Driver CONTROL 100mA D1 LT3085 IN + – OUT SET R1 R2 24.9k 2.49Ω 3085 TA05 V = 0.5V + 1mA • R OUT SET 3085fa ...
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... CONTROL + D1 C1 1N4148 1μF – SET C2 R1 0.01μF 332k Coincident Tracking V IN LT3085 V CONTROL + – OUT SET R2 80.6k V OUT OUT1 2.5V 0.5A C2 4.7μF LT3085 V OUT OUT 3.3V 0.5A C OUT 4.7μF 3085 TA07 IN LT3085 CONTROL + – V OUT3 OUT 5V 0.5A SET 169k V 4.7μF OUT2 3.3V 3085 TA08 0.5A C3 4.7μF 3085fa 21 ...
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... IN LT3085 V CONTROL + – OUT SET + R SET 15μF 2M Ramp Generator IN LT3085 V CONTROL + 1μF – OUT SET VN2222LL 1μF LT3085 + – OUT V OUT 0V TO 10V + SET 4.7μF 100μ 3085 TA09 V OUT 0. 20V OUT V = 10μA • R 4.7μF OUT SET 3085 TA10 ...
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... TYPICAL APPLICATIONS V 5V 10μF *4mV DROP ENSURES LT3085 IS OFF WITH NO LOAD MULTIPLE LT3085’S CAN BE USED Reference Buffer IN LT3085 CONTROL + – OUT INPUT SET OUTPUT LT1019 C1 GND 1μF Ground Clamp IN LT3085 IN V CONTROL + – OUT 1μF SET 1N4148 5k 3085 TA13 ...
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... Low Voltage, High Current Adjustable High Effi ciency Regulator † 2. 100μF LTC3414 2.2MEG 100k ×2 PGOOD RUN/SS 1000pF SYNC/MODE SGND *DIFFERENTIAL VOLTAGE ON LT3085 IS 0.6V SET BY THE V † MAXIMUM OUTPUT VOLTAGE IS 1.5V BELOW INPUT VOLTAGE 24 0.47μ 100μ ×2 12.1k 470pF R T 2N3906 ...
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... TYPICAL APPLICATIONS CMDSH-4E † 4.5V TO 25V V IN 10μF 1μF LT3493 100k SHDN 0.1μF *DIFFERENTIAL VOLTAGE ON LT3085 ≈ 1.4V SET BY THE TPO610L P-CHANNEL THRESHOLD. † MAXIMUM OUTPUT VOLTAGE IS 2V BELOW INPUT VOLTAGE Adjustable High Effi ciency Regulator* BOOST 0.1μF 10μH SW 68μF MBRM140 TP0610L ...
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... LT3085 PACKAGE DESCRIPTION 1.65 0.05 3.55 0.05 (2 SIDES) 2.15 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS PIN 1 BAR TOP MARK (SEE NOTE 6) 0.200 REF NOTE: 1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (TBD) 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE 5 ...
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... DETAIL “A” (.193 .006) 0° – 6° TYP 1 0.53 0.152 1.10 (.021 .006) (.043) DETAIL “A” MAX SEATING PLANE 0.22 – 0.38 (.009 – .015) 0.65 TYP (.0256) BSC LT3085 2.06 0.102 (.081 .004) 1.83 0.102 (.072 .004) 0.52 (.0205 REF 3.00 0.102 (.118 .004) (NOTE ...
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... McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● Paralleling Regulators IN LT3080 V CONTROL + – OUT 10mΩ SET LT3085 CONTROL + – OUT 20mΩ 1μF SET 165k COMMENTS Fixed 2.85V, 3.3V, 3.6V, 5V and 12V Output 300mV Dropout Voltage, Low Noise = 20μ ...