LXDC55FAAA-203 Micro DC-DC converter 1. Features Wide Input voltage range : 4.0V to 14.0V User Adjustable Output voltage : 0.8 to 5.3V Small footprint Buck converter for up to 1.5A output current application Low EMI noise by using an inductor-embedded ferrite substrate High efficiency using synchronous rectifier technology at 2MHz operation Superior transient response using quasi-fixed-frequency COT technology Seamless Power-Save Mode Transition Power-Good function ,Over current protection, Over temperature protection Quiescent Current of 150 μA (typ.) 2. Description The LXDC55F series is an easy-to-use synchronous step-down DC-DC converter optimized for applications with high power density. The device utilizes an inductor-embedded ferrite substrate, and the substrate eliminates radiated EMI noise and conduction noise efficiently. With its wide operating input voltage range of 4 V to 14 V, the devices are ideally suited for systems powered from either a Li-Ion or other batteries, as well as from 12-V intermediate power rails. It supports up to 1.5 A of continuous output current at output voltages between 0.8 V and 5.3 V The LXDC55F series utilizes a constant on time feedback technology and has superior 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 output voltage of LXDC55F series can be adjusted from 0.8 V to 5.3 V by using a resistor (RFB) between FB pin and GND pin. In terms of resistor value is calculated by RFB = 7.28/(Vout-0.8V) – 1.6 [kohm] The LXDC55F series has Power Good Output function. It’s to indicate whether the output voltage has reached its appropriate level or not. The device has an internal soft-start function to control the output voltage slope during start-up. In power-save mode, the devices show quiescent current of about 150 μA from VIN. Power-save mod e, it enters automatically and seamlessly if load is small, maintains high efficiency over the entire load range. 3. Typical Application Circuit 1 February 2016 LXDC55FAAA-203 Micro DC-DC converter 4. Mechanical details 4-1 Outline Top View Side View Bottom View 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. 1 Symbol EN I/O Input Description This is the ON/OFF control pin of the device. The device is in shutdown when the voltage to this pin is below 0.3V. Pulling this pin above 0.9V enables the device with soft start. This pin should not be left floating. EN=H: Device ON, EN=L: Device OFF 2 NC - No connection 3,4,5 Vin Input Vin pin supplies current to the LXDC55F internal regulator. 6,12,13,14 GND - Ground pin 7,8,9 Vout Output 10 PG Output 11 FB Input Regulated voltage output pin. Apply output load between this pin and GND. Power good voltage output pin (Open drain). This is to indicate whether the output voltage has reached its appropriate level or not. External resistor connection pin for output voltage setting 2 February 2016 LXDC55FAAA-203 Micro DC-DC converter 4-3. Functional Block Diagram 5. Ordering Information Part number Device Specific Feature MOQ LXDC55FAAA-203 Standard Type T/R, 1,000pcs/R LXDC55FAAAA203 Standard Type T/R, 300pcs/R 6. Electrical Specification 6-1 Absolute maximum ratings Parameter symbol rating Unit Input voltage Vin 16 V Enable voltage EN Vin V FB pin voltage FB 6 V PG pin voltage PG 6 Operating Ambient temperature Operating IC temperature Storage temperature V -40 to +85 o TIC -40 to +125 o TSTO -40 to +85 o Ta C C C 3 February 2016 LXDC55FAAA-203 Micro DC-DC converter 6-2 Electrical characteristics (Ta=25℃) Parameter Symbol Condition Min. Typ. Max. Unit Input voltage Vin 4 14 V Output voltage range Vout 0.8 5.3 V 2.8 V UVLO UVLO Standby current IinOFF Vin Falling 2.6 Hysteresis 2.7 200 Vin=12V,,EN=0.3V Quiescent current Iin0 Vin=12V, RFB=1312Ω (Vout=3.3V) Iout=0A Output voltage accuracy Vacc PWM mode Load current range Iout Over current protection OCP Auto-recovery mV 3 7 uA 150 200 uA -3.0 +3.0 % 0 1500 mA 1500 3500 mA Vin=12.0V, RFB=1.31kohm, Ripple voltage Vrpl (Vout=3.3V) 20 mV 87 % Iout=1A, BW=100MHz Vin=12.0V, RFB=1.31kohm, Efficiency EFF (Vout=3.3V) Iout=1000mA EN control voltage Switching frequency Power good threshold VENH ON ; Enable VENL OFF ; Disable 0.9 Vin V 0 0.3 V Vin=12V, RFB=1312Ω (Vout=3.3V) Iout=1000mA 2 MHz PGTHH Output voltage rising 95 % PGTHL Output voltage falling 90 % Vin=12V, Iout=0A 0,8 msec fosc Rise time TSU Power good sink current IPG 2 mA (*1) External capacitors (Cout:22uF) shall be placed near the module in order to proper operation. (*2) The above characteristics are tested using the application circuit on section 8. 4 February 2016 LXDC55FAAA-203 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. Io-Loss characteristics (Vin=12V, Vout=3.3V) Power Dissipation(mW) Io-Loss characteristics (Vin=12V, Vout=3.3V) 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. The amount of current de-rating is highly dependent on the environmental thermal conditions, i.e. PCB design, nearby components or effective air flows. Care should o especially be taken in applications where the device temperature exceeds 85 C. o The IC temperature of the device must be kept lower than the maximum rating of 125 C. It is generally recommended to take an appropriate de-rating to IC temperature for a reliable operation. A general de-rating for the temperature of semiconductor is 80%. MLCC capacitor’s reliability and lifetime are also depending on temperature and applied voltage stress. Higher temperature and/or higher voltage cause shorter lifetime of MLCC, and the degradation can be described by the Arrhenius model. The most critical parameter of the degradation is IR (Insulation Resistance). The below figure shows MLCC’s B1 life based on a failure rate reaching 1%. It should be noted that wear-out mechanisms in MLCC capacitor is not reversible but cumulative over time. 5 February 2016 LXDC55FAAA-203 Micro DC-DC converter Capacitor B1 Life vs Capacitor Case Temperature 100000000 Vin=12V Capacitor B1 Life (Thousand Hours) 10000000 Vin=10V 1000000 Vin=8V Vin=5V 100000 10000 1000 100 10 1 20 40 60 80 100 o Capacitor Case Temperature ( C ) 120 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. Considering the above figure, it should be checked if the expected B1 life of MLCC is acceptable or not. 6 February 2016 LXDC55FAAA-203 Micro DC-DC converter 7. Detailed Description Adjustable output voltage The output voltage of LXDC55F series can be adjusted from 0.8 V to 5.3 V by using a resistor (RFB) between FB pin and GND pin. In terms of resistor value is calculated by RFB = 7.28/(Vout-0.8V) – 1.6 [kohm]. Pulse-Width Modulation (PWM) Operation The LXDC55F series operates with pulse-width modulation in continuous-conduction mode (CCM). The device operates in PWM mode as long the output current is higher than half the inductor ripple current. To maintain high efficiency at light loads, the device enters power-save mode at the boundary to discontinuous conduction mode (DCM). This happens if the output current becomes smaller than half the inductor ripple current. Power-Save Mode Operation The LXDC55F series enters its built-in power-save mode seamlessly if the load current decreases. This secures a high efficiency in light-load operation. The device remains in power-save mode as long as the inductor current is discontinuous. In power-save mode, the switching frequency decreases linearly with the load current, maintaining high efficiency. The transition into and out of power-save mode happens within the entire regulation scheme and is seamless in both directions. UVLO (Under Voltage Lock Out) The input voltage (Vin) must reach or exceed the UVLO voltage (2.7Vtyp) before the device begins the start up sequence even when the EN pin is kept high. The UVLO function protects against unstable operation at low Vin levels Enable The device starts operation when EN is set high and starts up with soft start. For proper operation, the EN pin must be terminated to logic high and must not left floating. Pulling the EN pin to logic low forces the device shutdown. Power Good (PG) The LXDC55F series has a built-in power-good (PG) function to indicate whether the output voltage has reached its appropriate level or not. It can sink 2mA current and maintain its specified logic-low level. 100% Duty Cycle Operation The duty cycle of the buck converter is given by D = Vout/Vin and increases as the input voltage comes close to the output voltage. In this case, the device starts 100% duty-cycle operation, turning on the high-side switch 100% of the time. The high-side switch stays turned on as long as the output voltage is below the internal set point. This allows the conversion of small input-to-output voltage differences, e.g., for longest operation time of battery-powered applications. In 100% duty-cycle mode, the low-side FET is switched off. Over Current Protection The device integrates a current limit function to protect internal components against heavy load or short circuits.If the OCP event is removed, the output voltage recovers to the nominal value automatically. Thermal Shutdown As soon as the internal IC’s junction temperature exceeds 160℃ (typ), the device goes into thermal shutdown. The device continues its operation when the Internal IC’s junction temperature again falls below 140℃ (typ). 7 February 2016 LXDC55FAAA-203 Micro DC-DC converter 8. Test Circuit COUT: GRM21BB30J226 (22uF/6.3V MLCC) 9.Output Voltage adjustment Output voltage can be adjusted by using a resistor (RFB) between FB pin and GND pin. RFB = 7.28/(Vout-0.8V) – 1.6 [kohm] 8 February 2016 LXDC55FAAA-203 Micro DC-DC converter 10. 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 GND_S EN OFF Vin_S A V Enable SW * Evaluation board initial output Voltage setting : 3.3V ( resistor : 1.3kΩ + 12Ω ) The enable switch has three positions. 1. When it is toggled to “ON” side, the device starts operation. 2. When it is toggled to “OFF” side, the device stop operation and keep shut down status. 3. When it is set to middle of “ON” and “OFF”, the EN pin becomes floated and can be applied an external voltage through the EN terminal pin on the EVB. If you don’t apply external voltage to EN pin, the enable switch should not to be set to the middle position. ※The 47uF capacitor is for the evaluation kit only, and has been added to compensate for the long test cables. 9 February 2016 LXDC55FAAA-203 Micro DC-DC converter Typical Measurement Data (reference purpose only) (Ta=25℃) Efficency Vin=12.0V, Output Ripple-Noise Vin=12.0V, BW : 100MHz 10 February 2016 LXDC55FAAA-203 Micro DC-DC converter Load Regulation Vin=12.0V, Vout=0.8V Vin=12.0V, Vout=1.8V Vin=12.0V, Vout=3.3V Vin=12.0V, Vout=5.0V 11 February 2016 LXDC55FAAA-203 Micro DC-DC converter Load Transient Response ・Vin=12V, Vout=5V ・Vin=12V, Vout=3.3V 12 February 2016 LXDC55FAAA-203 Micro DC-DC converter Start Up Waveform ・Vin=12V, Vout=5V ・Vin=12V, Vout=3.3V 13 February 2016 LXDC55FAAA-203 Micro DC-DC converter 11.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 : 1.6mm Solder specimens onto test jig shown below. Apply pushing force at 0.5mm/s until electrode pads are peeled off or ceramics are broken. Pushing force is applied to longitudinal direction. 18 G (0) Pushing Direction 18 G (0) 18 G (0) 18 G (0) Test Methods Appearance : No severe damages Solder specimens on the testing jig (glass fluorine boards) shown in appended Fig.1 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 Soldering strength (Push Strength) QTY Specifications 9.8 N Minimum Specimen 4 5 Solderability of Termination Resistance to Soldering Heat (Reflow) 75% of the terminations is to be soldered evenly and continuously. Appearance No severe damages Electrical specifications Satisfy specifications listed in paragraph 6-2. Jig Immerse specimens first an ethanol solution of rosin, then in a Pb free solder solution for 3±0.5 sec. at 245±5 °C. Preheat : 150 °C, 60 sec. Solder Paste : Sn-3.0Ag-0.5Cu Flux : Solution of ethanol and rosin (25 % rosin in weight proportion) Preheat Temperature : 150-180 °C Preheat Period : 90+/-30 sec. High Temperature : 220 °C High Temp. Period : 20sec. Peak Temperature : 260+5/-0 °C Specimens are soldered twice with the above condition, and then kept in room condition for 24 h before measurements. 14 February 2016 LXDC55FAAA-203 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.+3/-0 30±3 Temperature：85±2 ℃ Humidity：80～90%RH Period：1000+48/-0 h Room Condition：2～24h Temperature：-40±2 ℃ Period：1000+48/-0 h Room Condition：2～24h QTY Result (NG) 18 G (0) 18 G (0) 18 G (0) 18 G (0) 10 ESD(Machine Model) C：200pF、R：0Ω TEST Voltage ：+/-100V Number of electric discharges：1 5 G (0) ESD(Human Body Model) C：100pF、R：1500Ω TEST Voltage ：+/-1000V Number of electric discharges：1 5 G (0) 11 15 February 2016 LXDC55FAAA-203 Micro DC-DC converter Fig.1 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 0.6 ・Reference purpose only. 16 February 2016 LXDC55FAAA-203 Micro DC-DC converter Fig.2 Testing board Unit：mm 100 ■： Land pattern is same as figure1 Glass-fluorine board t＝1.6mm Copper thickness over 35 mm 40 Mounted situation Unit：mm チップ Device 45 45 Test method Unit：mm 20 50 R230 たわみ量 deflection 17 February 2016 LXDC55FAAA-203 Micro DC-DC converter 13. Tape and Reel Packing 1）Dimensions of Tape (Plastic tape) (Unit : mm) Feeding direction 18 February 2016 LXDC55FAAA-203 Micro DC-DC converter 2） Dimensions of Reel 2-1. (Unit : mm) LXDC55FAAA-203 : 1,000pcs/reel 2±0.5 Φ100 φ13±0.2 Φ330 (13.5) 17.5±1.0 2-2. LXDC55FAAAA203 : 300pcs/reel Unit: mm 2±0.5 Φ60 φ13±0.2 Φ180 (13.0) 15.4±1.0 19 February 2016 LXDC55FAAA-203 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. Label 表示ラべル Desiccant 乾燥剤 Humidity 湿度 インジケ－タ Indicator 表示ラベル Label Anti-humidity 防湿梱包袋 Aluminum foil pack 4) Taping Diagrams(LXDC55F) [1] Feeding Hole ： As specified in (1) [2] Hole for chip ： As specified in (1) [3] Cover tape ： 50um in thickness [4] Base tape ： As specified in (1) [3] [1] [2] [3] [4] 1pin Mark Feeding hole Feedeng Direction Chip 20 February 2016 LXDC55FAAA-203 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）Material : Base tape ...... Plastic Reel and Cover tape ......Plastic Base tape, Reel and Cover tape have an anti-ESD function. 8） Peeling of force : 0.1~1.3 N in the direction of peeling as shown below. 0.7N max 0.1~1.3N 165 ~ 180 ° Cover tape Base tape 21 February 2016 LXDC55FAAA-203 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.). - Any excess mechanical shock including, but not limited to, sticking the packing materials by sharp object and dropping the product, shall not be applied in order not to damage the packing materials. ・After the packing opened, the product shall be stored at < 30 deg.C / < 60 %RH and the product shall be used within 168 hours. When the color of the indicator in the packing changed, the product shall be baked before soldering. This product is applicable to MSL3 (Based on IPC/JEDEC J-STD-020) 2. Handling Conditions: Be careful in handling or transporting the product. Excessive stress or mechanical shock may damage the product because of the nature of ceramics structure. Do not touch the product, especially the terminals, with bare ear hands. Doing so that may result in poor solderability. 3. Standard PCB Design (Land Pattern and Dimensions): All the ground terminals should be connected to the ground patterns. Furthermore, the ground pattern should be provided between IN and OUT terminals. Please refer to the specifications for the standard land dimensions. The recommended land pattern and dimensions are shown for a reference puerpose only. Electrical, mechanical and thermal characteristics of the product shall depend on the pattern design and material / thickness of the PCB. Therefore, be sure to check the product performance in the actual set. When using underfill materials, be sure to check the mechanical characteristics in the actual set. 22 February 2016 LXDC55FAAA-203 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. Contact Murata before use if concerning other soldering conditions. Reflow soldering standard conditions (example) Use rosin type flux or weakly active flux with a chlorine content of 0.2 wt % or less. 23 February 2016 LXDC55FAAA-203 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. However, if products are used under the following circumstances, it may damage products and leakage of electricity and abnormal temperature may occur. - In an atmosphere containing corrosive gas ( Cl2, NH3, SOx, NOx etc.). - In an atmosphere containing combustible and volatile gases. - In a dusty environment. - Direct sunlight - Water splashing place. - Humid place where water condenses. - In a freezing environment. If there are possibilities for products to be used under the preceding clause, consult with Murata before actual use. If static electricity is added to this product, degradation and destruction may be produced. Please use it after consideration enough so that neither static electricity nor excess voltage is added at the time of an assembly and measurement. If product malfunctions may result in serious damage, including that to human life, sufficient fail-safe measures must be taken, including the following: (1) Installation of protection circuits or other protective device to improve system safety (2) Installation of redundant circuits in the case of single-circuit failure 7. Input Power Capacity: Products shall be used in the input power capacity as specified in this specifications. Inform Murata beforehand, in case that the components are used beyond such input power capacity range. 24 February 2016 LXDC55FAAA-203 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. - Transportation equipment (vehicles, trains, ships, etc.). - Automobile equipment which includes the genuine brand of car manufacture, car factory-installed option and dealer-installed option. - Traffic signal equipment. - Disaster prevention / crime prevention equipment. - Data-procession equipment. - Application which malfunction or operational error may endanger human life and property of assets. - Application which related to occurrence the serious damage - Application of similar complexity and/ or reliability requirements to the applications listed in the above. ! Note: Please make sure that your product has been evaluated and confirmed against your specifications when our product is mounted to your product. Product specifications are subject to change or our products in it may be discontinued without advance notice. This catalog is for reference only and not an official product specification document, therefore, please review and approve our official product specification before ordering this product. 25 February 2016