UEI15 Series www.murata-ps.com Isolated Wide Input Range 15-Watt DC/DC Converters Featuring a full 15 Watt or greater output in one square inch of board area, the UEI series isolated DC/DC converter family offers efficient regulated DC power for printed circuit board mounting. Typical unit FEATURES PRODUCT OVERVIEW Small footprint DC/DC converter, ideal for high current applications Wide range 4:1 inputs on the 0.96" x 1.1" x 0.36" converter are either 9 to 36 Volts DC (Q12 models) or 18 to 75 Volts DC (Q48 models), ideal for batterypowered and telecom equipment. The industrystandard pinout fits larger 1" x 2" converters. Fixed output voltages from 3.3 VDC to 15 VDC are regulated to within ±0.2% or less and may be trimmed within ±10% of nominal output. Applications include small instruments, area-limited microcontrollers, computer-based systems, data communications equipment, remote sensor systems, vehicle and portable electronics. The UEI 15W series includes full magnetic and optical isolation up to 2250 Volts DC (basic insulation). For connection to digital systems, the outputs offer fast settling to current step loads and tolerance of higher capacitive loads. Excellent ripple Industry standard 0.96" x 1.1" X 0.36" open frame package and pinout Wide range input voltages 9-36 and 18-75 Vdc Double lead-free assembly and attachment for RoHS standards Isolation up to 2250 VDC (basic) Up to 15 Watts or greater total output power with overtemperature shutdown High efficiency synchronous rectifier forward topology Stable no-load operation with no required external components and noise specifications assure compatibility to circuits using CPU’s, ASIC’s, programmable logic and FPGA’s. For systems requiring controlled startup/shutdown, an external switch, transistor or digital logic may be used to activate the remote On/Off control. A wealth of self-protection features avoid both converter and external circuit problems. These include input undervoltage lockout and overtemperature shutdown. The outputs current limit using the “hiccup” autorestart technique and the outputs may be short-circuited indefinitely. Additional features include output overvoltage and reverse conduction elimination. The high efficiency offers minimal heat buildup and “no fan” operation. Usable -40 to 85°C temperature range (with derating) Designed to meet UL 60950-1, CAN/CSAC22.2 No. 60950-1, IEC60950-1, EN60950-1 safety approvals SIMPLIFIED SCHEMATIC +VOUT +VIN Extensive self-protection shut down features –VOUT On/Off Control Control GATE DRIVE ISOLATION BARRIER −VIN ISOLATION Reference, Trim & Error Amplifier TRIM 3.3V and 5VOUT models only. Typical topology is shown. For full details go to www.murata-ps.com/rohs www.murata-ps.com Technical enquiries email: [email protected], tel: +1 508 339 3000 MDC_UEI15W.B24 Page 1 of 13 UEI15 Series Isolated Wide Input Range 15-Watt DC/DC Converters PERFORMANCE SPECIFICATIONS AND ORDERING GUIDE ➀ Output Input R/N (mVp-p) ➁ Regulation (Max.) Root Models ➀ VOUT IOUT Power Typ. (V) (A)e (W) Max. Line Load IIN = no VIN Nom. Range load (V) (V) (mA) Min. Typ. 89% UEI15-033-Q12P-C 3.3 4.5 14.85 60 90 ±0.05% ±0.1% 24 9-36 43 0.71 86.5% UEI15-033-Q48N-C 3.3 5 16.5 60 90 ±0.2% ±0.2% 48 18-75 24 0.4 86.5% 88.8% 86.3% 87.3% UEI15-050-Q12P-C 5 3 15 70 125 ±0.05% ±0.075% 24 9-36 41 0.72 UEI15-050-Q48N-C 5 3 15 60 95 ±0.05% ±0.06% 48 18-75 28 0.36 84.3% 86.0% UEI15-120-Q12P-C 12 1.3 15.6 110 150 ±0.05% ±0.05% 24 9-36 15 0.77 82.3% 84.5% UEI15-120-Q48N-C 12 1.3 15.6 85 120 ±0.075% ±0.05% 48 18-75 15 0.76 83.3% 85% 85% UEI15-150-Q12P-C 15 1.1 16.5 130 175 ±0.05% ±0.05% 24 9-36 18 0.81 83.5% UEI15-150-Q48N-C 15 1.1 16.5 80 120 ±0.05% ±0.05% 48 18-75 14 0.4 83.3% 85.3% ➀ Please refer to the part number structure for additional options and complete ordering part numbers. ➁ All specifications are typical at nominal line voltage and full load, +25 deg.C. unless otherwise noted. See detailed specifications. Open Frame Package – C75 Efficiency IIN = full load (A) (inches) (mm) Case Pinout 1.1×0.96×0.36 27.9×24.4×9.1 P22 e Minimum output load for UEI15-033-Q12, UEI15-120-Q12 and UEI15-050-Q12 is 10% of maximum current. PART NUMBER STRUCTURE UEI15 - 033 - Q12 Unipolar Wide Input 15-Watt Series Nominal Output Voltage in Tenths of a Volt P-C RoHS-6 Hazardous Substance Compliance On/Off Control Polarity: P = Positive N = Negative Input Voltage Range Q12 = 9-36V Q48 = 18-75V www.murata-ps.com Note: Some model number combinations may not be available. Contact Murata Power Solutions. Technical enquiries email: [email protected], tel: +1 508 339 3000 MDC_UEI15W.B24 Page 2 of 13 UEI15 Series Isolated Wide Input Range 15-Watt DC/DC Converters MECHANICAL SPECIFICATIONS, OPEN FRAME PHYSICAL CHARACTERISTICS TOP VIEW 27.9 1.10 Case 75 PIN #1 24.4 0.96 Pin Material Pin Diameter Pin Finish Weight Electromagnetic Interference Flammability Rating Safety (designed to meet) Copper alloy 0.04" (1.016mm) Gold plate 0.352 oz./10 grams FCC part 15, class B, EN55022 UL 94V-0 UL/cUL 60950-1, CAN/CSAC22.2-60950-1, IEC/EN 60950-1 Dimensions are in inches (mm shown for ref. only). Third Angle Projection INPUT/OUTPUT CONNECTIONS Pin Function 1 SIDE VIEW Tolerances (unless otherwise specified): .XX ± 0.02 (0.5) .XXX ± 0.010 (0.25) Angles ± 1˚ 9.1 0.36 Components are shown for reference only. + Vin 2 - Vin 3 + Vout 4 Output Trim 5 - Vout 6 On/Off Control* *The Remote On/Off can be provided with either positive (P suffix) or negative (N suffix) polarity .040 .002 PIN WITH .071 .002 SHOULDER 6X AT PINS 1-6 END VIEW BOTTOM VIEW #5 10.16 0.400 CL 0.428 REF #6 #2 #4 10.16 0.400 #1 5.08 0.200 CL 10.16 0.400 #3 2.54 0.100 CL 20.32 0.800 www.murata-ps.com 4.8 0.19 Technical enquiries email: [email protected], tel: +1 508 339 3000 MDC_UEI15W.B24 Page 3 of 13 UEI15 Series Isolated Wide Input Range 15-Watt DC/DC Converters INPUT CHARACTERISTICS Model Family UEI15-033-Q12 UEI15-033-Q48 UEI15-050-Q12 UEI15-050-Q48 UEI15-120-Q12 UEI15-120-Q48 UEI15-150-Q12 UEI15-150-Q48 UnderStart-up voltage threshold Shutdown V V Reflected (back) Ripple Current mA pk-pk Input Current Inrush Transient A2sec Output Short Standby Circuit Low Line Mode mA A mA 9.5 8.6 1.86 16.7 15.6 1.04 2 9.5 8.5 1.90 4 16.7 15.6 9.5 16.7 9.5 16.7 8.4 15.6 8.4 16.2 30 0.05 50 Remote On/Off Control Internal Reverse Input Polarity On/Off Positive Logic Negative Logic "N" model Filter Protec- Current blank model Type tion mA suffix suffix Recommended Fuse A 4 0.96 1 2.04 1.02 2.13 1.06 C 2 L 4 1.5 4 2 C None see note 15 1 OFF=Gnd pin or –0.7 to +1.2V max. ON=open pin or +5.8 to +15V max. OFF=open pin or +5.8 to + 15V max. ON=Gnd pin or –0.7 to +1.2V max. Model Family Efficiency Line/Load Regulation Ripple/Noise (20 MHz bandwidth)8 V 4.5 1,000 3.9 5.9 See Ordering Guide ±1 ±10 17 5.9 ±0.02 14.1 470 Magnetic feedback See ordering guide 15 18 20 ISOLATION CHARACTERISTICS UEI15-033-Q12 UEI15-033-Q48 UEI15-050-Q12 UEI15-050-Q48 UEI15-120-Q12 UEI15-120-Q48 UEI15-150-Q12 UEI15-150-Q48 Overvoltage protection Voltage Output Range Model Family UEI15-033-Q12 UEI15-033-Q48 UEI15-050-Q12 UEI15-050-Q48 UEI15-120-Q12 UEI15-120-Q48 UEI15-150-Q12 UEI15-150-Q48 VOUT Capacitive Loading Max. Accuracy Adjustment Temperature Low ESR <0.02Ω Max, 50% Load Range Coefficient resistive load % of VNOM % of VNOM % of VOUT /ºC μF IOUT Max. mA OV protection method OUTPUT CHARACTERISTICS DYNAMIC CHARACTERISTICS Input to Output Min. Vdc Isolation Resistance Min. MΩ Isolation Capacitance pF 2000 10 1000 2250 10 1500 2000 10 1500 2250 10 1000 2000 10 1000 2250 10 1000 2000 10 1500 2250 10 1000 Isolation Safety Rating Basic insulation Dynamic Load Response (50-75-50% load step) μSec to 1% VOUT Model Family UEI15-033-Q12 UEI15-033-Q48 UEI15-050-Q12 UEI15-050-Q48 UEI15-120-Q12 UEI15-120-Q48 UEI15-150-Q12 UEI15-150-Q48 Start-up Time Switching VIN to VOUT regulated Remote On/Off to VOUT Frequency (Max.) mSec regulated max.) mSec KHz 350 350 100 150 350 50 50 375 340 350 100 340 380 MISCELLANEOUS CHARACTERISTICS Model Family Current Limit Short Inception 98% of Circuit Vout, after warmup Protection A Method Short Circuit Current A Short Circuit Duration (output shorted to ground)➀ Operating Temperature Range Prebiased setup Calculated MTBF Hours ④ UEI15-033-Q12 6.0 2 x 106 UEI15-033-Q48 7.2 3.49 x 106 UEI15-050-Q12 4.6 UEI15-050-Q48 4.5 UEI15-120-Q12 2.0 UEI15-120-Q48 1.8 Current limiting, hiccup autorestart See Derating Curves Storage Temperature Range ºC Thermal protection/ shutdown ºC 115 0.3 Continuous Monotonic 2 x 106 –40 to +85ºC 4.1 x 106 –55 to +125 ºC 135 6 UEI15-150-Q12 1.6 2.1 x 10 UEI15-150-Q48 1.7 2 x 106 115 cRemove overload for recovery. www.murata-ps.com Technical enquiries email: [email protected], tel: +1 508 339 3000 MDC_UEI15W.B24 Page 4 of 13 UEI15 Series Isolated Wide Input Range 15-Watt DC/DC Converters ABSOLUTE MAXIMUM RATINGS Q12 models Input Voltage Q48 models Volts Max. continuous 36 VDC Volts, transient 100mS 50 VDC Volts Max. continuous 75 VDC Volts, transient 100mS 100 VDC Volts, Min. –0.3 On/Off control, referred to –VIN Volts, Max. 15 Input Reverse Polarity Protection See fuse section Output Overvoltage, Volts Max. VOUT nom. +20% Output Current, sustained short circuit Storage Temperature Current-limited, see specs Range, Min. ºC -55 Max. ºC +125 Absolute Maximum Ratings 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 is neither implied nor recommended. SPECIFICATION NOTES (1) All models are tested and specified with external capacitors listed in the table below. The external capacitors listed below are ONLY for establishing test specifications. They are required for our test fixtures and equipment. Your application may not need them. The converter is stable with no external capacitors but Murata Power Solutions strongly recommends external caps. All caps are low-ESR types. Where two or more capacitors are listed, these are connected in parallel. All caps should mount close to the DC/DC using short leads. All specifications are typical unless noted. General conditions for Specifications are +25 deg.C, VIN=nominal, VOUT=nominal, full load. Adequate airflow must be supplied for extended testing under power. (2) Input Ripple Current is tested and specified over a 5 Hz to 20 MHz bandwidth. Input filtering is CIN=33 μF, 100V tantalum, CBUS=220 μF, 100V electrolytic, LBUS=12 μH. (3) 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. All Derating curves are presented at sea level altitude. Be aware of reduced power dissipation with increasing density altitude. INPUT/OUTPUT EXTERNAL TEST CAPACITORS Model Input Capacitor Output Capacitor(s) UEI15-033-Q12 100 μF 1 μF & 10 μF UEI15-033-Q48 4.7 μF ceramic 1 μF & 10 μF UEI15-050-Q12 100 μF 1 μF & 10 μF UEI15-050-Q48 4.7 μF ceramic 1 μF & 10 μF UEI15-120-Q12 100 μF 1 μF & 10 μF UEI15-120-Q48 4.7 μF ceramic 1 μF & 10 μF UEI15-150-Q12 100 μF 1 μF & 10 μF UEI15-150-Q48 4.7 μF ceramic 1 μF & 10 μF www.murata-ps.com (4) Mean Time Before Failure is calculated using the Telcordia (Belcore) SR332 Method 1, Case 3, ground fixed conditions, Tpcboard=+25 deg.C, full load, natural air convection. (5) The On/Off Control is normally controlled by a switch. But it may also 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 or open drain transistor. (6) Output current limiting begins when the output voltage degrades approximately 2% from the selected setting. (7) The outputs are not intended to sink appreciable reverse current. This may damage the outputs. (8) Output noise may be further reduced by adding an external filter. See I/O Filtering and Noise Reduction. (9) All models are fully operational and meet published specifications, including “cold start” at –400 C. At full power, the package temperature of all on-board components must not exceed +128°C. (10) Regulation specifications describe the deviation as the line input voltage or output load current is varied from a nominal midpoint value to either extreme. (11) The output overvoltage protection is automatic recovery after fault removal. The overvoltage may occur either from internal failure or from an external forcing voltage as in a shared power system. (12) Output current limit and short circuit protection is non-latching. When the overcurrent fault is removed, the converter will immediately recover. (13) Do not exceed maximum power specifications when adjusting the output trim. (14) 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. (15) If reverse polarity is accidentally applied to the input, a body diode will become forward biased and will conduct considerable current. To ensure reverse input protection with full output load, always connect an external input fuse in series with the +VIN input. Use approximately twice the full input current rating with nominal input voltage. (16) “Hiccup” 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. (17) On model UEI15-050-Q48, if VIN <20V, output trim may only be adjusted downwards from +5.0V (more negative). CAUTION: This product is not internally fused. To comply with safety agency certifications and to avoid injury to personnel or equipment, the user must connect an external fast-blow fuse to the input terminals. See fuse information. Technical enquiries email: [email protected], tel: +1 508 339 3000 MDC_UEI15W.B24 Page 5 of 13 UEI15 Series Isolated Wide Input Range 15-Watt DC/DC Converters APPLICATION NOTES rated current. Similar conditions apply to the On to VOUT regulated specification such as external load capacitance and soft start circuitry. 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 current-limited. We recommend a time delay fuse installed in the ungrounded input supply line with a value which is approximately twice the maximum line current, calculated at the lowest input voltage. 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, i.e. IEC/EN/UL 60950-1. Input Reverse-Polarity Protection If the input voltage polarity is reversed, an internal diode will become forward biased and likely draw excessive current from the power source. If this source is not current-limited or the circuit appropriately fused, it could cause permanent damage to the converter. 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 Input Source Impedance These converters will operate to specifications without external components, assuming that the source voltage has very low impedance and reasonable input voltage regulation. Since real-world voltage sources have finite impedance, performance is improved by adding external filter components. Sometimes only a small ceramic capacitor is sufficient. Since it is difficult to totally characterize all applications, some experimentation may be needed. Note that external input capacitors must accept high speed switching currents. Because of the switching nature of DC/DC converters, the input of these converters must be driven from a source with both low AC impedance and adequate DC input regulation. Performance will degrade with increasing input inductance. Excessive input inductance may inhibit operation. The DC input regulation specifies that the input voltage, once operating, must never degrade below the Shut-Down Threshold under all load conditions. Be sure to use adequate trace sizes and mount components close to the converter. I/O Filtering, 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. External input capacitors (Cin in the figure) serve primarily as energy storage elements, minimizing line voltage variations caused by transient IR drops in the input conductors. Users should select input capacitors for bulk capacitance (at appropriate frequencies), low ESR and high RMS ripple current ratings. In the figure below, the Cbus and Lbus components simulate a typical DC voltage bus. Your specific system configuration may require additional considerations. Please note that the values of Cin, Lbus and Cbus will vary according to the specific converter model. In critical applications, output ripple and noise (also referred to as periodic and random deviations or PARD) may be reduced by adding filter elements such as multiple external capacitors. Be sure to calculate component temperature rise from reflected AC current dissipated inside capacitor ESR. TO OSCILLOSCOPE CURRENT PROBE +INPUT VIN + – + – LBUS CBUS CIN -INPUT CIN = 33μF, ESR < 700mΩ @ 100kHz CBUS = 220μF, ESR < 100mΩ @ 100kHz LBUS = 12μH Figure 2. Measuring Input Ripple Current www.murata-ps.com Technical enquiries email: [email protected], tel: +1 508 339 3000 MDC_UEI15W.B24 Page 6 of 13 UEI15 Series Isolated Wide Input Range 15-Watt DC/DC Converters In figure 3, the two copper strips simulate real-world printed circuit impedances between the power supply and its load. In order to minimize circuit errors and standardize tests between units, scope measurements should be made using BNC connectors or the probe ground should not exceed one half inch and soldered directly to the fixture. COPPER STRIP C1 C2 SCOPE RLOAD 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. Temperature Derating Curves The graphs in the next section 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 temperature and/or 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. COPPER STRIP C1 = 0.1μF CERAMIC C2 = 10μF TANTALUM LOAD 2-3 INCHES (51-76mm) FROM MODULE Figure 3 – Measuring Output Ripple and Noise (PARD) Floating Outputs Since these are isolated DC/DC converters, their outputs are “floating” with respect to their input. The essential feature of such isolation is ideal ZERO CURRENT FLOW between input and output. Real-world converters however do exhibit tiny leakage currents between input and output (see Specifications). These leakages consist of both an AC stray capacitance coupling component and a DC leakage resistance. When using the isolation feature, do not allow the isolation voltage to exceed specifications. Otherwise the converter may be damaged. Designers will normally use the negative output (-Output) as the ground return of the load circuit. You can however use the positive output (+Output) as the ground return to effectively reverse the output polarity. Minimum Output Loading Requirements These converters employ a synchronous rectifier design topology. 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. The temperature sensor is typically located adjacent to the switching controller, approximately in the center of the unit. See the Performance and Functional Specifications. www.murata-ps.com MPS 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. As a practical matter, it is quite difficult to insert an anemometer to precisely measure airflow in most applications. Sometimes it is possible to estimate the effective airflow if you thoroughly understand the enclosure geometry, entry/exit orifice areas and the fan flowrate specifications. If in doubt, contact MPS to discuss placement and measurement techniques of suggested temperature sensors. CAUTION: If you routinely or accidentally exceed these Derating guidelines, the converter may have an unplanned Over Temperature shut down. Also, these graphs are all collected at slightly above Sea Level altitude. Be sure to reduce the derating for higher density altitude. Output Overvoltage Protection This converter monitors its output voltage for an over-voltage condition using an on-board electronic comparator. The signal is optically coupled to the primary side PWM controller. If the output exceeds OVP limits, the sensing circuit will power down the unit, and the output voltage will decrease. After a time-out period, the PWM will automatically attempt to restart, causing the output voltage to ramp up to its rated value. It is not necessary to power down and reset the converter for the this automatic OVP-recovery restart. If the fault condition persists and the output voltage climbs to excessive levels, the OVP circuitry will initiate another shutdown cycle. This on/off cycling is referred to as “hiccup” mode. It safely tests full current rated output voltage without damaging the converter. Output Fusing The converter is extensively protected against current, voltage and temperature extremes. However your output application circuit may need additional protection. In the extremely unlikely event of output circuit failure, excessive voltage could be applied to your circuit. Consider using an appropriate fuse in series with the output. Technical enquiries email: [email protected], tel: +1 508 339 3000 MDC_UEI15W.B24 Page 7 of 13 UEI15 Series Isolated Wide Input Range 15-Watt DC/DC Converters Output Current Limiting As soon as the output current increases to approximately 125% to 150% of its maximum rated value, the DC/DC converter will enter a current-limiting mode. The output voltage will decrease proportionally with increases in output current, thereby maintaining a somewhat constant power output. This is commonly referred to as power 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. 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, 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 on/off cycling is called “hiccup mode”. The hiccup cycling reduces the average output current, thereby preventing excessive internal temperatures. A short circuit can be tolerated indefinitely. Trimming the Output Voltage The Trim input to the converter allows the user to adjust the output voltage over the rated trim range (please refer to the Specifications). In the trim equations and circuit diagrams that follow, trim adjustments use either a trimpot or a single fixed resistor connected between the Trim input and either the positive or negative output terminals. (On some converters, an external user-supplied precision DC voltage may also be used for trimming). Trimming resistors should have a low temperature coefficient (±100 ppm/deg.C or less) and be mounted close to the converter. Keep leads short. If the trim function is not used, leave the trim unconnected. With no trim, the converter will exhibit its specified output voltage accuracy. −INPUT ON/OFF CONTROL +INPUT +OUTPUT 7 5-22 TURNS TRIM LOAD −OUTPUT Figure 4 – Trim adjustments using a trimpot −INPUT ON/OFF CONTROL +INPUT +OUTPUT LOAD TRIM RTRIM DOWN −OUTPUT Figure 5 – Trim adjustments to decrease Output Voltage using a Fixed Resistor There are two CAUTIONs to be aware for the Trim input: CAUTION: To avoid unplanned power down cycles, do not exceed EITHER the maximum output voltage OR the maximum output power when setting the trim. Be particularly careful with a trimpot. If the output voltage is excessive, the OVP circuit may inadvertantly shut down the converter. If the maximum power is exceeded, the converter may enter current limiting. If the power is exceeded for an extended period, the converter may overheat and encounter overtemperature shut down. CAUTION: Be careful of external electrical noise. The Trim input is a senstive input to the converter’s feedback control loop. Excessive electrical noise may cause instability or oscillation. Keep external connections short to the Trim input. Use shielding if needed. −INPUT ON/OFF CONTROL +INPUT +OUTPUT TRIM LOAD R TRIM UP −OUTPUT Figure 6 – Trim adjustments to increase Output Voltage using a Fixed Resistor www.murata-ps.com Technical enquiries email: [email protected], tel: +1 508 339 3000 MDC_UEI15W.B24 Page 8 of 13 UEI15 Series Isolated Wide Input Range 15-Watt DC/DC Converters Trim Equations Trim Up Trim Down <Connect trim resistor between Trim and −VOUT> <Connect trim resistor between Trim and +VOUT> + Vcc ON/OFF CONTROL CONTROL UEI15-033-Q12, Q48 RTUP (:) = 12775 VO – 3.3 – 2050 RTDOWN (:) = 5110 (Vo - 2.5) 3.3 – VO – 2050 -INPUT UEI15-050-Q12, Q48 RTUP (:) = 12775 VO – 5 – 2050 RTDOWN (:) = 5110 (Vo - 2.5) 5 – VO – 2050 Figure 7 – Driving the On/Off Control Pin (suggested circuit) UEI15-120-Q12, Q48 RTUP (:) = 25000 VO – 12 – 5110 RTDOWN (:) = 10000 (Vo-2.5) 12 – VO – 5110 UEI15-150-Q12, Q48 RTUP (:) = 25000 VO – 15 – 5110 RTDOWN (:) = 10000 (Vo-2.5) 15 – VO – 5110 Where Vo = Desired output voltage. Adjustment accuracy is subject to resistor tolerances and factory-adjusted output accuracy. Mount trim resistor close to converter. Use short leads. Remote On/Off Control On the input side, a remote On/Off Control can be ordered with either polarity. Positive: Standard models are enabled when the On/Off pin is left open or is pulled high to +VIN with respect to –VIN. An internal bias current causes the open pin to rise to +VIN. Some models will also turn on at lower intermediate voltages (see Specifications). Positive-polarity devices are disabled when the On/Off is grounded or brought to within a low voltage (see Specifications) with respect to –VIN. Negative: Optional negative-polarity devices are on (enabled) when the On/ Off is grounded or brought to within a low voltage (see Specifications) with respect to –VIN. The device is off (disabled) when the On/Off is left open or is pulled high to +15VDC max. with respect to –VIN. There are three CAUTIONs for the On/Off Control: CAUTION: To retain full output circuit isolation, control the On/Off from the input side ONLY. If you must control it from circuits in the output, use some form of optoisolation to the On/Off Control. This latter condition is unlikely because the device controlling the On/Off would have to remain powered on and not be powered from the converter. CAUTION: While it is possible to control the On/Off with external logic if you carefully observe the voltage levels, the preferred circuit is either an open drain/open collector transistor, a switch or a relay (which can thereupon be controlled by logic). The On/Off prefers to be set at +VIN (open pin) for the ON state, assuming positive logic. CAUTION: Do not apply voltages to the On/Off pin when there is no input power voltage. Otherwise the converter may be permanently damaged. 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. Be cautious when there is high atmospheric humidity. We strongly recommend a mild pre-bake (100° C. for 30 minutes). Your production environment may differ; therefore please thoroughly review these guidelines with your process engineers. Wave Solder Operations for through-hole mounted products (THMT) For Sn/Ag/Cu based solders: Dynamic control of the On/Off function should be able to sink appropriate signal current when brought low and withstand appropriate voltage when brought high. Be aware too that there is a finite time in milliseconds (see Specifications) between the time of On/Off Control activation and stable, regulated output. This time will vary slightly with output load type and current and input conditions. www.murata-ps.com Maximum Preheat Temperature 115° C. Maximum Pot Temperature 270° C. Maximum Solder Dwell Time 7 seconds For Sn/Pb based solders: Maximum Preheat Temperature 105° C. Maximum Pot Temperature 250° C. Maximum Solder Dwell Time 6 seconds Technical enquiries email: [email protected], tel: +1 508 339 3000 MDC_UEI15W.B24 Page 9 of 13 UEI15 Series Isolated Wide Input Range 15-Watt DC/DC Converters PERFORMANCE DATA UEI15-033-Q12 Efficiency vs. Line Voltage and Load Current @ 25°C Maximum Current Temperature Derating @sea level (VIN = 12V or 24V, airflow from input to output) 90 5.5 85 5.0 80 4.5 Efficiency (%) Output Current (A ( mps) Vin = 36 V 75 Vin = 24 V 70 Vin = 18 V Vin = 9 V 65 60 Natural a Convection 4.0 3.5 3.0 2.5 55 50 2.0 0 0.5 1 1.5 2 2.5 3 3.5 4 40 45 50 55 60 65 70 75 80 85 80 85 A bient temperature (°C) Am Load Current (Amps) UEI15-033-Q48 Efficiency vs. Line Voltage and Load Current @ 25°C Maximum Current Temperature Derating @sea level (VIN = 24V, airflow from input to output) 90 5.10 85 4.90 Output Current (Amps) 75 Vin = 75 V 70 Vin = 48 V Vin = 18 V 65 4.50 4.30 4.10 3.90 60 3.70 55 3.50 40 45 50 55 60 65 70 75 A bient Temperature (°C) Am 50 1 2 3 4 5 Load Current (Amps) UEI15-033-Q48 Maximum Current Temperature Derating @sea level (VIN = 48V, airflow from input to output) 5.20 5.00 Output Current (A ( mps) Efficiency (%) Natural a Convection 100 LFM 200 LFM 300 LFM 4.70 80 Natural a Convection 100 LFM 200 LFM 300 LFM 400 LFM 4.80 4.60 4.40 4.20 4.00 3.80 40 45 50 55 60 65 70 75 80 85 A bient temperature (°C) Am www.murata-ps.com Technical enquiries email: [email protected], tel: +1 508 339 3000 MDC_UEI15W.B24 Page 10 of 13 UEI15 Series Isolated Wide Input Range 15-Watt DC/DC Converters PERFORMANCE DATA UEI15-050-Q12 Efficiency vs. Line Voltage and Load Current @ 25°C Maximum Current Temperature Derating @sea level (VIN = 12 or 24V, airflow from input to output) 100 3.2 90 3.0 80 Output Current (A ( mps) Vin = 36 V 60 Vin = 24 V 50 Vin = 18 V 40 Vin = 9 V 30 20 2.8 2.6 2.4 2.2 10 0.25 0.5 0.75 1 1.25 1.5 1.75 2 2.25 2.5 2.75 3 2.0 40 Load Current (Amps) 45 50 55 60 65 70 75 80 85 A bient temperature (°C) Am UEI15-050-Q48 Maximum Current Temperature Derating @Sea Level (VIN = 24V or 48V, airflow is from input to output) Efficiency vs. Line Voltage and Load Current @ 25°C 100 90 80 70 60 50 40 30 20 10 0 3.20 Output Current (Amps) Efficiency (%) 3.10 Vin = 75 V Vin = 36 V Vin = 24 V Vin = 18 V 3.00 Natural Convection 2.90 2.80 2.70 2.60 2.50 40 0 0.5 1 1.5 2 2.5 45 50 3 55 60 65 70 75 80 85 80 85 Ambient Temperature (°C) Load Current (Amps) UEI15-120-Q12 Efficiency vs. Line Voltage and Load Current @ 25°C Maximum Current Temperature Derating @Sea Level (VIN = 12V or 24V, airflow is from pin 2 to pin 1) 90 1.30 85 1.20 80 75 70 65 Vin = 36 V Vin = 24 V Vin = 18 V Vin = 9 V Output Current (Amps) Efficiency (%) Efficiency (%) Natural a Convection 70 Natural Convection 1.10 1.00 0.90 0.80 0.70 0.60 0.50 60 40 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 45 50 55 60 65 70 75 Ambient Temperature (°C) Load Current (Amps) www.murata-ps.com Technical enquiries email: [email protected], tel: +1 508 339 3000 MDC_UEI15W.B24 Page 11 of 13 UEI15 Series Isolated Wide Input Range 15-Watt DC/DC Converters PERFORMANCE DATA UEI15-120-Q48 Efficiency vs. Line Voltage and Load Current @ 25°C Maximum Current Temperature Derating @Sea Level (VIN = 24V or 48V, airflow is from pin 2 to pin 1) 90 88 1.3 86 Vin = 75 V Vin = 48 V Vin = 24 V Vin = 18 V 82 80 1.1 Output Current (Amps) Efficiency (%) Natural Convection 1.2 84 78 76 1.0 0.9 0.8 0.7 0.6 74 0.5 72 40 45 50 70 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 55 60 65 70 75 80 85 Ambient Temperature (°C) 1.3 Load Current (Amps) UEI15-150-Q12 Efficiency vs. Line Voltage and Load Current @ 25°C Maximum Current Temperature Derating @Sea Level (VIN = 12V and 24V, airflow is from input to output) 90 1.15 86 1.10 Output Current (Amps) 88 Efficiency (%) 84 82 Vin = 36 V Vin = 24 V Vin = 9 V 80 78 76 Natural Convection 1.05 1.00 0.95 0.90 0.85 74 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 0.80 1.1 40 45 50 Load Current (Amps) 55 60 65 70 75 80 85 80 85 Ambient Temperature (°C) UEI15-150-Q48 Efficiency vs. Line Voltage and Load Current @ 25°C Maximum Current Temperature Derating @Sea Level (VIN = 24V and 48V, airflow is from input to output) 95 1.15 90 Output Current (Amps) 1.10 Efficiency (%) 85 80 75 Vin = 75 V Vin = 48 V Vin = 24 V Vin = 18 V 70 65 Natural Convection 1.05 1.00 0.95 0.90 0.85 60 0.80 0.07 0.18 0.28 0.38 0.49 0.59 0.69 0.80 0.90 1.00 1.10 Load Current (Amps) 40 45 50 55 60 65 70 75 Ambient Temperature (°C) www.murata-ps.com Technical enquiries email: [email protected], tel: +1 508 339 3000 MDC_UEI15W.B24 Page 12 of 13 UEI15 Series Isolated Wide Input Range 15-Watt DC/DC Converters Murata Power Solutions, Inc. 11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A. Tel: (508) 339-3000 (800) 233-2765 Fax: (508) 339-6356 www.murata-ps.com email: [email protected] ISO 9001 and 14001 REGISTERED 03/30/09 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. © 2009 Murata Power Solutions, Inc. www.murata-ps.com USA: Mansfield (MA), Tel: (508) 339-3000, email: [email protected] Canada: Toronto, Tel: (866) 740-1232, email: [email protected] UK: Milton Keynes, Tel: +44 (0)1908 615232, email: [email protected] France: Montigny Le Bretonneux, Tel: +33 (0)1 34 60 01 01, email: [email protected] Germany: München, Tel: +49 (0)89-544334-0, email: [email protected] Japan: Tokyo, Tel: 3-3779-1031, email: [email protected] Osaka, Tel: 6-6354-2025, email: [email protected] China: Shanghai, Tel: +86 215 027 3678, email: [email protected] Guangzhou, Tel: +86 208 221 8066, email: [email protected] Singapore: Parkway Centre, Tel: +65 6348 9096, email: [email protected] Technical enquiries email: [email protected], tel: +1 508 339 3000 MDC_UEI15W.B24 Page 13 of 13