Datasheet

ManualsBrandsMURATA POWER SOLUTIONS ManualsPSU ComponentsDC/DC converter (SMD) 3 A 11 W No. of outputs: 1 x

LXDC55KAAA-205

Micro DC-DC converter

Dec 2014

1. Features

 Small footprint Buck converter for up to 3A output current application

 Low EMI noise using an inductor-embedded ferrite substrate

 High efficiency using synchronous rectifier technology at 2MHz operation

 Wide input voltage range : 2.7 to 5.5V

 User Adjustable Output voltage : 0.8 to 3.6V

 Superior transient response using quasi-fixed-frequency COT technology

 Seamless Power-Save Mode Transition

 Powergood function

 Over current protection, Over temperature protection

2. Description

The LXDC55K series is a high-power density synchronous step down converter optimized for small solution size,

high efficiency and suitable for battery powered applications. To maximize efficiency, the converter operates in

PWM mode at heavy load and automatically enters Power Save Mode operation at light load currents. Power

Save Mode is entered automatically and seamlessly maintaining high efficiency over the entire load current range

The LXDC55K series utilizes a constant on time feedback technology and has excellent load transient response.

It has a unique circuit that roughly keeps the switching frequency constant, which makes it easy to filter the

switching noise. The device utilizes an inductor-embedded ferrite substrate, and the substrate eliminates radiated

EMI noise and conduction noise efficiently.

The output voltage of LXDC55K series can be adjusted from 0.8 V to 3.6 V by using a resistor (RFB) between FB

pin and GND pin. In terms of resistor value is calculated by RFB = 5.44/(Vout-0.8V) – 1.6 [kohm] .

The LXDC55K series has Power Good Output function. It’s to indicate whether the output voltage has reached its

appropriate level or not.

3. Typical Application Circuit

Summary of content (23 pages)

PAGE 1
LXDC55KAAA-205 Micro DC-DC converter 1. Features  Small footprint Buck converter for up to 3A output current application  Low EMI noise using an inductor-embedded ferrite substrate  High efficiency using synchronous rectifier technology at 2MHz operation  Wide input voltage range : 2.7 to 5.5V  User Adjustable Output voltage : 0.8 to 3.
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LXDC55KAAA-205 Micro DC-DC converter 4. Mechanical Details 4-1 Outline Unit:mm Mark Dimension Mark Dimension L 5.0 +/- 0.2 e 1.1 W 5.7 +/- 0.2 f 0.6 T 2.1 MAX g 0.35 a 0.25 h 0.6 b 0.7 i 0.35 c 0.4 j 1.0 d 0.8 4-2. Pin Function Pin No. Symbol I/O Description 1 EN Input This is the ON/OFF control pin of the device. The device is in shutdown when the voltage to this pin is below 0.4V. Pulling this pin above 1.0V enables the device with soft start.
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LXDC55KAAA-205 Micro DC-DC converter 4-3. Functional Block Diagram 5. Ordering Information Part number LXDC55KAAA-205 Device Specific Feature MOQ Standard Type T/R, 1,000pcs/R 6.
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LXDC55KAAA-205 Micro DC-DC converter 6-2 Electrical characteristics (Ta=25℃) Parameter Symbol Condition Min. Typ. Max. Unit Input voltage Vin 2.7 5.5 V Output voltage range Vout 0.8 3.6 V 2.3 V UVLO UVLO Standby current IinOFF Vin Falling 2.1 hysteresis 2.2 200 Vin=5V,EN=0.4V Quiescent current Iin0 Vin=5V, RFB=576Ω (Vout=3.3V) Iout=0A Output voltage accuracy Vacc PWM mode Load current range Iout Over current protection OCP Auto-recovery mV 2 6 uA 320 420 uA -2.
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LXDC55KAAA-205 Micro DC-DC converter 6-3 Thermal and Current De-rating Information The following figure shows the power dissipation and temperature rise characteristics example. These data are measured on Murata’s evaluation board of this device at no air-flow condition. The output current of the device may need to be de-rated if it is operated in a high ambient temperature or in a continuous power delivering application.
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LXDC55KAAA-205 Micro DC-DC converter The following steps should be taken before the design fix of user’s set for a reliable operation. o 1. The ambient temperature of the device should be kept below 85 C 2. The IC temperature should be measured on the worst condition of each application. The temperature must be o kept below 125 C. An appropriate de-rating of temperature and/or output current should be taken. 3. The MLCC temperature should be measured on the worst condition of each application.
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LXDC55KAAA-205 Micro DC-DC converter 7. Detailed Description Adjustable output voltage The output voltage of LXDC55K series can be adjusted from 0.8 V to 3.6 V by using a resistor (RFB) between FB pin and GND pin. In terms of resistor value is calculated by RFB = 5.44/(Vout-0.8V) – 1.6 [kohm] PWM Operation At medium to heavy load currents, the device operates with pulse width modulation (PWM). As the load current decreases, the converter enters the Power Save Mode operation reducing its switching frequency.
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LXDC55KAAA-205 Micro DC-DC converter 8. Test Circuit Cin : GRM21BB30J106 (10uF/6.3V MLCC) Cout : GRM21BB30J226 (22uF/6.3V MLCC) 9. Reference Land Pattern e f e f e (5) (4) (3) (6) (14) (13) (7) (8) (9) (2) (1) (12) (10) (11) b cb cd c b cb unit (mm) Mark Dimension b 0.7 c 0.4 d 0.8 e 1.1 f 0.
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LXDC55KAAA-205 Micro DC-DC converter 10. Output Voltage adjustment Output voltage can be adjusted by using a resistor (RFB) between FB pin and GND pin. RFB = 5.44/(Vout-0.8V) – 1.
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LXDC55KAAA-205 Micro DC-DC converter 11. Measurement Data Micro DC-DC Converter evaluation board (P2LX1568F) Measurement setup Power good Vout_S Load A GND_S Output voltage adjustment resistor Vout GND Vin V V GND EN ON EN OFF Vin_S A V GND_S Enable SW * Evaluation board initial output Voltage setting : 3.3V ( resistor : 560Ω + 16Ω ) The enable switch has three positions. 1. When it is toggled to “ON” side, the device starts operation. 2.
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LXDC55KAAA-205 Micro DC-DC converter Typical Measurement Data (reference purpose only) (Ta=25℃) Efficency Vin=5.0V, Output Ripple-Noise Vin=5.
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LXDC55KAAA-205 Micro DC-DC converter Load Regulation Vin=5.0V, Vout=0.8V Vin=5.0V, Vout=1.2V Vin=5.0V, Vout=1.8V Vin=5.0V, Vout=2.5V Vin=5.0V, Vout=3.
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LXDC55KAAA-205 Micro DC-DC converter Typical Measurement Data (reference purpose only) (Ta=25℃) Load Transient Response ・Vin=5.0V, Vout=3.3V ・Vin=5.0V, Vout=2.
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LXDC55KAAA-205 Micro DC-DC converter ・Vin=5.0V, Vout=1.8V ・Vin=5.0V, Vout=1.
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LXDC55KAAA-205 Micro DC-DC converter 12.Reliability Tests No. 1 2 3 Items Vibration Resistance Result (NG) 18 G (0) Frequency : 10~2000 Hz 2 Acceleration : 196 m/s Direction : X,Y,Z 3 axis Period : 2 h on each direction Total 6 h. Solder specimens on the testing jig (glass epoxy boards) shown in appended Fig.2 by a Pb free solder. The soldering shall be done either by iron or reflow and be conducted with care so that the soldering is uniform and free of defect such as by heat shock. Deflection : 1.
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LXDC55KAAA-205 Micro DC-DC converter No. 6 7 8 9 Items Specifications Test Methods High Temp. Exposure Temperature：85±2 ℃ Period：1000+48/-0 h Room Condition：2～24h Temperature Cycle Condition：100 cycles in the following table Humidity (Steady State) Appearance No severe damages Electrical specifications Satisfy specifications listed in paragraph 6-2. Low Temp. Exposure Step Temp(°C) Time(min) 1 Min. Operating Temp.+0/-3 30±3 2 Max. Operating Temp.
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LXDC55KAAA-205 Micro DC-DC converter 13. Tape and Reel Packing 1）Dimensions of Tape (Paper tape) (Unit : mm) 0.1 1.5+ 0 (0.3) 1.75±0.1 (5.5) (6.0) 12.0±0.2 (2.5) 4.0±0.1 (5.35) 2.0±0.05 8.0±0.1 Feeding direction 2） Dimensions of Reel (Unit : mm) 2±0.5 Φ100 φ13±0.2 Φ330 (13.5) 17.5±1.
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LXDC55KAAA-205 Micro DC-DC converter 3) PACKAGE Diagrams (Humidity proof Packing) Tape and reel must be sealed with the anti-humidity plastic bag. The bag contains the desiccant and the humidity indicator.
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LXDC55KAAA-205 Micro DC-DC converter 5） Leader and Tail tape Tail tape (No components) Components No components Leader tape (Cover tape alone) Over100mm Over160m Over400mm Feeding direction 6） The tape for chips are wound clockwise, the feeding holes to the right side as the tape is pulled toward the user. 7） Packaging unit: 1,000pcs./ reel 8）Material : Base tape ...... Plastic Reel and Cover tape ......Plastic Base tape, Reel and Cover tape have an anti-ESD function. 9） Peeling of force : 0.1~1.
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LXDC55KAAA-205 Micro DC-DC converter NOTICE 1. Storage Conditions: ・The product shall be stored without opening the packing under the ambient temperature from 5 to 35 deg.C and humidity from 20 to 70%RH. (Packing materials, in particular, may be deformed at the temperature over 40 deg.C.) ・The product left more than 6 months after reception, it needs to be confirmed the solderbility before used. - The product shall be stored in non corrosive gas (Cl2, NH3, SO2, Nox, etc.).
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LXDC55KAAA-205 Micro DC-DC converter 4. Soldering Conditions: Soldering is allowed up through 2 times. Carefully perform preheating ：△T less than 130 °C. When products are immersed in solvent after mounting, pay special attention to maintain the temperature difference within 100 °C. Soldering must be carried out by the above mentioned conditions to prevent products from damage.
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LXDC55KAAA-205 Micro DC-DC converter 5. Cleaning Conditions: The product is not designed to be cleaned after soldering. 6. Operational Environment Conditions: Products are designed to work for electronic products under normal environmental conditions (ambient temperature, humidity and pressure). Therefore, products have no problems to be used under the similar conditions to the above-mentioned.
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LXDC55KAAA-205 Micro DC-DC converter 8. Limitation of Applications: The products are designed and produced for application in ordinary electronic equipment (AV equipment, OA equipment, telecommunication, etc). If the products are to be used in devices requiring extremely high reliability following the application listed below, you should consult with the Murata staff in advance. - Aircraft equipment. - Aerospace equipment - Undersea equipment. - Power plant control equipment. - Medical equipment.