OKLF-T/25-W12N Series www.murata-ps.com 90.75-Watt SMT Non-Isolated DC-DC Converter Typical unit FEATURES PRODUCT OVERVIEW iLGA inspectable Land Grid Array The OKLF-T/25-W12N is a 90 90.75-Watt 75-Watt SSMT non-isolated DC-DC converter for embedded applications featuring auto-compensation and the inspectable Land Grid Array (iLGA) format. The wide input range is 6.5 to 14Vdc. The maximum current is 25 Amps and the output is 0.6 to 3.3V, programmable via an external resistor. This model features an ultra-fast dynamic response of 30μs (typical 3.3Vout). With autocompensation, the converter automatically adjusts Auto-compensation of feedback loop Wide 6.5-14 VDC input range Non-isolated output adjustable from 0.6 to 3.3 Volts up to 25 Amps Fast dynamic response Sync function Power good output signal the feedback loop to provide optimal transient response. It also makes adjustments to compensate for changes in output capacitance over time, as capacitors age. Applications include powering CPUs, datacom/ telecom systems, programmable logic, networking, telecommunications equipment, and intermediate regulated bus voltage applications. Outstanding thermal performance and derating Input undervoltage shutdown Short circuit protection Negative On/Off enable control High efficiency at 94% (typ) Over temperature protection Remote sense Certified to UL/IEC 60950-1 safety approvals PG +Vin F1 On/Off Control +Vout t4XJUDIJOH Controller +Sense t'JMUFST t$VSSFOU4FOTF External DC Power Source –Sense R Load Trim Open = On Closed = Off (On/Off) Reference and Error Amplifier R Trim Common Sync Common Figure 1. Block Diagram Note: Murata Power Solutions strongly recommends an external input fuse, F1. See specifications. For full details go to www.murata-ps.com/rohs www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 1 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter PERFORMANCE SPECIFICATIONS SUMMARY AND ORDERING GUIDE Output Model Number ➀ OKLF-T/25-W12N-C Input Vout Iout (Amps, Power R/N (mV p-p) ➁ (Volts) ➀ max.) ➀ (Watts) Max. Regulation (max.) Line Load 0.6-3.3 ±0.3% ±0.3% 25 90.75 25 ➀ All specifications are at nominal line voltage, Vout=nominal and full load, +25°C. unless otherwise noted. All models are tested and specified with external 1 μF paralleled with 10 μF ceramic output capacitors and a 22 μF external input capacitor. All capacitors are low ESR types. Efficiency Vin nom. Range Iin, no load Iin, full load (Volts) (Volts) (mA) (Amps) Min. ➂ Typ. 12 6.5-14 120 8.045 92.5% 94% Dimensions inches (mm) 1.3 x 0.53 x 0.48 (33x 13.5 x12.2) ➁ Ripple and Noise (R/N) is shown at Vout=1V. See specs for details. ➂ Efficiency is shown for Vin nom, 3.3Vout. PART NUMBER STRUCTURE OK L F - T / 25 - W12 N - C Non-isolated PoL RoHS Hazardous Substance Compliance C = RoHS-6 (does not claim EU RoHS exemption 7b–lead in solder) iLGA Surface Mount (MSL Rating 2) Ultra fast dynamic response (Transient load response) On/Off Logic N = Negative Logic Trimmable Output Voltage Range 0.6-3.3Vdc Input Voltage Range 6.5-14Vdc Maximum Rated Output Current in Amps Note: Some model number combinations may not be available. See Ordering Guide above. Please contact Murata Power Solutions for availability. Product Label Because of the small size of these products, the product label contains a character-reduced code to indicate the model number and manufacturing date code. Not all items on the label are always used. Please note that the label differs from the product photograph. Here is the layout of the label: Model Number Product Code OKLF-T/25-W12N-C F00125 The manufacturing date code is four characters: Mfg. date code XXXXXX Product code YMDX Rev. Revision level Figure 2. Label Artwork Layout First character – Last digit of manufacturing year, example 2009 Second character – Month code (1 through 9 = Jan-Sep; O, N, D = Oct, Nov, Dec) Third character – Day code (1 through 9 = 1 to 9, 10 = 0 and 11 through 31 = A through Z) Fourth character – Manufacturing information The label contains three rows of information: First row – Murata Power Solutions logo Second row – Model number product code (see table) Third row – Manufacturing date code and revision level www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 2 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter FUNCTIONAL SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS Input voltage, continuous Input reverse polarity Output power Conditions ➀ Full power operation None, install external fuse Minimum 0 Typical/Nominal None 0 Maximum 16 Units Vdc Vdc W 90.75 Current-limited, no damage, Output current 0 25 A short-circuit protected Storage temperature range Vin = Zero (no power) -55 125 °C Absolute maximums are stress ratings. Exposure of devices to greater than any of these conditions may adversely affect long-term reliability. Proper operation under conditions other than those listed in the Performance/Functional Specifications Table is not implied nor recommended. INPUT Conditions ➀ ➂ Operating voltage range 6.5 12 14 Vdc Recommended external fuse Fast blow 20 A Turn on/start-up threshold Rising input voltage 5.3 5.5 5.7 Vdc Undervoltage shutdown 5 5.2 5.4 Vdc Internal filter type C-TYPE Input current Full load conditions Vin = nominal (3.3Vo set) 8.045 8.257 A Low line Vin @ min, 3.3 Vout 13.719 15.163 A Inrush transient 0.14 A2-Sec. Short circuit input current 43 mA No load input current 3.3Vout, Iout @ 0 120 150 mA No load input current 0.6V, Iout @ 0 70 100 mA Shut-down mode input current 30 mA Measured at input with specified filter 37 mA, pk-pk Reflected (back) ripple current ➁ GENERAL and SAFETY @ Vin nom, 3.3Vout 92.5 94 @ Vin min, 3.3Vout 93 94.5 @ Vin nom, 2.5Vout 91.5 93 Efficiency (12Vin @ 12A load current) @Vin nom, 1.8Vout 89.5 91 % @Vin nom, 1.5Vout 88 89.5 @Vin nom, 1.2Vout 86 87.5 @Vin nom, 1Vout 84 85.5 Certified to UL-60950-1, CSA-C22.2 No.60950-1, Safety Yes IEC/60950-1, 2nd edition Per Telcordia SR332, issue 1 class 3, ground TBD Hours x 106 Calculated MTBF ➃ fixed, Tambient=+25˚C DYNAMIC CHARACTERISTICS Switching frequency 475 500 525 KHz Startup time Power On to Vout regulated 120 mS Startup time Remote ON to 10% Vout 4.9 mS 50-100-50% load step, settling time to within Dynamic load response 30 50 μSec ±2% of Vout di/dt = 1 A/μSec. (3.3Vout) Dynamic load peak deviation same as above 100 200 mV FEATURES and OPTIONS Remote On/Off Control ➄ “N” suffix: Negative Logic, ON state Pin open=ON 0 1 V Negative Logic, OFF state 1.5 +Vin V Control Pin Shutdown Current open collector/drain 0.33 mA Power Good (standard) Vout Window for PGOOD: True PGOOD, Open Drain Configuration, Sinking -10 +10 % Vout Window for PGOOD: False 0.05 V www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 3 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter OUTPUT Total Output Power Voltage Nominal Output Voltage Range Setting Accuracy Output Voltage Overshoot - Startup Current Output Current Range Minimum Load Current Limit Inception ➅ Short Circuit Short Circuit Current ➆ Short Circuit Duration (remove short for recovery) Short circuit protection method Regulation Line Regulation Load Regulation Ripple and Noise ➇ Temperature Coefficient Maximum Capacitive Loading MECHANICAL (Through Hole Models) Outline Dimensions Conditions ➀ Minimum 0 See trim formula At 50% load, except 0.6Vout 0.6 -1 0 98% of Vnom., after warmup @3.3Vout 27.6 Typical/Nominal 90.75 25 No minimum load 32.6 Hiccup technique, autorecovery within ±1% of Vout 0.14 Output shorted to ground, no damage Continuous Maximum 90.75 Units W 3.3 1 1 Vdc % of Vnom. %Vo nom 25 A 37.6 A A Current limiting Vin=min. to max. Vout=nom. Iout=min. to max. 3.3Vo, 12Vin 1.8Vo, 12Vin 1Vo, 12Vin At all outputs ESR > 15mohm Low ESR Conditions ➀ ➂ ±0.3 ±0.3 65 40 25 3000 % % mV pk-pk mV pk-pk mV pk-pk % of Vnom./°C μF μF 1.3x0.53x0.48 33x13.5x12.19 0.0163 7.39 Inches mm Ounces Grams ±0.02 5000 LxWxH (Please refer to outline drawing) Weight ENVIRONMENTAL Operating Ambient Temperature Range Operating PCB Temperature Storage Temperature Thermal Protection/Shutdown full power, all output voltages; see derating curves No derating Vin = Zero (no power) Measured in center -40 85 °C -40 -55 130 100 125 135 °C °C °C 130 Notes ➀ Specifications are typical at +25 deg.C, Vin=nominal (+12V.), Vout=nominal (+3.3V), full load, external caps and natural convection unless otherwise indicated. Extended tests at higher power must supply substantial forced airflow. All models are tested and specified with external 1 μF paralleled with 10 μF ceramic output capacitors and a 22 μF external input capacitor. All capacitors are low ESR types. These capacitors are necessary to accommodate our test equipment and may not be required to achieve specified performance in your applications. However, Murata Power Solutions recommends installation of these capacitors. All models are stable and regulate within spec under no-load conditions. ➁ Input Back Ripple Current is tested and specified over a 5 Hz to 20 MHz bandwidth. Input filtering is Cin=2 x 100 μF tantalum, Cbus=1000 μF electrolytic, Lbus=1 μH. ➂ Note that Maximum Power Derating curves indicate an average current at nominal input voltage. At higher temperatures and/or lower airflow, the DC/DC converter will tolerate brief full current outputs if the total RMS current over time does not exceed the Derating curve. ➃ Mean Time Before Failure is calculated using the Telcordia (Belcore) SR-332 Method 1, Case 3, ISSUE 2, ground fixed controlled conditions, Tambient=+25 deg.C, full output load, natural air convection. ➄ The On/Off Control Input should use either a switch or an open collector/open drain transistor referenced to -Input Common. A logic gate may also be used by applying appropriate external voltages which not exceed +Vin. ➅ Short circuit shutdown begins when the output voltage degrades approximately 1% from the selected setting. ➆ “Hiccup” overcurrent operation repeatedly attempts to restart the converter with a brief, full-current output. If the overcurrent condition still exists, the restart current will be removed and then tried again. This short current pulse prevents overheating and damaging the converter. Once the fault is removed, the converter immediately recovers normal operation. ➇ Output noise may be further reduced by adding an external filter. At zero output current, the output may contain low frequency components which exceed the ripple specification. The output may be operated indefinitely with no load. www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 4 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter TYPICAL PERFORMANCE DATA Efficiency vs. Line Voltage and Load Current @ +25˚C. (Vout = 3.3V) 100 100 90 90 80 80 VIN = 6.5V VIN = 12V VIN = 14V VIN = 6.5V VIN = 12V VIN = 14V 70 Efficiency (%) 70 Efficiency (%) Efficiency vs. Line Voltage and Load Current @ +25˚C. (Vout = 2.5V) 60 50 40 60 50 40 30 30 20 20 10 10 0 0 0 5 10 15 20 25 30 0 5 10 Load Curre nt (Amps) Efficiency vs. Line Voltage and Load Current @ +25˚C. (Vout = 1.8V) 20 25 30 Efficiency vs. Line Voltage and Load Current @ +25˚C. (Vout = 1.2V) 100 100 90 90 80 80 VIN = 6.5V VIN = 12V VIN = 14V VIN = 6.5V VIN = 12V VIN = 14V 70 Efficiency (%) 70 Efficiency (%) 15 Load Curre nt (Amps) 60 50 40 60 50 40 30 30 20 20 10 10 0 0 0 5 10 15 20 25 30 0 5 10 Load Curre nt (Amps) 15 20 25 30 Load Curre nt (Amps) Efficiency vs. Line Voltage and Load Current @ +25˚C. (Vout = 1.0V) 100 90 80 VIN = 6.5V VIN = 12V VIN = 14V Efficiency (%) 70 60 50 40 30 20 10 0 0 5 10 15 20 25 30 Load Curre nt (Amps) www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 5 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter TYPICAL PERFORMANCE DATA Maximum Current Temperature Derating at Sea Level (Vin=12V, Vout=2.5V) 30 30 25 25 65 LFM 100 LFM 200 LFM 300 LFM 400 LFM 20 15 Output Current (Amps) Output Current (Amps) Maximum Current Temperature Derating at Sea Level (Vin=12V, Vout=3.3V) 10 5 65 LFM 100 LFM 200 LFM 300 LFM 400 LFM 20 15 10 5 0 0 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 20 25 30 35 40 45 Ambient Temperature (ºC) Maximum Current Temperature Derating at Sea Level (Vin=12V, Vout=1.8V) 60 65 70 75 80 85 90 30 25 25 65 LFM 100 LFM 200 LFM 300 LFM 400 LFM 20 15 Output Current (Amps) Output Current (Amps) 55 Maximum Current Temperature Derating at Sea Level (Vin=12V, Vout=1.2V) 30 10 5 65 LFM 100 LFM 200 LFM 300 LFM 400 LFM 20 15 10 5 0 0 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 20 25 30 35 40 45 Ambient Temperature (ºC) 50 55 60 65 70 75 80 85 90 Ambient Temperature (ºC) Maximum Current Temperature Derating at Sea Level (Vin=12V, Vout=1.0V) Maximum Current Temperature Derating at Sea Level (Vin=12V, Vout=0.6V) 30 30 25 25 65 LFM 100 LFM 200 LFM 300 LFM 400 LFM 20 15 Output Current (Amps) Output Current (Amps) 50 Ambient Temperature (ºC) 10 5 65 LFM 100 LFM 200 LFM 300 LFM 400 LFM 20 15 10 5 0 0 20 25 30 35 40 45 50 55 60 65 Ambient Temperature (ºC) 70 75 80 85 90 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 Ambient Temperature (ºC) www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 6 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter TYPICAL PERFORMANCE DATA Remote On/Off Start up (Vin=12Vout, Iout=25A, Vout=3.3V, Cout=100μf, Ta=+25°C) Ch1=Enable, Ch2=PowGood, Ch3=Vout Remote On/Off Start up (Vin=12Vout, Iout=0A, Vout=3.3Vout, Cout=100μf, Ta=+25°C) Ch1=Enable, Ch2=PowGood, Ch3=Vout Remote On/Off Start up (Vin=12Vout, Iout=25A, Vout=0.6V, Cout=100μf, Ta=+25°C) Ch1=Enable, Ch2=PowGood, Ch3=Vout Remote On/Off Start up (Vin=12Vout, Iout=0A, Vout=0.6V, Cout=100μf, Ta=+25°C) Ch1=Enable, Ch2=PowGood, Ch3=Vout www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 7 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter TYPICAL PERFORMANCE DATA Start up Delay (Vin=12V, Vout=3.3V, Iout=25A, Cload=100μf, T+25°C) Ch1=Vin, Ch3=Vout Start up Delay (Vin=12V, Vout=3.3V, Iout=0A, Cload=100μf, T+25°C) Ch1=Vin, Ch3=Vout Start up Delay (Vin=12V, Vout=0.6V, Iout=25A, Cload=100μf, T+25°C) Ch1=Vin, Ch3=Vout Start up Delay (Vin=12V, Vout=0.6V, Iout=0A, Cload=100μf, T+25°C) Ch1=Vin, Ch3=Vout www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 8 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter TYPICAL PERFORMANCE DATA Step Load Transient Response (Vin = 12V, Vout = 3.3V, Cload = 100μf, Iout = 0% to 50% of Step Load Transient Response (Vin = 12V, Vout = 3.3V, Cload = 100μf, Iout = 50% to 0% of full load, Ta = +25°C) Ch1 = Vout, Ch3 = Iout full load, Ta = +25°C) Ch1 = Vout, Ch3 = Iout Step Load Transient Response (Vin = 12V, Vout = 3.3V, Cload = 1000μf, Iout = 0% to 50% Step Load Transient Response (Vin = 12V, Vout = 3.3V, Cload = 1000μf, Iout = 50% to 0% of full load, Ta = +25°C) Ch1 = Vout, Ch3 = Iout of full load, Ta = +25°C) Ch1 = Vout, Ch3 = Iout Step Load Transient Response (Vin = 12V, Vout = 3.3V, Cload = 3000μf, Iout = 0% to 50% Step Load Transient Response (Vin = 12V, Vout = 3.3V, Cload = 3000μf, Iout = 50% to 0% of full load, Ta = +25°C) Ch1 = Vout, Ch3 = Iout of full load, Ta = +25°C) Ch1 = Vout, Ch3 = Iout www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 9 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter TYPICAL PERFORMANCE DATA Step Load Transient Response (Vin = 12V, Vout = 0.6V, Cload = 100μf, Iout = 50% to 0% of full load, Ta = +25°C) Ch1 = Vout, Ch3 = Iout Step Load Transient Response (Vin = 12V, Vout = 0.6V, Cload = 100μf, Iout = 0% to 50% of full load, Ta = +25°C) Ch1 = Vout, Ch3 = Iout Step Load Transient Response (Vin = 12V, Vout = 0.6V, Cload = 1000μf, Iout = 50% to 0% of full load, Ta = +25°C) Ch1 = Vout, Ch3 = Iout Step Load Transient Response (Vin = 12V, Vout = 0.6V, Cload = 1000μf, Iout = 0% to 50% of full load, Ta = +25°C) Ch1 = Vout, Ch3 = Iout Step Load Transient Response (Vin = 12V, Vout = 0.6V, Cload = 3000μf, Iout = 50% to 0% of full load, Ta = +25°C) Ch1 = Vout, Ch3 = Iout Step Load Transient Response (Vin = 12V, Vout = 0.6V, Cload = 3000μf, Iout = 0% to 50% of full load, Ta = +25°C) Ch1 = Vout, Ch3 = Iout www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 10 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter TYPICAL PERFORMANCE DATA Output Ripple and Noise( Vin=12V, Vout=3.3V, Iout=25A, Cout=1μf, Ta=+25°C) Ch3=Vout Output Ripple and Noise( Vin=12V, Vout=3.3V, Iout=0A, Cout=1μf, Ta=+25°C) Ch3=Vout Output Ripple and Noise( Vin=12V, Vout=0.6V, Iout=25A, Cout=1μf, Ta=+25°C) Ch3=Vout Output Ripple and Noise( Vin=12V, Vout=0.6V, Iout=0A, Cout=1μf, Ta=+25°C) Ch3=Vout Output Ripple and Noise( Vin=12V, Vout=3.3V, Iout=25A, Cout=100μf, Ta=+25°C) Ch3=Vout Output Ripple and Noise( Vin=12V, Vout=3.3V, Iout=0A, Cout=100μf, Ta=+25°C) Ch3=Vout www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 11 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter MECHANICAL SPECIFICATIONS (MSL Rating 2) PIN #1 END INDICATOR 1.30 0.53 0.867 0.972 1.057 1.177 0.677 0.487 0.232 0.297 0 0.48 0.445 0.405 ALL INTERFACIAL PADS COPLANAR WITHIN 0.006" INPUT/OUTPUT CONNECTIONS 0.430 0.165 0.155 15 14 0.215 0 0 1.057 0.867 0.677 0.487 0.297 0 3 Pin 1 Function On/Off 2 Vin 3 N/C 4 Ground 5 Vout 6 Trim 7 +Sense 8 –Sense 9 PG (PowerGood) 10 Sync DIMENSIONS ARE IN INCHES [mm] 14 Gnd TOLERANCES: 2 PLACE 0.02 3 PLACE 0.010 15 Gnd 16 Gnd ANGLES: 1 COMPONENTS SHOWN ARE FOR REFERENCE ONLY MATERIAL: PINS: COPPER ALLOY FINISH: (ALL PINS) GOLD (5u"MIN) OVER NICKEL (50u" MIN) Dimensions are in inches (mm shown for ref. only). Third Angle Projection Tolerances (unless otherwise specified): .XX ± 0.02 (0.5) .XXX ± 0.010 (0.25) Angles ± 1˚ Components are shown for reference only. www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 12 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter RECOMMENDED FOOTPRINT 1.320 0.058 0.060 7 6 5 4 3 0 12 13 10 16 2 1.057 1.177 11 9 0.867 0.232 0 0.076 X 0.128 (12 PLACES) 1 15 0.677 0.405 0.445 14 0.487 8 0.297 0.165 0 0.155 0.215 0.550 0.430 0.046 X 0.046 (4 PLACES) www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 13 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter TAPE AND REEL (MSL Rating 2) FE ED (U NW I ND ) DI RE CT IO TAPE AND REEL 7770233 SHIPPING KIT TAPE AND REEL WITH MSL2 PACKAGING (NOT SHOWN) 200 UNITS PER REEL N 0.27 0.65 PICKUP POINT 8.00 0.315 330.2 13.00 FEED (UNWIND) DIRECTION 0.059 SPROCKET HOLES (REF) PICK-UP NOZZLE LOCATION (TYP) 8.0mm [0.315"] 1.750 0.069 PIN #1 56.00 2.2 WIDTH 26.25 1.0 52.30 2.059 OBLONG HOLES ALONG THIS EDGE 2.00 0.079 POCKET TAPE DETAIL 20.000 0.787 PITCH 4.000 0.157 www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 14 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter TECHNICAL NOTES Output Voltage Adustment The output voltage may be adjusted over a limited range by connecting an external trim resistor (Rtrim) between the Trim pin and Ground. The Rtrim is recommended to have a ±0.5% accuracy (or better) with low temperature coefficient, ±100 ppm/°C or better. Mount the resistor close to the converter with very short leads or use a surface mount trim resistor. In the tables below, the calculated resistance is given. Do not exceed the specified limits of the output voltage or the converter’s maximum power rating when applying these resistors. Also, avoid high noise at the Trim input. However, to prevent instability, you should never connect any capacitors to Trim. OKLF-T/25-W12N Output Voltage 0.600 V 0.700 V 0.750 V 0.800 V 0.850 V 0.900 V 0.950 V 1.000 V 1.050 V 1.100 V 1.200 V 1.500 V 1.800 V 2.500 V 3.300 V Calculated Rtrim (KΩ) 0 kΩ 11.5 kΩ 18.2 kΩ 24.9 kΩ 31.6 kΩ 38.3 kΩ 45.3 kΩ 52.3 kΩ 59.0 kΩ 66.5 kΩ 73.2 kΩ 80.6 kΩ 86.6 kΩ 93.1 kΩ 100 kΩ Input Fusing Certain applications and/or safety agencies may require fuses at the inputs of power conversion components. Fuses should also be used when there is the possibility of sustained input voltage reversal which is not currentlimited. For greatest safety, we recommend a fast blow fuse installed in the ungrounded input supply line. The installer must observe all relevant safety standards and regulations. For safety agency approvals, install the converter in compliance with the end-user safety standard. Input Under-Voltage Shutdown and Start-Up Threshold Under normal start-up conditions, converters will not begin to regulate properly until the ramping-up input voltage exceeds and remains at the Start-Up Threshold Voltage (see Specifications). Once operating, converters will not turn off until the input voltage drops below the Under-Voltage Shutdown Limit. Subsequent restart will not occur until the input voltage rises again above the Start-Up Threshold. This built-in hysteresis prevents any unstable on/off operation at a single input voltage. Users should be aware however of input sources near the Under-Voltage Shutdown whose voltage decays as input current is consumed (such as capacitor inputs), the converter shuts off and then restarts as the external capacitor recharges. Such situations could oscillate. To prevent this, make sure the operating input voltage is well above the UV Shutdown voltage AT ALL TIMES. Start-Up Time Assuming that the output current is set at the rated maximum, the Vin to Vout Start-Up Time (see Specifications) is the time interval between the point when the ramping input voltage crosses the Start-Up Threshold and the fully loaded regulated output voltage enters and remains within its specified accuracy band. Actual measured times will vary with input source impedance, external input capacitance, input voltage slew rate and final value of the input voltage as it appears at the converter. These converters include a soft start circuit to moderate the duty cycle of its PWM controller at power up, thereby limiting the input inrush current. The On/Off Remote Control interval from On command to Vout regulated assumes that the converter already has its input voltage stabilized above the Start-Up Threshold before the On command. The interval is measured from the On command until the output enters and remains within its specified accuracy band. The specification assumes that the output is fully loaded at maximum rated current. Similar conditions apply to the On to Vout regulated specification such as external load capacitance and soft start circuitry. Recommended Input Filtering The user must assure that the input source has low AC impedance to provide dynamic stability and that the input supply has little or no inductive content, including long distributed wiring to a remote power supply. The converter will operate with no additional external capacitance if these conditions are met. For best performance, we recommend installing a low-ESR capacitor immediately adjacent to the converter’s input terminals. The capacitor should be a ceramic type such as the Murata Power Solutions GRM32 series or a polymer type. Initial suggested capacitor values are 10 to 22 μF, rated at twice the expected maximum input voltage. Make sure that the input terminals do not go below the undervoltage shutdown voltage at all times. More input bulk capacitance may be added in parallel (either electrolytic or tantalum) if needed. Recommended Output Filtering The converter will achieve its rated output ripple and noise with no additional external capacitor. However, the user may install more external output capacitance to reduce the ripple even further or for improved dynamic response. Again, use low-ESR ceramic (Murata Power Solutions GRM32 series) or polymer capacitors. Initial values of 10 to 47 μF may be tried, either single or multiple capacitors in parallel. Mount these close to the converter. Measure the output ripple under your load conditions. Use only as much capacitance as required to achieve your ripple and noise objectives. Excessive capacitance can make step load recovery sluggish or possibly introduce instability. Do not exceed the maximum rated output capacitance listed in the specifications. www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 15 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter Input Ripple Current and Output Noise All models in this converter series are tested and specified for input reflected ripple current and output noise using designated external input/ output components, circuits and layout as shown in the figures below. The Cbus and Lbus components simulate a typical DC voltage bus. Please note that the values of Cin, Lbus and Cbus will vary according to the specific converter model. I TO OSCILLOSCOPE CURRENT PROBE +VIN VIN LBUS + – + – CBUS Temperature Derating Curves The graphs in this data sheet illustrate typical operation under a variety of conditions. The Derating curves show the maximum continuous ambient air temperature and decreasing maximum output current which is acceptable under increasing forced airflow measured in Linear Feet per Minute (“LFM”). Note that these are AVERAGE measurements. The converter will accept brief increases in current or reduced airflow as long as the average is not exceeded. Note that the temperatures are of the ambient airflow, not the converter itself which is obviously running at higher temperature than the outside air. Also note that very low flow rates (below about 25 LFM) are similar to “natural convection,” that is, not using fan-forced airflow. CIN -VIN Murata Power Solutions makes Characterization measurements in a closed cycle wind tunnel with calibrated airflow. We use both thermocouples and an infrared camera system to observe thermal performance. CIN = 2 x 100μF, ESR < 700mΩ @ 100kHz CBUS = 1000μF, ESR < 100mΩ @ 100kHz LBUS = 1μH CAUTION: These graphs are all collected at slightly above Sea Level altitude. Be sure to reduce the derating for higher density altitude. Figure 3. Measuring Input Ripple Current +VOUT C1 CAUTION: If you operate too close to the thermal limits, the converter may shut down suddenly without warning. Be sure to thoroughly test your application to avoid unplanned thermal shutdown. C2 SCOPE RLOAD -VOUT C1 = 1μF C2 = 10μF LOAD 2-3 INCHES (51-76mm) FROM MODULE Figure 4. Measuring Output Ripple and Noise (PARD) Minimum Output Loading Requirements All models regulate within specification and are stable under no load to full load conditions. Operation under no load might however slightly increase output ripple and noise. Thermal Shutdown To prevent many over temperature problems and damage, these converters include thermal shutdown circuitry. If environmental conditions cause the temperature of the DC/DC’s to rise above the Operating Temperature Range up to the shutdown temperature, an on-board electronic temperature sensor will power down the unit. When the temperature decreases below the turn-on threshold, the converter will automatically restart. There is a small amount of hysteresis to prevent rapid on/off cycling. Output Current Limiting Current limiting inception is defined as the point at which full power falls below the rated tolerance. See the Performance/Functional Specifications. Note particularly that the output current may briefly rise above its rated value in normal operation as long as the average output power is not exceeded. This enhances reliability and continued operation of your application. If the output current is too high, the converter will enter the short circuit condition. Output Short Circuit Condition When a converter is in current-limit mode, the output voltage will drop as the output current demand increases. If the output voltage drops too low (approximately 98% of nominal output voltage for most models), the magnetically coupled voltage used to develop primary side voltages will also drop, thereby shutting down the PWM controller. Following a time-out period, the PWM will restart, causing the output voltage to begin ramping up to its appropriate value. If the short-circuit condition persists, another shutdown cycle will initiate. This rapid on/off cycling is called “hiccup mode.” The hiccup cycling reduces the average output current, thereby preventing excessive internal temperatures and/or component damage. A short circuit can be tolerated indefinitely. The “hiccup” system differs from older latching short circuit systems because you do not have to power down the converter to make it restart. The system will automatically restore operation as soon as the short circuit condition is removed. On/Off Control Pin The On/Off Control may be driven with external logic or by applying appropriate external voltages, which are referenced to -Input Common. The On/ Off Control Input should use either an open collector/open drain transistor or logic gate that does not exceed +VIN. www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 16 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter Power Good The Power Good output is TRUE at any time the output is within approximately ±10% of the voltage set point. Power Good basically indicates whether the converter is in regulation. Soldering Guidelines Murata Power Solutions recommends the specifications below when installing these converters. These specifications vary depending on the solder type. Exceeding these specifications may cause damage to the product. Your production environment may differ therefore please thoroughly review these guidelines with your process engineers. It is an Open-drain Power Good output that may be wired and connected with other devices. An external pull up resistor is needed. Reflow Solder Operations for surface-mount products (SMT) For Sn/Ag/Cu based solders: Sync Sync is used for frequency synchronization and phase alignment between devices. An external pull up resistor is needed. Synchronization provides a method where multiple slave devices are controlled by a single master device via open loop phase alignment of the PWM patterns. Preheat Temperature Less than 1 ºC. per second Time over Liquidus 45 to 75 seconds Maximum Peak Temperature 260 ºC. Cooling Rate Less than 3 ºC. per second For Sn/Pb based solders: Output Capacitive Load These converters do not require external capacitance added to achieve rated specifications. Users should only consider adding capacitance to reduce switching noise and/or to handle spike current load steps. Install only enough capacitance to achieve noise objectives. Excess external capacitance may cause regulation problems, degraded transient response and possible oscillation or instability. Preheat Temperature Less than 1 ºC. per second Time over Liquidus 60 to 75 seconds Maximum Peak Temperature 235 ºC. Cooling Rate Less than 3 ºC. per second Recommended Lead-free Solder Reflow Profile Peak Temp. 235-260° C 250 Temperature (°C) 200 Reflow Zone 150 Soaking Zone time above 217° C 45-75 sec 120 sec max 100 <1.5° C/sec High trace = normal upper limit Low trace = normal lower limit Preheating Zone 50 240 sec max 0 0 30 60 90 120 150 180 210 240 270 300 Time (sec) www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 17 of 18 OKLF-T/25-W12N Series 90.75-Watt SMT Non-Isolated DC-DC Converter Vertical Wind Tunnel IR Transparent optical window Unit under test (UUT) Murata Power Solutions employs a custom-designed enclosed vertical wind tunnel, infrared video camera system and test instrumentation for accurate airflow and heat dissipation analysis of power products. The system includes a precision low flow-rate anemometer, variable speed fan, power supply input and load controls, temperature gauges and adjustable heating element. Variable speed fan The IR camera can watch thermal characteristics of the Unit Under Test (UUT) with both dynamic loads and static steadystate conditions. A special optical port is used which is transparent to infrared wavelengths. The computer files from the IR camera can be studied for later analysis. IR Video Camera Heating element Precision low-rate anemometer 3” below UUT Ambient temperature sensor Airflow collimator Figure 5. Vertical Wind Tunnel Murata Power Solutions, Inc. 11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A. ISO 9001 and 14001 REGISTERED Both through-hole and surface mount converters are soldered down to a 10" x 10" host carrier board for realistic heat absorption and spreading. Both longitudinal and transverse airflow studies are possible by rotation of this carrier board since there are often significant differences in the heat dissipation in the two airflow directions. The combination of both adjustable airflow, adjustable ambient heat and adjustable Input/Output currents and voltages mean that a very wide range of measurement conditions can be studied. The airflow collimator mixes the heat from the heating element to make uniform temperature distribution. The collimator also reduces the amount of turbulence adjacent to the UUT by restoring laminar airflow. Such turbulence can change the effective heat transfer characteristics and give false readings. Excess turbulence removes more heat from some surfaces and less heat from others, possibly causing uneven overheating. Both sides of the UUT are studied since there are different thermal gradients on each side. The adjustable heating element and fan, built-in temperature gauges and no-contact IR camera mean that power supplies are tested in real-world conditions. This product is subject to the following operating requirements and the Life and Safety Critical Application Sales Policy: Refer to: http://www.murata-ps.com/requirements/ Murata Power Solutions, Inc. makes no representation that the use of its products in the circuits described herein, or the use of other technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained herein do not imply the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Specifications are subject to change without notice. © 2014 Murata Power Solutions, Inc. www.murata-ps.com/support OKLF-T/25-W12N.A03 Page 18 of 18