LTC3203 LINER [Linear Technology], LTC3203 Datasheet

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... The LTC3203-1/LTC3203B-1 have a user selectable fixed output voltage of 4. power LEDs or logic circuits. The FB pin of the LTC3203/LTC3203B can be used to program the desired output voltage. The parts are short- circuit and overtemperature protected and are available in a low profile (3mm × 3mm) DFN package. ...

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... U PACKAGE/ORDER I FOR ATIO +0. EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB *V ON LTC3203-1/LTC3203B- LTC3203/LTC3203B SEL ORDER PART NUMBER LTC3203EDD LTC3203EDD-1 LTC3203BEDD-1 LTC3203BEDD Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: Consult LTC Marketing for parts specified with wider operating temperature ranges ...

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... Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: Based on long-term current density limitations. Note 3: The LTC3203/LTC3203-1/LTC3203B/LTC3203B-1 are guaranteed to meet performance specifications from 0°C to 85°C. Specifications over the –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls ...

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... LTC3203/LTC3203-1 LTC3203B/LTC3203B TYPICAL PERFOR A CE CHARACTERISTICS ° µ 3.6V 2.2 F unless otherwise specified Load Current OUT (4.5V Output Setting) 4.65 4.60 4. 3. 2. 3.3V IN 4.35 4.30 1.5x MODE 2x MODE 4. 100 150 200 250 300 350 400 450 500 I (mA) LOAD 3203 G01 ...

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... W U TYPICAL PERFOR A CE CHARACTERISTICS No-Load Input Current vs Supply Voltage (LTC3203/LTC3203-1) 160 140 2x MODE 120 1.5x MODE 100 3.5 4.5 2 5.5 V (V) IN 3203 G10 Input and Output Ripple (1.5x Mode 20mV/DIV AC-COUPLED V OUT 20mV/DIV AC-COUPLED 500ns/DIV 2.2µ 10µF ...

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... OUT mode if the MODE pin is greater than V gives higher charge pump efficiency. If the MODE pin is less than V MODEL LTC3203B-1 operates in 2x mode, which gives a higher charge pump boost voltage. V (Pin 7): Input Supply Voltage with a more than 2.2µF low ESR ceramic capacitor to GND. ...

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... MODE 6 4 SHDN 0.91V 0.82V V 2 OUT OSCILLATOR + SWITCH CONTROL – – 8 3203 F01 LTC3203/LTC3203-1 LTC3203B/LTC3203B-1 LTC3203/LTC3203B + 2x/1.5x – SOFT-START AND SHUTDOWN CONTROL + 0.91V OSCILLATOR + SWITCH CONTROL – GND OUT – – ...

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... V LEDs while a regulated V logic circuits. The LTC3203/LTC3203B has a FB pin in place of the V pin that allows the output voltage to be programmed using an external resistive divider. Shutdown Mode When SHDN is asserted low, the LTC3203/LTC3203-1/ LTC3203B/LTC3203B-1 enter shutdown mode ...

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... IN OUT Short-Circuit/Thermal Protection The LTC3203/LTC3203-1/LTC3203B/LTC3203B-1 have built-in short-circuit current limit as well as over-tempera- ture protection. During a short-circuit condition, the chip will automatically limit the output current to approximately 1A. At higher temperatures the input voltage is high ...

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... U APPLICATIO S I FOR ATIO Power Efficiency The power efficiency (η) of the LTC3203/LTC3203-1/ LTC3203B/LTC3203B-1 in 1.5x mode is similar to that of a linear regulator with an effective input voltage of 1.5 times the actual input voltage. This occurs because the input current for a 1.5x fractional charge pump is approxi- mately 1.5 times the load current ideal regulating 1.5x charge pump the power efficiency would be given by: • ...

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... S external capacitors. Maximum Available Output Current Figure 3 shows how the LTC3203/LTC3203-1/LTC3203B/ LTC3203B-1 can be modeled as a Thevenin-equivalent circuit. Thus the maximum available output current and voltage can be calculated from the effective open-loop output resistance and the effective output voltage, 1.5V OL (in 1 ...

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... DC voltage. Likewise, excessive ESR on the output capacitor will tend to degrade the loop stability of the LTC3203/LTC3203-1/ LTC3203B/LTC3203B-1. The closed-loop output resis- tance of the LTC3203/LTC3203-1/LTC3203B/LTC3203B- 1 are designed to be 0.27Ω (at 1.5x mode). For a 100mA ...

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... Warning: Polarized capacitors such as tantalum or aluminum should never be used for the flying capacitors since their voltage can reverse upon start-up of the LTC3203/LTC3203-1/LTC3203B/LTC3203B-1. Low ESR ceramic capacitors should always be used for the flying capacitors. The flying capacitors control the strength of the charge pump. In order to achieve the rated output current necessary to have at least 2.2µ ...

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... APPLICATIO S I FOR ATIO Thermal Management For higher input voltages and maximum output current, there can be substantial power dissipation in the LTC3203/ LTC3203-1/LTC3203B/LTC3203B-1. If the junction tem- perature increases above approximately 150°C, the ther- mal shutdown circuitry will automatically deactivate the output ...

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... LTC3203B/LTC3203B Package 10-Lead Plastic DFN (3mm × 3mm) (Reference LTC DWG # 05-08-1699) 0.675 ±0.05 PIN 1 PACKAGE TOP MARK OUTLINE (SEE NOTE 6) 0.200 REF LTC3203/LTC3203 0.115 0.38 ± 0.10 TYP 6 10 3.00 ±0.10 1.65 ± 0.10 (4 SIDES) (2 SIDES 0.25 ± 0.05 0.75 ± ...

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... ThinSOT is a trademark of Linear Technology Corporation. Linear Technology Corporation 16 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● OUT LTC3203/ 10µF 10 LTC3203B – – MODE 4 47Ω 47Ω SHDN GND 9, 11 COMMENTS ...