lt3080-1 Linear Technology Corporation, lt3080-1 Datasheet
lt3080-1
Related parts for lt3080-1
lt3080-1 Summary of contents
Page 1
... The LT3080-1 is capable of supplying a wide output volt- age range. A reference current through a single resistor programs the output voltage to any level between zero and 36V. The LT3080-1 is stable with 2.2μF of ceramic capacitance on the output, not requiring additional ESR as is common with other regulators. ...
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... LT3080-1 ABSOLUTE MAXIMUM RATINGS V Pin Voltage ..................................... 40V, –0.3V CONTROL IN Pin Voltage ................................................ 40V, –0.3V SET Pin Current (Note 7) .....................................±10mA SET Pin Voltage (Relative to OUT) .........................±0.3V Output Short-Circuit Duration .......................... Indefi nite PIN CONFIGURATION TOP VIEW OUT 1 8 OUT OUT 3 6 SET ...
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... Exposure to any Absolute 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 LT3080-1 is tested and specifi ed under pulse load conditions such that T ≈ The LT3080-1 is 100% tested 25° ...
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... LT3080-1 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) 30801 G01 Offset Voltage Distribution N = 13250 –2 – DISTRIBUTION (mV) OS 30801 G04 Load Regulation 0 ΔI = 1mA TO 1.1A LOAD –5 V – OUT –10 –15 –20 CHANGE IN OFFSET VOLTAGE – ...
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... OUT I = 10mA LOAD 2.2μF OUT CERAMIC 0.1μF SET CERAMIC TIME (μs) LT3080-1 Dropout Voltage (Minimum V Pin Voltage) CONTROL 1.6 I LOAD 1.4 1.2 1 1mA LOAD 0.8 0.6 0.4 0.2 0 1.0 1.2 –50 – TEMPERATURE (°C) 30801 G11 Load Transient Response ...
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... LT3080-1 TYPICAL PERFORMANCE CHARACTERISTICS V Pin Current CONTROL 1.1A 20 LOAD DEVICE IN CURRENT LIMIT 1mA LOAD INPUT-TO-OUTPUT DIFFERENTIAL (V) *SEE NOTE 9 IN ELECTRICAL 30801 G19 CHARACTERISTICS TABLE Ripple Rejection - Single Supply 100 CONTROL OUT (NOMINAL) 90 RIPPLE = 50mV P– ...
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... Dropout specifi ca- tions). IN (Pins 7, 8/Pins 7, 8): This is the collector to the power device of the LT3080-1. 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 output voltage (see Dropout specifi ...
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... LT3080-1 BLOCK DIAGRAM APPLICATIONS INFORMATION The LT3080-1 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 LT3080-1 is especially well suited to applications needing multiple rails. The new architecture adjusts down to zero with a single resistor handling modern low volt- age digital IC’ ...
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... IC and spread it on the PC board. The LT3080-1 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 “ ...
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... Paralleling Devices LT3080-1’s may be directly paralleled to obtain higher output current. The SET pins are tied together and the IN pins are tied together. This is the same whether it’s in three terminal mode or has separate input supplies. The outputs are connected in common ...
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... Thermal Performance In this example, two LT3080-1 3mm × 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. Two tests were set up to measure the cooling performance and current sharing of these devices ...
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... Overload Recovery Like many IC power regulators, the LT3080-1 has safe oper- ating area (SOA) protection. The SOA protection decreases current limit as the input-to-output voltage increases and keeps the power dissipation at safe levels for all values of input-to-output voltage ...
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... APPLICATIONS INFORMATION Load Regulation Because the LT3080 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. Load regulation will be limited by the resistance of the connections between the regulator and the load. The data sheet specifi ...
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... LT3080-1 APPLICATIONS INFORMATION to give consideration to all sources of thermal resistance 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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... V – Power dissipation in the LT3080-1 now equals TOTAL The LT3080-1’s power dissipation is now only 30% com- pared to no series resistor. R Choose appropriate wattage resistors to handle and dis- sipate the power properly CONTROL R S LT3080 – 25mΩ ...
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... OUT(MAX) carries no more sipate the power properly. With this confi guration, the P LT3080-1 supplies only 0.36A. Therefore, load current can increase by 0.64A to 1.64A while keeping the LT3080-1 in its normal operating range CONTROL LT3080-1 IN ...
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... INSURES ZERO OUTPUT IN THE ABSENCE OF ANY OUTPUT LOAD Current Source LT3080 CONTROL + – 25mΩ SET IN LT3080-1 V CONTROL + – 2.2μF 25mΩ SET 100k LT3080-1 OUT OUT V OUT Q2* VN2222LL OUT 1Ω I OUT OUT 10μF 30801 TA03 30801f 17 ...
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... CONTROL + – 25mΩ OUT SET R1 2mA 24. SET 4.99k 1% Adding Soft-Start IN LT3080-1 V CONTROL + D1 IN4148 – 25mΩ SET IN LT3080-1 V CONTROL + C1 2.2μF – 25mΩ SET R1 C2 165k 0.01μ 0.5V + 2mA • R OUT SET V OUT 0.5V TO 10V R2 C 249Ω OUT 10μF 1% 30801 TA04 ...
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... TO 18V V CONTROL + – SET LT3080 CONTROL + – SET + 15μF 5V 10μF *4mV DROP ENSURES LT3080-1 IS OFF WITH NO-LOAD MULTIPLE LT3080-1’S CAN BE USED IN PARALLEL Lab Supply IN V CONTROL 25mΩ OUT IN V CONTROL 25mΩ 0.5Ω OUT 50k ...
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... Low Voltage, High Current Adjustable High Effi ciency Regulator 2. † 5.5V + 2× LTC3414 2.2MEG 100k 100μF PGOOD RUN/SS 1000pF SYNC/MODE SGND PGND * DIFFERENTIAL VOLTAGE ON LT3080-1 IS 0.6V SET BY THE V † MAXIMUM OUTPUT VOLTAGE IS 1.5V BELOW INPUT VOLTAGE 20 0.47μH 10k SW + 12.1k 2× I 100μF TH 470pF R T 2N3906 294k ...
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... TYPICAL APPLICATIONS CMDSH-4E 4. † 25V LT3493 10μF 1μF 100k SHDN 0.1μF GND *DIFFERENTIAL VOLTAGE ON LT3080-1 ≈ 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 V MBRM140 CONTROL ...
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... LT3080-1 PACKAGE DESCRIPTION 3.5 ±0.05 1.65 ±0.05 2.15 ±0.05 (2 SIDES) 0.25 ± 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS PIN 1 TOP MARK (NOTE 6) 0.200 REF 22 DD Package 8-Lead Plastic DFN (3mm × 3mm) (Reference LTC DWG # 05-08-1698) 0.675 ±0.05 PACKAGE OUTLINE 0.50 BSC 2.38 ±0.05 (2 SIDES) 1.65 ± 0.10 3.00 ±0.10 ...
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... TYP 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 LT3080-1 2.06 ± 0.102 (.081 ± .004) 1 1.83 ± 0.102 (.072 ± .004) 8 0.52 (.0205 REF 3.00 ± 0.102 (.118 ± .004) (NOTE 4) ...
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... FAX: (408) 434-0507 ● Paralleling Regulators IN LT3080-1 V CONTROL + – 25mΩ SET IN LT3080-1 V CONTROL + – 25mΩ 1μF SET 165k COMMENTS Fixed 2.85V, 3.3V, 3.6V, 5V and 12V Output 1V Dropout, Adjustable or Fixed Output, DD-Pak, SOT-223 Packages Okay for Sinking and Sourcing, S0-8 and SOT-223 Packages 340mV Dropout Voltage, Low Noise = 40μ ...