Q48SC12025 300W DC/DC Power Modules FEATURES Input voltage range: 36V~75V Output voltage range ( trim and PMBUS) 8V~13.2V Fully regulated from 36 to 75Vin High efficiency : 95.1% @ 48Vin/25A Size: 58.4mm x 36.8mm x 11.2mm (2.3” x 1.45” x 0.44”) (without heat-spreader) 58.4mm x 36.8mm x 12.7mm (2.3” x 1.45” x 0.5”) (with heat-spreader) Industry standard DOSA compliant pin out Fully protected: Input UVLO, Output OCP and OVP, OTP Delphi Series Q48SC12025, Quarter Brick Family DC/DC Power Modules: 36~75Vin, 12Vout, 300W Droop current sharing 1500V isolation No minimum load required Fixed frequency operation ISO 9001, TL 9000, ISO 14001, QS9000, OHSAS18001 certified manufacturing facility UL/CUL 60950-1 (US & Canada) OPTIONS The Delphi series Q48SC12025, quarter brick, 36~75V input, Positive or Negative On/Off single output 12V, are full digital control DC/DC converter, and are Droop current sharing the latest offering from a world leader in power system and Digital pins technology and manufacturing ― Delta Electronics, Inc. This Heat spreader logic product provides up to 300 watts of power at 36~75V input in an industry standard, DOSA compliant footprint and pin out. The Q48SC12025 offers more than 95.1% high efficiency at 48V input, 12V output and 25A load. There is a built-in digital PWM controller in the Q48SC12025 series, which is used to complete the Vo feedback, PWM signal generation, droop or active current sharing, fault protection, output voltage trim, on/off control and PMBUS communications, and so on. With the digital control, many design and application flexibility, advanced performance, and reliability are obtained. The Q48SC12025 can be connected in parallel APPLICATIONS Datacom / Networking Wireless networks Optical network equipment Server and data storage Industrial / Test equipment directly for higher power without adding external oring-fet. Datasheet DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P1 TECHNICAL SPECIFICATIONS (TA=25°C, airflow rate=400 LFM, Vin=48Vdc, nominal Vout unless otherwise noted.) PARAMETER NOTES and CONDITIONS Q48SC12025 Min. ABSOLUTE MAXIMUM RATINGS Input Voltage Continuous Transient (100ms) On/off Pin Voltage Other Pin Voltage Output negative voltage Operating ambient Temperature Storage Temperature Input/Output Isolation Voltage INPUT CHARACTERISTICS Operating Input Voltage Input Under-Voltage Lockout Turn-On Voltage Threshold (Adjustable via PMBus, VIN_ON) Turn-Off Voltage Threshold (Adjustable via PMBus, VIN_OFF) Lockout Hysteresis Voltage Maximum Input Current No-Load Input Current Off Converter Input Current Input Capacitance Inrush Current (I2t) Input Reflected-Ripple Current Input Voltage Ripple Rejection OUTPUT CHARACTERISTICS The module without droop current sharing option code Output Voltage Set Point (Adjustable via PMBus) Output Voltage Regulation Over Line Over Load Over tempearture The module with droop current sharing option code Output Voltage Set Point (Adjustable via PMBus) Output Voltage Regulation Over Line Over Load Over tempearture Both with and without droop current sharing option code Output Voltage Trim and PMBUS Range Output Voltage Remote Sense Range (note 2) Output Over-Voltage Lockout (Adjustable via PMBus, VOUT_OV_FAULT_LIMIT) Operating Output Current Range Output DC Current-Limit Inception Output Capacitance Output Voltage Ripple and Noise Peak-to-Peak RMS Typ. 0 100ms Trim/Current Sharing, C2, Data, SMBAlert, Clock, Addr1, Addr0 -50 -0.3 -40 -55 36 48 34 31 Max. Units 75 100 50 3.6 0.3 85 125 1500 Vdc Vdc V V V °C °C Vdc 75 Vdc 36 Vdc 34 Vdc 2 Vin=36V, 100% Load Vin=48V Vin=48V 80 10 100 110 18 11 140 26 1 P-P thru 12µH inductor, 5Hz to 20MHz 120Hz Vin=48V, Io=0A , Ta=25°C 50 50 11.88 12 Vin=36V to 75V, Io=100% load Vin=36V to 75V, Io=Io,min to Io,max Vin=36V to 75V, Io=100% load, Ta= -40C to 85C Vin=48V, Io=0A , Ta=25°C 12.28 12.4 Vin=36V to 75V, Io=100% load Vin=36V to 75V, Io=Io,min to Io,max Vin=36V to 75V, Io=100% load, Ta= -40C to 85C -650 -550 Vin=36V to 75V, Pout ≦ max rated power,Io ≦ Io.max Vin=36V to 75V, Pout ≦ max rated power,Io ≦ Io.max -33.3 5.8 12.12 Vdc ±40 ±40 mV mV mV 12.52 Vdc ±40 mV mV mV 10 10 % % 15.2 Full input voltage range 0 115 300 Vin=48V, Full load, 20MHz bandwidth Co= 300uF/16V (polymer ) + 10u/16V (Tantalum Capacitor) +1u/16V (Ceramic ) Co= 300uF/16V (polymer ) + 10u/16V (Tantalum Capacitor) +1u/16V (Ceramic ) Vdc A mA mA uF A2S mA dB Vdc 25 135 15000 A % µF 75 110 mV 22 32 mV 350 -350 500 500 mV mV µs DYNAMIC CHARACTERISTICS Output Voltage Current Transient Positive Step Change in Output Current Negative Step Change in Output Current Settling Time (within 1% Vout nominal) Turn-On Transient (Adjustable via PMBus) Start-Up Time, From On/Off Control Start-Up Time, From Input Output voltage Rise Time EFFICIENCY 100% Load 60% Load ISOLATION CHARACTERISTICS Input to Output Isolation Resistance Isolation Capacitance Datasheet DS_Q48SC12025_06022015 Vin=48V, Load Slew rate 0.1A/µs with a 1uF ceramic , a 10uF tantalum, and a 300uF polymer capacitor 50% Io.max to 75% Io.max 75% Io.max to 50% Io.max -500 From On/off to 90%Vo final value From Input to 90%Vo final value From 10%Vo final value to 90%Vo final value 55 75 30 ms ms ms Vin=48V Vin=48V 95.1 95.6 % % 1500 10 6800 Vdc MΩ pF E-mail: [email protected] http://www.deltaww.com/dcdc P2 TECHNICAL SPECIFICATIONS (TA=25°C, airflow rate=400 LFM, Vin=48Vdc, nominal Vout unless otherwise noted.) PARAMETER NOTES and CONDITIONS Q48SC12025 Min. FEATURE CHARACTERISTICS Switching Frequency ON/OFF Control, Positive Remote On/Off logic Logic Low (Module On) Logic High (Module Off) ON/OFF Current (for both remote on/off logic) GENERAL SPECIFICATIONS MTBF Weight(without heat spreader) Weight(with heat spreader) Typ. Max. 130 Von/off at Ion/off=1.0mA Von/off at Ion/off=0.0 µA Ion/off at Von/off=0.0V -0.7 3.5 Io=80% of Io max; Ta=25°C; Airflow=300LFM Units KHz 0.8 50 0.5 4.5 50 65 V V mA M grams grams Refer to Figure 22 for Hot spot 1 location 126 °C (48Vin,80% Io, 200LFM,Airflow from Vin+ to Vin-) Refer to Figure 24 for Hot spot 2 location Over-Temperature Shutdown (With heat spreader) 114 °C (48Vin,80% Io, 200LFM,Airflow from Vin+ to Vin-) Over-Temperature Shutdown ( NTC resistor ) Refer to Figure 22 for NTC resistor location 125 °C Note1: Please attach thermocouple on NTC resistor to test OTP function, the hot spots’ temperature is just for reference. And the OTP is Adjustable via PMBus. Note2: Output voltage range 5.8% for remote sense-; Output voltage range 10% for remote sense+. Over-Temperature Shutdown ( Without heat spreader) DIGITAL INTERFACE SPECIFICATIONS (TA=25°C, airflow rate=400 LFM, Vin=48Vdc, nominal Vout unless otherwise noted.) PARAMETER NOTES and CONDITIONS Q48SC12025 Min. PMBUS SIGNAL INTERFACE CHARACTERISTICS Input High Voltage (CLK, DATA) Input Low Voltage (CLK, DATA) Input high level current (CLK, DATA) Input low level current (CLK, DATA) Output Low Voltage (SMBALERT#) Output high level open drain leakage current (SMBALERT#) PMBus Operating frequency range Typ. 2.1 0 -10 -10 IOUT=2mA VOUT=3.6V 0 Max. Units 3.3 0.8 10 10 0.4 Vdc Vdc uA uA Vdc 10 100 or 400 uA kHz Measurement System Characteristics 12.5A<IOUT<25A 1A<IOUT<12.5A Output current reading accuracy -5 -1.7 VOUT reading accuracy VIN reading accuracy Temperature sense range Temperature reading accuracy 1.4 3 2.5 1 -2 0 -5 +2 +5 % A % Vdc °C °C PIN DEFINATION Pin# Name 1 VIN(+) 2 ON/OFF 3 VIN(-) 4 VOUT(-) 5 SENSE(-) 6 TRIM 7 SENSE(+) 8 VOUT(+) Function Pin# Name Function 9 C2 PGOOD pin, and this pin also could be configurated as secondary on/off control pin 10 SIG_GND Signal ground 11 DATA PMBus data line 12 SMBALERT PMBus SMBAlert line Remote sense 13 CLOCK PMBus clock line Trim note 3 14 ADDR1 ADDR1 pin sets the high order digit of the address. Remote sense 15 ADDR0 ADDR0 pin sets the low order digit of the address. Primary on/off control pin Note3: see the page 27. Datasheet DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P3 SIMPLIFIED APPLICATION CIRCUIT Delta DC/DC Module ADDR0 ADDR1 VOUT(+) VIN(+) Fuse Resistance of trace SENSE(+) EMI filter Input source ON/OFF TRIM CASE VIn(-) Reverse voltage protect CLOCK Load SENSE(-) VOUT(-) SMB-ALERT C2 DATA Resistance of trace On/off control CLK DATA ALERT PGOOD / ON/OFF System MCU Datasheet DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P4 ELECTRICAL CHARACTERISTICS CURVES 98 22 96 20 94 75V 18 75V 48V 36V POWER DISSIPATION (W) EFFICIENCY(%) 92 90 88 86 16 48V 14 12 36V 10 8 84 6 82 4 80 2 3 6 9 12 15 18 21 24 3 6 9 12 15 18 21 24 OUTPUT CURRENT(A) OUTPUT CURRENT (A) Figure 1: Efficiency vs. load current for minimum, nominal, and maximum input voltage at 25°C. Figure 2: Power loss vs. load current for minimum, nominal, and maximum input voltage at 25°C. 10 INPUT CURRENT(A) 8 6 4 2 0 25 30 35 40 45 50 55 60 65 70 75 INPUT VOLTAGE(V) Figure 3: Typical full load input characteristics at room temperature. Datasheet DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P5 ELECTRICAL CHARACTERISTICS CURVES For Negative Remote ON/OFF Logic Figure 4: Turn-on transient at zero load current) (20ms/div). Top Trace: Vout; 5V/div; Bottom Trace: ON/OFF input: 5V/div. Figure 5: Turn-on transient at full rated load current (20ms/div). Top Trace: Vout:5V/div; Bottom Trace: ON/OFF input:5V/div. For Input Voltage Start up Figure 6: Turn-on transient at zero load current (100 ms/div). Top Trace: Vout; 5V/div; Bottom Trace: input voltage: 30V/div. Datasheet DS_Q48SC12025_06022015 Figure 7: Turn-on transient at full rated load current (100 ms/div). Top Trace: Vout; 5V/div; Bottom Trace: input voltage: 30V/div. E-mail: [email protected] http://www.deltaww.com/dcdc P6 ELECTRICAL CHARACTERISTICS CURVES Figure 8: Output voltage response to step-change in load current (75%-50% of Io, max; di/dt = 0.1A/µs, Vin=48V). Load cap:300µF, electrolytic capacitor ; 10µF, tantalum capacitor and 1µF ceramic capacitor. Top Trace: Vout (200mV/div, 200us/div); Bottom Trace: Io (10A/div, 200us/div). Scope measurement should be made using a BNC cable (length shorter than 20 inches). Position the load between 51 mm to 76 mm (2 inches to 3 inches) from the module.. Figure 9: Output voltage response to step-change in load current (50%-75% of Io, max; di/dt = 0.1A/µs, Vin=48V). Load cap: 300µF, electrolytic capacitor ;10µF, tantalum capacitor and 1µF ceramic capacitor. Top Trace: Vout (200mV/div, 200us/div); Bottom Trace: Io (10A/div, 200us/div). Scope measurement should be made using a BNC cable (length shorter than 20 inches). Position the load between 51 mm to 76 mm (2 inches to 3 inches) from the module.. Figure 10: Test set-up diagram showing measurement points for Input Terminal Ripple Current and Input Reflected Ripple Current. Note: Measured input reflected-ripple current with a simulated source Inductance (LTEST) of 12 μH. Capacitor Cs offset possible battery impedance. Measure current as shown above. Figure 11: Input Terminal Ripple Current, ic, at full rated output current and nominal input voltage with 12µH source impedance and 100µF electrolytic capacitor (1A/div，2us/div). Datasheet DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P7 ELECTRICAL CHARACTERISTICS CURVES Figure 12: Input reflected ripple current, is, through a 12µH source inductor at nominal input voltage and rated load current (20mA/div，2us/div). Figure 13: Output voltage noise and ripple measurement test setup. 13 OUTPUT VOLTAGE(V) 12.5 12 11.5 11 10.5 10 0 5 10 15 20 25 30 35 OUTPUT CURRENT(A) Without droop Figure 14: Output voltage ripple at nominal input voltage and rated load current (Io=25A)(50 mV/div, 2us/div) Loadcapacitance:300uF(Electrolytic)+10uF(Tantalum)+1uF(Ce ramic) and min Co. Bandwidth: 20 MHz. Datasheet DS_Q48SC12025_06022015 With droop Figure 15: Output voltage vs. load current showing typical current limit curves and converter shutdown points. E-mail: [email protected] http://www.deltaww.com/dcdc P8 Safety Considerations DESIGN CONSIDERATIONS Input Source Impedance The impedance of the input source connecting to the DC/DC power modules will interact with the modules and affect the stability. A low ac-impedance input source is recommended. If the source inductance is more than a few μH, we advise adding a 100μF electrolytic capacitor (ESR < 0.2 Ω at 100 kHz) mounted close to the input of the module to improve the stability. Layout and EMC Considerations Delta’s DC/DC power modules are designed to operate in a wide variety of systems and applications. For design assistance with EMC compliance and related PWB layout issues, please contact Delta’s technical support team. An external input filter module is available for easier EMC compliance design. Below is the reference design for an input filter and tested result which can meet class B in CISSPR 22. Schematic: The power module must be installed in compliance with the spacing and separation requirements of the end-user’s safety agency standard, i.e., UL60950-1, CSA C22.2 NO. 60950-1 2nd, IEC 60950-1 2nd : 2005,EN 60950-1 2nd: 2006+A11+A1: 2010, if the system in which the power module is to be used must meet safety agency requirements. When the input source is SELV, the power module meets SELV (safety extra-low voltage) requirements. If the input source is a hazardous voltage which is greater than 60 Vdc and less than or equal to 75 Vdc, for the module’s output to meet SELV requirements, all of the following must be met: The input source must be insulated from the ac mains by reinforced or double insulation. The input terminals of the module are not operator accessible. One Vout pin is grounded. A SELV reliability test is conducted on the system where the module is used, in combination with the module, to ensure hazardous voltage does not appear at the module’s output. When installed into a Class II equipment (without grounding), spacing consideration should be given to the end-use installation, as the spacing between the module and mounting surface have not been evaluated. The power module has extra-low voltage (ELV) outputs when all inputs are ELV. Test result: dBμV 80.0 Limits 55022MQP 55022MAV 70.0 60.0 50.0 40.0 Transducer 8130 Traces PK+ AV 30.0 20.0 10.0 0.0 150 kHz 1 MHz 10 MHz 30 MHz 25C, 48Vin, full load, Green line is average peak mode and blue line is quasi mode. Datasheet DS_Q48SC12025_06022015 This power module is not internally fused. To achieve optimum safety and system protection, an input line fuse is highly recommended. The safety agencies require a normal-blow fuse with 50A maximum rating to be installed in the ungrounded lead. A lower rated fuse can be used based on the maximum inrush transient energy and maximum input current. Soldering and Cleaning Considerations Post solder cleaning is usually the final board assembly process before the board or system undergoes electrical testing. Inadequate cleaning and/or drying may lower the reliability of a power module and severely affect the finished circuit board assembly test. Adequate cleaning and/or drying is especially important for un-encapsulated and/or open frame type power modules. For assistance on appropriate soldering and cleaning procedures, please contact Delta’s technical support team. E-mail: [email protected] http://www.deltaww.com/dcdc P9 FEATURES DESCRIPTIONS Over-Power Protection The modules include an internal output over-power protection circuit, which will endure power limiting for an unlimited duration during output overload. If the output current exceeds the OCP set points, the modules will automatically shut down (hiccup mode). The modules will try to restart after shutdown. If the overload condition still exists, the modules will shut down again. This restart trial will continue until the overload condition is corrected. The OCP function could be changed via PMBUS. The commond related to OCP function are IOUT_OC_WARN_LIMIT, IOUT_OC_FAULT_LIMIT and IOUT_OC_ FAULT _RESPONSE. Over-Temperature Protection The over-temperature protection consists of circuitry that provides protection from thermal damage. If the temperature exceeds the over-temperature threshold, the modules will shut down, and enter the auto-restart mode. For auto-restart mode, the module will monitor the module temperature after shutdown. Once the temperature of module is decreased by an OTP hysteresis, the module will restart. Output Overvoltage Protection The module can detect and respond to output overvoltage conditions. If the overvoltage condition causes the output voltage to rise above the limit in the Specifications Table, the module will shut down. The modules will try to restart after shutdown. If fault condition still exists, the modules will shut down again. This restart trial will continue until the fault condition is corrected. The Vo OVP function could be changed via PMBUS. The commond related to Vo OVP function are VOUT_OV_WARN_LIMIT, VOUT_OV_FAULT_LIMIT and VOUT_OV_ FAULT _RESPONSE. Input Over Voltage Lockout The module can detect and respond to input overvoltage conditions. If the input voltage rises above the limit in the Specifications Table, the module will shut down. The module is factory default configured for auto-restart operation. The auto-restart feature continually monitors the input voltage and will restart the module when the level falls 6V below the Input OVP level. The Vin OVP function could be changed via PMBUS. The commond related to Vin OVP function are VIN_OV_FAULT_LIMIT and VIN_OV_FAULT_RESPONSE The OTP function could be changed via PMBUS. The commond related to OTP function are OT _WARN_LIMIT, OT_FAULT_LIMIT and OT_FAULT _RESPONSE. Remote ON/OFF (ENABLE) Input Under Voltage Lockout The remote ON/OFF (ENABLE) feature on the module is negative logic. The low logic turns the modules on. And the high logic, or floating, turns the modules off. When Vin exceeds Vin turn on threshold, the module output is enabled, when Vin falls below Vin turn off threshold, the module output is disabled. Vin turn on threshold and Vin turn off threshold can be reconfigured via the PMBus interface. Remote ON/OFF (ENABLE) can be controlled by an external switch between the on/off terminal and the Vin(-) terminal. The switch can be an open collector or open drain. The Vin UVP function could be changed via PMBUS. The commond related to Vin UVP function are VIN_ON and VIN_OFF. Datasheet DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P10 For the negative logic, if the remote ON/OFF (ENABLE) feature is not used, please maintain the ENABLE pin to Vin(-). Vin+ Resistance of trace Vin(+) Vout(+) Sense(+) Input source Vo+ Load Sense(-) Vin(-) Vout(-) Resistance of trace ENABLE R load Vin- Vo- Figure 16: Remote ON/OFF (ENABLE) implementation Secondary Remote On/Off Reference to the Vo(-) terminal, there is a C2 pin. The default configuration is set to PGOOD function. And such pin can be reconfigured as secondary remote on/off pin by the PMBus interface including either negative or positive logic. Negative logic turns the module on during a logic low and off during a logic high. Positive logic turns the modules on during a logic high and off during a logic low. The secondary remote on/off can be controlled by an external switch between the on/off terminal and the Vo(-) terminal. The switch can be an open collector or open drain. MFR_C1_C2_ARA_CONFIG, MFR_ C2_LOGIC, MFR_PGOOD_POLARITY are used to config C2 pin function. Figure 17: Circuit Configuration for remote sense. Configurable Control Pins The module contains one configurable control pins C2, referenced to the module secondary SIG_GND. See Mechanical Views for pin locations. The following table list the default factory configurations for the functions assigned to the pin. Pin Designation/Function C2 Configuration Power Good On/Off Factory Default Optional Vias PMBUS Output Voltage Adjustment (TRIM) note1 To increase or decrease the output voltage set point, connect an external resistor between the TRIM pin and either the Vo(+) or Vo(-). The TRIM pin should be left open if this feature is not used. Remote Sense Remote sense minimizes the effects of distribution losses by regulating the voltage at the remote-sense connections (See Figure 17). The SENSE(-) pin should be always connected to VO(-) pin. The voltage between the remote-sense pins and the output terminals must not exceed the output voltage sense range given in the Feature Specifications [VO(+) – VO(–)] – SENSE(+) ≤0.5 V The output voltage can also be increased by the trim, the maximum increase for the output voltage is the sum of both. The amount of power delivered by the module is defined as the voltage at the output terminals multiplied by the output current. When using remote sense and trim, the output voltage of the module can be increased, which at the same output current, would increase the power output of the module. Care should be taken to ensure that the maximum output power of the module remains at or below the maximum rated power (Maximum rated power = Vo,set x Io,max) Datasheet DS_Q48SC12025_06022015 Figure 18: Circuit configuration for trim-down (decrease output voltage) If the external resistor is connected between the TRIM and Vo (-) pins, the output voltage set point decreases (Fig. 18). The external resistor value required to obtain a percentage of output voltage change △% is defined as: 511 Rtrim _ down 10.2K Ex. When Trim-down -10% (12V×0.9=10.8V) 511 Rtrim _ down 10.2K 40.9K 10 E-mail: [email protected] http://www.deltaww.com/dcdc P11 pin of the parallel module together, the current sharing can be realized automatically. Vin+ Vin+ On/off On/off Vin Figure 19: Circuit configuration for trim-up (increase output voltage) If the external resistor is connected between the TRIM and Vo (+) the output voltage set point increases (Fig.19) The external resistor value required to obtain a percentage output voltage change △% is defined as: 5.11Vo (100 ) 511 Rtrim _ up 10.2K 1.225 Vo+ Vo+ Module I V i nVin- Vo- Vin+ Vin+ Vo+ On/off V i nVin- Load Module II Vo- Figure 20: Parallel and droop current sharing configuration for no redundancy requirement system If system has no redundancy requirement, the module can be parallel directly for higher power without adding external oring-fet; whereas, If the redundancy function is required, the external oring-fet should be added. Ex. When Trim-up +10% (12V×1.1=13.2V) Rtrim _ up 5.11 12 (100 10) 511 10.2 489.3K 1.225 10 10 Care should be taken to ensure that the maximum output power of the module remains at or below the maximum rated power. Note1: see the last page. Power Good, PG The module provides a Power Good (PG) signal which is provided by the IC inside module, voltage level 3.3V, to indicate that the output voltage is within the normal output voltage range of the power module. The PG signal will be de-asserted to a low state if any condition such as overtemperature, overcurrent or loss of regulation occurs that would result in the output voltage going below the normal voltage range value. The Vin PG function could be changed via PMBUS. The commond related to Vin OVP function are POWER_GOOD_ON and POWER_GOOD_OFF. Parallel and Droop Current Sharing The modules are capable of operating in parallel, and realizing current sharing by droop current sharing method. There is about 400mV output voltage droop from 0A to full output Load, and there is no current sharing pin. By connectting the Vin pin and the Vo DS_Q48SC12025_06022015 For a normal parallel operation the following precautions must be observed: 1. The current sharing accuracy equation is: X% = | Io – ( Itotal / N ) | / Irated, Where, Io is the output current of per module; Itotal is the total load current; N is parallel module numbers; Irated is the rated full load current of per module. 2. To ensure a better steady current sharing accuracy, below design guideline should be followed: a) The inputs of the converters must be connected to the same voltage source; and the PCB trace resistance from Input voltage source to Vin+ and Vin- of each converter should be equalized as much as possible. b) The PCB trace resistance from each converter’s output to the load should be equalized as much as possible. c) For accurate current sharing accuracy test, the module should be soldered in order to avoid the unbalance of the touch resistance between the modules to the test board. 3. To ensure the parallel module can start up monotonically without trigging the OCP circuit, below design guideline should be followed: a) Before all the parallel module finished start up, the total load current should be lower than the rated current of 1 module. b) The ON/OFF pin of the converters should be connected together to keep the parallel modules start up at the same time. c) The under voltage lockout point will slightly vary from unit to unit. The dv/dt of the rising edge of the input source voltage must be greater than 1V/ms to ensure that the parallel module start up at the same time. E-mail: [email protected] http://www.deltaww.com/dcdc P12 THERMAL CONSIDERATIONS Thermal management is an important part of the system design. To ensure proper, reliable operation, sufficient cooling of the power module is needed over the entire temperature range of the module. Convection cooling is usually the dominant mode of heat transfer. Hence, the choice of equipment to characterize the thermal performance of the power module is a wind tunnel. Thermal Testing Setup Delta’s DC/DC power modules are characterized in heated vertical wind tunnels that simulate the thermal environments encountered in most electronics equipment. This type of equipment commonly uses vertically mounted circuit cards in cabinet racks in which the power modules are mounted. The following figure shows the wind tunnel characterization setup. The power module is mounted on a 185mmX185mm,70μm (2Oz),6 layers test PWB and is vertically positioned within the wind tunnel. The space between the neighboring PWB and the top of the power module is constantly kept at 6.35mm (0.25’’). PWB FANCING PWB MODULE 50.8(2.00") AIR VELOCITY AND AMBIENT TEMPERATURE SURED BELOW THE MODULE AIR FLOW Note: Wind Tunnel Test Setup Figure Dimensions are in millimeters and (Inches) Figure 21: Wind tunnel test setup Thermal Derating Heat can be removed by increasing airflow over the module. To enhance system reliability, the power module should always be operated below the maximum operating temperature. If the temperature exceeds the maximum module temperature, reliability of the unit may be affected. DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P13 THERMAL CURVES THERMAL CURVES (WITHOUT HEAT SPREADER) (WITH HEAT SPREADER) AIRFLOW AIRFLOW HOT SPOT 2 HOT SPOT 1 NTC RESISTOR Figure 22: * Hot spot 1& NTC resistor temperature measured points. The allowed maximum hot spot 1 temperature is defined at 112℃ Figure 24: * Hot spot 2 temperature measured point. The allowed maximum hot spot 2 temperature is defined at 102℃ Q48SC12025(Standard) Output Current vs. Ambient Temperature and Air Velocity @Vin = 48V (Transverse Orientation) Q48SC12025(Standard) Output Current vs. Ambient Temperature and Air Velocity @Vin = 48V (Transverse Orientation,with Heat Spreader) Output Current (A) Output Current (A) 25 25 Natural Convection 20 Natural Convection 20 100LFM 100LFM 15 15 200LFM 200LFM 300LFM 10 10 300LFM 400LFM 400LFM 500LFM 500LFM 5 5 600LFM 600LFM 0 0 25 30 35 40 45 50 55 60 65 70 75 80 85 Ambient Temperature (℃) Figure 23: Output current vs. ambient temperature and air velocity @Vin=48V(Transverse Orientation, airflow from Vin+ to Vin-,without heat spreader) DS_Q48SC12025_06022015 25 30 35 40 45 50 55 60 65 70 75 80 85 Ambient Temperature (℃) Figure 25: Output current vs. ambient temperature and air velocity @Vin=48V(Transverse Orientation, airflow from Vin+ to Vin-,with heat spreader) E-mail: [email protected] http://www.deltaww.com/dcdc P14 DIGITAL FEATURE DESCRIPTIONS The module has a digital PMBus interface to allow the module to be monitored, controlled and configured by the system. The module supports 4 PMBus signal lines, Data, Clock, SMBALERT (optional), Control (C2 pin, optional), and 2 Address line Addr0 and Addr1. More detail PMBus information can be found in the PMB Power Management Protocol Specification, Part I and part II, revision 1.2; which is shown in http://pmbus.org . Both 100kHz and 400kHz bus speeds are supported by the module. Connection for the PMBus interface should be following the High Power DC specifications given in section 3.1.3 in the SMBus specification V2.0 or the Low Power DC specifications in section 3.1.2. The complete SMBus specification is shown in http://smbus.org. The module contains a data flash used to store configuration settings, which will not be programmed into the device data flash automatically. The STORE_DEFAULT_ALL command must be used to commit the current settings are transfer from RAM to data flash as device defaults. PMBUS Addressing The Module has flexible PMBUS addressing capability. When connect different resistor from Addr0 and Addr1 pin to GND pin, 64 possible addresses can be acquired. The address is in the form of octal digits; Each pin offer one octal digit, and then combine together to form the decimal address as shown in below. Address = 8 * ADDR1 + ADDR0 The module supports the Packet Error Checking (PEC) protocol. It can check the PEC byte provided by the PMBus master, and include a PEC byte in all message responses to the master. And the module also can communicate with the master that does not implement the PEC mechanism. SMBALERT protocol is also supported by the module. SMBALERT line is also a wired-AND signal; by which the module can alert the PMBUS master via pulling the SMBALERT pin to an active low. There are only one way that the master and the module response to the alert of SMBALERT line. This way is for the module used in a system that does not support Alert Response Address (ARA). The module is to retain it’s resistor programmed address, when it is in an ALERT active condition. The master will communicate with the slave module using the programmed address, and using the various READ_STATUS commands to find who cause for the SMBALERT. The CLEAR_FAULTS command will clear the SMBALERT. DS_Q48SC12025_06022015 Corresponded to each octal digit, the requested resistor values are shown in below, and +/-1% resistors accuracy can be accepted. If there is any resistances exceeding the requested range, address 127 will be return. 0-12 and 40, 44, 45, and 55 in decimal address can’t be used, since they are reserved according to the SMBus specifications, and which will also return address 127. E-mail: [email protected] http://www.deltaww.com/dcdc P15 Octal digit Resistor(Kohm) 0 10 1 15.4 2 23.7 3 36.5 4 54.9 5 84.5 6 130 7 200 For commands that set or report all other thresholds, including input voltages, output current, temperature, time and frequency, the supported linear data format is a two byte value with: an 11 bit, two’s complement mantissa , and a 5 bit, two’s complement exponent (scaling factor).The format of the two data bytes is shown as in below. PMBus Data Format The module receives and report date in LINEAR format. The Exponent of the data words is fixed at a reasonable value for the command; altering the exponent is not supported. DIRECT format is not supported by the module. For commands that set or report any voltage thresholds related to the output voltage, the module supports the linear data format consisting of a two byte value with a 16-bit, unsigned mantissa, and a fixed exponent of -12. The format of the two data bytes is shown below: The equation can be written as: (exponent) Value = Mantissa x 2 For example, considering set the turn on threshold of input under voltage lockout to 34V by VIN_ON command; the read/write data can be calculated refer to below process: Get the exponent of Vin, -3; whose binary is 11101 (-3) (-3) Mantissa =Vin/2 =34/2 =272; Converter the calculated Mantissa to hexadecimal 110, then converter to binary 00100010000;Combine the exponent and the mantissa, 11101 and 00100010000; Converter binary 1110100100010000 to hexadecimal E910. The equation can be written as: (-12) Vout = Mantissa x 2 For example, considering set Vout to 12V by VOUT_COMMAND, the read/write data can be calculated refer to below process: (-12) Mantissa =Vout/2 (-12) = 12/2 =49152; Converter the calculated Mantissa to hexadecimal 0xC000. DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P16 SUPPORTED PMBUS COMMANDS The main PMBus commands described in the PMBus 1.2 specification are supported by the module. Partial PMBus commands are fully supported; Partial PMBus commands have difference with the definition in PMBus 1.2 specification. All the supported PMBus commands are detail summarized in below table Transf Compatible with Command Command Command Data -er Code Default Range Data Expon standard description type PMBUS or not? R/W Refer to below byte description; Note Format value limit units -ent Bit field 0x80 / / / Turn the module on or OPERATION 0x01 off by PMBUS / command Configures the combination of ON_OFF_CONFIG 0x1D Read 0x02 (Neg Logic); Yes primary on/off pin and Bit field 0x1D / / / byte 0x1F PMBUS command CLEAR_FAULTS (Pos Logic); Clear any fault bits Send that have been set byte 0x03 Yes / / / / / / This command is Stores operating effective to the Send STORE_DEFAULT_ALL 0x11 parameters from RAM Yes / / / / / parameter of all byte to data flash command in this table. This command can't Restores operating Send RESTORE_DEFAULT_ALL 0x12 parameters from data be issued when the Yes / / / / / byte power unit is flash to RAM running. Read VOUT_MODE 0x20 Read Vo data format Yes mode+exp 0x14 Yes Vout Linear 12 / / / / Volts -12 / byte Set the output voltage VOUT_COMMAND VOUT_MARGIN_HIGH VOUT_MARGIN_LOW FREQUENCY_SWITCH normal value word Set the output voltage R/W margin high value word Set the output voltage R/W margin low value word Set the switching R/W 0x25 0x26 0x33 8 ~13.2 Yes Vout Linear 12.6 <13.0 Volts -12 / Yes Vout Linear 11.4 >10.2 Volts -12 / KHz -2 / Frequency Yes frequency DS_Q48SC12025_06022015 R/W 0x21 word 120 ~ 130 linear 180 E-mail: [email protected] http://www.deltaww.com/dcdc P17 Compatible Transf with -er standard Command Command Data Command description Code Note Format type Default Range Data Expon value limit units -ent 35 33~36 V -3 PMBUS or not? Set the turn on voltage R/W VIN_ON 0x35 threshold of Vin under Vin Yes word VIN_ON should be higher than Linear VIN_OFF voltage lockout Set the turn off voltage R/W VIN_OFF 0x36 threshold of Vin under Vin Yes VIN_ON should be higher than 33 word Linear R/W Vout 31~34 V -3 VIN_OFF voltage lockout Set the output VOUT_OV_FAULT_L 0x40 Must be higher than the value overvoltage fault IMIT Yes word 15 11~16 V -12 of VOUT_COMMAND and Linear threshold. VOUT_OV_WARN_LIMIT; Instructs what action to VOUT_OV_FAULT_ Read Refer to below 0x41 take in response to an RESPONSE Bit field byte 0xB8 / N/A / / description; output overvoltage fault. Set a threshold causing VOUT_OV_WARN_L Must be the same or less than R/W 0x42 an output voltage high IMIT Vout Yes word 15 11~16 V -12 VOUT_OV_FAULT_LIMIT Linear warning. value Must be greater than IOUT_OC_FAULT_LI Set the output overcurrent R/W fault threshold. word 0x46 MIT Iout Yes 33 25~55 A -4 IOUT_OC_WARN_LIMIT Linear value Instructs what action to IOUT_OC_FAULT_R Read Refer to below 0x47 take in response to an ESPONSE Bit field byte 0xF8 / N/A / / description; output overcurrent fault. Set a threshold causing IOUT_OC_WARN_LI Must be less than R/W 0x4A an output current high MIT Iout Yes word 30 25~55 A -4 warning. Set the over temperature OT_FAULT_LIMIT value R/W 0x4F TEMP Yes fault threshold. IOUT_OC_FAULT_LIMIT Linear word 25~14 Deg. 125 Linear Must be greater than -2 0 C / N/A OT_WARN_LIMIT value Instructs what action to OT_FAULT_RESPO Read Refer to below 0x50 take in response to an NSE Bit field byte 0x80 / / description; over temperature fault. DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P18 Compatible with Comman Command Transf Command description d Code Data Default Range Data Expon Format value limit units -ent standard -er type Note PMBUS or not? Must be less OT_WARN_ Set a threshold causing a 0x51 LIMIT TEMP R/W word Yes temperature high warning. than 100 25~140 Deg.C -2 Linear OT_FAULT_LI MIT value VIN_OV_FA Set the input overvoltage fault 0x55 Vin R/W word ULT_LIMIT threshold. VIN_OV_FA Instructs what action to take in Yes 110 48~110 V -3 / 0XF8 / N/A / / Linear Refer to below ULT_RESPO 0x56 response to an input Read byte Bit field description; NSE overvoltage fault. Must be greater Sets the output voltage at which POWER_GO Vout 0x5E the bit 3 of STATUS_WORD R/W word Yes OD_ON 8 11 Linear than V -12 ~13.2 POWER_GOO high byte should be asserted. D_OFF value Must be less Sets the output voltage at which POWER_GO Vout 0x5F the bit 3 of STATUS_WORD R/W word Yes OD_OFF 8 9 Linear than V -12 ~13.2 POWER_GOO high byte should be negated. D_ON value Sets the time from a start Time TON_DELAY 0x60 condition is received until the R/W word Yes 20 5~500 ms -1 / 30 15~500 ms -1 / Bit field / / / / / Bit field / / / / / Bit field / / / / / Linear output voltage starts to rise Sets the time from the output Time TON_RISE 0x61 starts to rise until the voltage R/W word Yes Linear has entered the regulation band. Returns the information with a STATUS_W 0x79 Read Refer to below word description; summary of the module's ORD fault/warning Returns the information of the STATUS_VO Refer to below 0x7A module's output voltage related Read byte UT description; fault/warning Returns the information of the STATUS_IO Refer to below 0x7B module's output current related UT Read byte description; fault/warning DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P19 Compatible with Comman Command Transf Command description d Code Data Default Range Data Expon Format value limit units -ent Bit field / / / / / Bit field / / / / / Bit field / / / / / / / V -3 / / / V -12 / / / A -4 / / / Deg.C -2 / Bit field 0x42 / / / / Bit field 0x00 / / / / Bit field 0x00 / / / / Bit field 0x01 / / / / standard -er type Note PMBUS or not? Returns the information of the STATUS_IN Refer to below 0x7C module's input over voltage and Read byte PUT description; under voltage fault STATUS_TE Returns the information of the Refer to below MPERATUR 0x7D module's temperature related Read byte description; E fault/warning Returns the information of the STATUS_CM Refer to below 0x7E module's communication related Read byte L description; faults. Returns the input voltage of the READ_VIN Read 0x88 READ_VOU module word Returns the output voltage of Read 0x8B T READ_IOUT Vin Yes Linear Vout Yes the module word Returns the output current of the Read 0x8C Linear Iout Yes module word Returns the module's hot spot Read Linear READ_TEM PERATURE_ 0x8D TEMP Yes temperature of the module word Linear 1 PMBUS_RE Reads the revision of the 0x98 VISION Read byte Yes PMBus MFR_C1_C2 Refer to below _ARA_CONF 0xE0 Config C2 pin function R/W byte description; IG MFR_ C2_ Refer to below 0xE1 Config C2 pin logic R/W byte Configure description; MFR_PGOO 0xE2 D Refer to below Config Power Good logic R/W byte description; _POLARITY Total 11 MFR_SERIA Read 0x9E Reads the SN of module L ASCII ‘xxxxxxxxx / block of module use / charact ers DS_Q48SC12025_06022015 The SN number xx’ / / 11 ASCII characters E-mail: [email protected] http://www.deltaww.com/dcdc P20 OPERATION [0x01] Bit number 7: Purpose Enable/Disable the module 6: Reserved 5:4 Margins 3:0 Bit Value Meaning 1 Output is enabled 0 Output is disabled Default Settings， 0x80 1 0 00 No margin 00 01 Margin low(Act on Fault) 10 Margin high(Act on Fault) Reserved 0000 VOUT_OV_FAULT_RESPONSE [0x41] Bit number 7:6 Purpose Response settings Bit Value Meaning Default Settings， 0xB8 10 Unit shuts down and responds according to the 10 retry settings 5:3 Retry setting 111 Unit continuously restarts while fault is present 111 until commanded off 2:0 Delay time setting 000 Unit does not attempt to restart on fault 000 No delay supported 000 IOUT_OC_FAULT_RESPONSE [0x47] Bit number 7:6 Purpose Response settings Bit Value 11 Default Settings， 0xF8 Meaning Unit shuts down and responds according to the 11, retry settings 5:3 Retry settings 111 Unit continuously restarts while fault is present 111 until commanded off 2:0 Delay time setting 000 Unit does not attempt to restart on fault 000 No delay supported 000 OT_FAULT_RESPONSE [0x50] Bit number Purpose Bit Value 7:6 Response settings 10 5:3 Retry settings 111 Default Meaning Settings， 0x80 Unit shuts down and responds according to the 10, retry settings Unit continuously restarts while fault is present 000 until commanded off 2:0 Delay time setting DS_Q48SC12025_06022015 000 Unit does not attempt to restart on fault 000 No delay supported 000 E-mail: [email protected] http://www.deltaww.com/dcdc P21 VIN_OV_FAULT_RESPONSE [0x56] Bit number 7:6 Purpose Response settings Bit Value Meaning Default Settings，0xC0 11 Unit shuts down and responds according to the 11 retry settings 5:3 Retry setting 111 Unit continuously restarts while fault is present 000 until commanded off 2:0 Delay time setting 000 Unit does not attempt to restart on fault 000 No delay supported 000 STATUS_WORD [0x79] High byte Bit number 7 6 5 Purpose An output over voltage fault or warning Meaning 1 Occurred 0 No Occurred 1 Occurred 0 No Occurred An input voltage fault, including over voltage and 1 Occurred undervoltage 0 No Occurred 1 is negated 0 ok An output over current fault or warning 4 Reserved 3 Power_Good 2:0 Bit Value Reserved Low byte Bit number Purpose 7 Reserved 6 OFF (The unit is not providing power to the output, regardless of the reason) 5 4 An output over voltage fault An output over current fault 3 An input under voltage fault 2 A temperature fault or warning 1 0 CML (A communications, memory or logic fault） Bit Value Meaning 1 Occurred 0 No Occurred 1 Occurred 0 No Occurred 1 Occurred 0 No Occurred 1 Occurred 0 No Occurred 1 Occurred 0 No Occurred 1 Occurred； 0 No Occurred Reserved DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P22 STATUS_VOUT [0x7A] Bit number 7 6 5:0 Purpose Output over voltage fault Output over voltage warning Bit Value Meaning 1 Occurred； 0 No Occurred 1 Occurred； 0 No Occurred Reserved STATUS_IOUT [0x7B] Bit number Purpose 7 Output over current fault 6 Reserved 5 Output over current warning 4:0 Bit Value Meaning 1 Occurred； 0 No Occurred 1 Occurred； 0 No Occurred Reserved STATUS_INPUT [0x7C] Bit number 7 6: 5 4 3:0 Purpose Input over voltage fault Bit Value Meaning 1 Occurred； 0 No Occurred 1 Occurred； 0 No Occurred Reserved Input under voltage fault Reserved STATUS_TEMPERATURE [0x7D] Bit number 7 6 5:0 Purpose Over temperature fault Over temperature warning Bit Value Meaning 1 Occurred； 0 No Occurred 1 Occurred； 0 No Occurred Reserved STATUS_CML [0x7E] Bit number 7 6 5 4:0 Purpose Invalid/Unsupported Command Received Invalid/Unsupported Data Received Packet Error Check Failed Bit Value Meaning 1 Occurred； 0 No Occurred 1 Occurred； 0 No Occurred 1 Occurred； 0 No Occurred Reserved DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P23 MFR_C1_C2_ARA_CONFIG [0xE0] Bit number 7:5 4 Purpose Reserved Bit Value 000 ARA 0 Meaning Reserved ARA not functional, module remains at resistor programmed address when SMBLAERT is asserted 3:0 PIN Configuration 0000 C2 pin: POWER_GOOD 0010 C2 pin: ON/OFF (Secondary) MFR_ C2_Configure [0xE1] Bit number 7:2 1 Purpose Reserved Bit Value 000000 ON/OFF Configuration 0 Meaning Reserved Secondary side on/off pin state when mapped to C2 is ignored 1 AND – Primary and Secondary side on/off 0 Secondary Side ON/OFF Logic 0 Negative Logic (Low Enable: Input < 0.8V wrt Vout(-) 1 Positive Logic (High Enable: Input > 2.0V wrt Vout(-) MFR_PGOOD_POLARITY [0xE2] Bit number 7:1 0 Purpose Reserved Power Good Logic DS_Q48SC12025_06022015 Bit Value 0000000 Meaning Reserved 0 Negative PGOOD logic 1 Positive PGOOD logic E-mail: [email protected] http://www.deltaww.com/dcdc P24 MECHANICAL DRAWING( WITH HEAT-SPREADER) *For modules with through-hole pins and the optional heat spreader, they are intended for wave soldering assembly onto system boards, please do not subject such modules through reflow temperature profile. DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P25 MECHANICAL DRAWING( WITHOUT HEAT-SPREADER) Pin Specification: Pins 1-4, 6-8 Pins 5,9 Pins 10-16 1.00mm (0.040”) diameter (All pins are copper with matte Tin plating over Nickel under plating) 2. 1.50mm (0.059”) diameter (All pins are copper with matte Tin plating over Nickel under plating) 1. SQ 0.50mm(0.020’’) ( All pins are copper with gold flash plating) DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P26 RECOMMENDED LAYOUT PART NUMBERING SYSTEM Q 48 S C 120 25 N R Type of Input Number of Product Output Output ON/OFF Pin Length Product Voltage Outputs Series Voltage Current Logic /Type QQuarter Brick 48 - S- C- 36~75V Single Series number 120 12V R - 0.170” D- N - 0.145” Digital pins N- K - 0.110” AAnalog pins Negative Option Code Pin assigment Positive 25 - 25A P - H D Trim Pin Current sharing Heat spreader Case pin C Yes No No No D No Droop No No E No No No No H Yes No Yes No Trim pins I No Droop Yes No S- J No No Yes No Special pins R Yes No Yes Yes S No Droop Yes Yes T No No Yes Yes IIBC pins T- Note for mechaninal pins option: 1. D - Digital pins*: with digital pins & sense pins & trim pin 2. A - Analog pins*: with sense pins & trim pin, without digital pins 3. I - IBC pins*: without digital pins & sense pins & trim pin 4. T - Trim pins: with trim and digital pins, without sense pins 5. S - Special pins: with trim pin, without digital & sense pins DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P27 MODEL LIST MODEL NAME INPUT EFF @ 100%LOAD OUTPUT Q48SC12025NRDH 36V~75V 11A 12V 25A 95.1% Q48SC12025NRAH 36V~75V 11A 12V 25A 95.1% Q48SC12025NRDR 36V~75V 11A 12V 25A 95.1% Q48SC12025NNDH 36V~75V 11A 12V 25A 95.1% * For modules with through-hole pins and the optional heatsink, they are intended for wave soldering assembly onto system boards; please do not subject such modules through reflow temperature profile. Note3: If use VOUT_COMMAND of PMBUS to trim Vout set point, then the function of trim pin(6 pin) will be disabled immediately. And if need enable the function of trim pin(6pin) to trim Vout set point again, should turn off and turn on the input voltage of module to restart module. CONTACT: www.deltaww.com/dcdc Email: [email protected] USA: Telephone: East Coast: 978-656-3993 West Coast: 510-668-5100 Fax: (978) 656 3964 Europe: Phone: +31 (0)20 655 09 67 Fax: +31 (0)20 655 09 99 Asia & the rest of world: Telephone: +886 3 4526107 ext 6220~6224 Fax: +886 3 4513485 WARRANTY Delta offers a two (2) year limited warranty. Complete warranty information is listed on our web site or is available upon request from Delta. Information furnished by Delta is believed to be accurate and reliable. However, no responsibility is assumed by Delta for its use, nor for any infringements of patents or other rights of third parties, which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Delta. Delta reserves the right to revise these specifications at any time, without notice. DS_Q48SC12025_06022015 E-mail: [email protected] http://www.deltaww.com/dcdc P28