Technical Specification Quarter Brick 48Vin 2.5Vout 40A 40 Amp, No Heatsink, Isolated DC/DC Converter The PQ60025QTA40 PowerQor™ Tera quarter-brick converter is a next-generation, board-mountable, isolated, fixed switching frequency DC/DC converter that uses synchronous rectification to achieve extremely high conversion efficiency. The power dissipated by the converter is so low that a heatsink is not required, which saves cost, weight, height, and application effort. All of the power and control components are mounted to the multi-layer PCB substrate with high-yield surface mount technology. Since the PowerQor converter has no explicit thermal connections, it is extremely reliable. The Tera series offers the maximum useable output current for any standard “quarter-brick” module. Operational Features • Ultra-high efficiency, 91% at 20 amp load, 88% at 40 amp load current • Delivers up to 40 amps of output current with minimal derating - no heatsink required • Wide input voltage range: 35V – 75V, with 100V 100ms input voltage transient withstand • Fixed frequency switching provides predictable EMI performance • No minimum load requirement means no preload resistors required Mechanical Features • Industry standard quarter-brick pin-out configuration • Industry standard size: 1.45” x 2.3” • Total height less than 0.43”, permits better airflow and smaller card pitch • Total weight: 42 grams (1.5 oz.), lower mass greatly reduces vibration and shock problems Control Features • On/Off control referenced to input side (positive and negative logic options are available) • Remote sense for the output voltage compensates for output distribution drops • Output voltage trim permits custom voltages and voltage margining Product # PQ60025QTA40 Phone 1-888-567-9596 PQ60025QTA40 Module Protection Features • Input under-voltage lockout disables converter at low input voltage conditions • Output current limit and short circuit protection protects converter from excessive load current or short circuits • Output over-voltage protection protects load from damaging voltages • Thermal shutdown protects converter from abnormal environmental conditions Safety Features • 2000V, 10 MΩ input-to-output isolation provides input/output ground separation • UL/cUL 60950 recognized (US & Canada), basic insulation rating • TUV certified to EN60950 • Meets 72/23/EEC and 93/68/EEC directives which facilitates CE Marking in user’s end product • Board and plastic components meet UL94V-0 flammability requirements Doc.# 005-2QT625C Rev. B 3/6/03 Page 1 Technical Specification Quarter Brick MECHANICAL DIAGRAM 48Vin 2.5Vout 40A 2.30 (58.4) 0.14 (3.6) 2.00 0.300 (50.8) (7.62) 0.150 (3.81) 0.43 (10.9) 1.45 (36.8) 0.300 0.600 0.450 (7.62) (11.43) Top View (15.24) 0.43 Bottom side Clearance (10.9) See Note 9 Side View 0.060+.022/-.032 (1.52+.55/-.81) 0.600 (15.24) Lowest Component Load Board 0.145 (3.68) See Note 3 NOTES PIN CONNECTIONS 1) Pins 1-3, 5-7 are 0.040” (1.02mm) diameter with 0.080” (2.03 mm) diameter standoff shoulders. 2) Pins 4 and 8 are 0.062” (1.57 mm) diameter with 0.100” (2.54 mm) diameter standoff shoulders. 3) Other pin extension lengths available. Recommended pin length is 0.03” (0.76mm) greater than the PCB thickness. 4) All Pins: Material - Copper Alloy Finish - Tin/Lead over Nickel plate 5) Undimensioned components are shown for visual reference only. 6) All dimensions in inches (mm) Tolerances: x.xx +/-0.02 in. (x.x +/-0.5mm) x.xxx +/-0.010 in. (x.xx +/-0.25mm) 7) Weight: 1.5 oz. (42 g) typical 8) Workmanship: Meets or exceeds IPC-A-610C Class II 9) UL/TUV standards require a clearance greater than 0.04” (1.02mm) between input and output for Basic insulation. This issue should be considered if any copper traces are on the top side of the user’s board. Note that the ferrite cores are considered part of the input/primary circuit. Product # PQ60025QTA40 Phone 1-888-567-9596 Pin No. Name Function 1 Vin(+) Positive input voltage 2 ON/OFF TTL input to turn converter on and off, referenced to Vin(-), with internal pull up. 3 Vin(-) Negative input voltage 4 Vout(-) Negative output voltage 5 SENSE(-) Negative remote sense1 6 TRIM Output voltage trim2 7 SENSE(+) Positive remote sense3 8 Vout(+) Positive output voltage Notes: 1. Pin 5 must be connected to Vout(-). 2. Leave Pin 6 open for nominal output voltage. 3. Pin 7 must be connected to Vout(+). Doc.# 005-2QT625C Rev. B 3/6/03 Page 2 Technical Specification Quarter 48Vin 2.5Vout 40A Brick PQ60025QTA40 ELECTRICAL CHARACTERISTICS TA=25°C, airflow rate=300 LFM, Vin=48Vdc unless otherwise noted; full operating temperature range is -40°C to +100°C ambient temperature with appropriate power derating. Specifications subject to change without notice. Parameter Min. Typ. Max. Units 100 80 100 2000 100 125 18 V V V V °C °C V Notes & Conditions ABSOLUTE MAXIMUM RATINGS Input Voltage Non-Operating Operating Operating Transient Protection Isolation Voltage (input to output) Operating Temperature Storage Temperature Voltage at ON/OFF input pin -40 -55 -2 INPUT CHARACTERISTICS Operating Input Voltage Range Input Under-Voltage Lockout Turn-On Voltage Threshold Turn-Off Voltage Threshold Lockout Hysteresis Voltage Maximum Input Current No-Load Input Current Disabled Input Current Inrush Current Transient Rating Response to Input Transient Input Reflected-Ripple Current Recommended Input Fuse Input Filter Component Values (C1\L\C2) Recommended External Input Capacitance OUTPUT CHARACTERISTICS Output Voltage Set Point Output Voltage Regulation Over Line Over Load Over Temperature Total Output Voltage Range Output Voltage Ripple and Noise Peak-to-Peak RMS Operating Output Current Range Output DC Current-Limit Inception Output DC Current-Limit Shutdown Voltage Back-Drive Current Limit while Enabled Back-Drive Current Limit while Disabled Maximum Output Capacitance 35 48 75 V 32 28.5 2.5 33 29.5 3.5 34 30.5 4.5 4.5 75 3 V V V A mA mA A 2s mV mA A µF\µH\µF µF 55 1.6 0.01 150 10 33 2.475 2.427 0 44 0.5 0 DYNAMIC CHARACTERISTICS Input Voltage Ripple Rejection Output Voltage during Load Current Transient Step Change in Output Current (0.1A/µs) Step Change in Output Current (1A/µs) Settling Time Turn-On Transient Turn-On Time Start-Up Inhibit Time Output Voltage Overshoot EFFICIENCY 100% Load 50% Load 1\5\3 47 2.500 2.525 V +0.1 \ 2 +0.1 \ 2 +13 +0.2 \ 5 +0.2 \ 5 +38 2.573 %\mV %\mV mV V 50 10 100 20 40 51 mV mV A A V A mA µF 47.5 1.36 1.8 10 over sample, line, load, temperature & life 500MHz bandwidth; Fig. 13 & 16 Full Load, see Figures 13 & 16 Full Load, see Figures 13 & 16 Output Voltage 10% Low Max negative current drawn from output Max negative current drawn from output 2.5Vout at 40A Resistive Load 80 190 400 mV mV µs 50% to 75% to 50% Iout max; Figure 11 50% to 75% to 50% Iout max; Figure 12 to within 1% Vout nom ms ms % Full load, Vout=90% nom.; Figs. 9 & 10 -40°C to +125°C; Figure F 10,000 µF load capacitance, Iout = 0A % % Figures 1 - 4 Figures 1 - 4 125 125 125 °C °C °C Package rated to 150°C UL rated max operating temp 130°C See Figures 5 - 8 for derating curves 470 V MΩ pF 86 89 88 91 Semiconductor Junction Temperature Board Temperature Transformer Temperature 2000 10 Phone 1-888-567-9596 see Figure 13 120 Hz; Fig. 20 TEMPERATURE LIMITS FOR POWER DERATING CURVES Product # PQ60025QTA40 1000V/ms input transient; Figure 17 P-P thru 10µH inductor; Figs. 13 & 15 fast blow external fuse recommended internal values, see Figure E dB 4 200 0 Isolation Voltage Isolation Resistance Isolation Capacitance 2.5 50 25,000 100% Load, 35 Vin 71 180 ISOLATION CHARACTERISTICS 7 continuous continuous 100ms transient; Figure 17 Basic level, Pollution Degree 2 8 215 Doc.# 005-2QT625C Rev. B 3/6/03 Page 3 Technical Specification Quarter 48Vin 2.5Vout 40A Brick ELECTRICAL CHARACTERISTICS (Continued) Parameter P FEATURE CHARACTERISTICS Switching Frequency ON/OFF Control (Option P) Off-State Voltage On-State Voltage ON/OFF Control (Option N) Off-State Voltage On-State Voltage ON/OFF Control (Either Option) Pull-Up Voltage Pull-Up Resistance Output Voltage Trim Range Output Voltage Remote Sense Range Output Over-Voltage Protection Over-Temperature Shutdown Over-Temperature Shutdown Restart Hysteresis Min. Typ. Max. Units 180 210 240 kHz -2 2.4 0.8 18 V V 2.4 -2 18 0.8 V V 9.2 V kΩ % % % °C °C -20 Vin/6.5 40 117 RELIABILITY CHARACTERISTICS Calculated MTBF Calculated MTBF Demonstrated MTBF +10 +10 127 122 125 10 Notes & Conditions Figures A, B Measured across Pins 8 & 4; Figure C Measured across Pins 8 & 4 Over full temp range; % of nominal Vout Average PCB Temperature 106 Hrs. Telcordia TR-NWT-000332; 80% load,300LFM, 40oC Ta 106 Hrs. MIL-HDBK-217F; 80% load, 300LFM, 40oC Ta 106 Hrs. Field demonstrated MTBF 2.1 1.75 TBD STANDARDS COMPLIANCE Parameter P Notes STANDARDS COMPLIANCE UL/cUL 60950 EN60950 72/23/EEC 93/68/EEC Needle Flame Test (IEC 695-2-2) IEC 61000-4-2 GR-1089-CORE Telcordia (Bellcore) GR-513 File # E194341, Basic insulation & pollution degree 2 Certified by TUV test on entire assembly; board & plastic components UL94V-0 compliant ESD test, 8kV - NP, 15kV air - NP Section 7 - electrical safety, Section 9 - bonding/grounding • An external input fuse must always be used to meet these safety requirements QUALIFICATION TESTING Parameter P QUALIFICATION TESTING Life Test Vibration Mechanical Shock Temperature Cycling Power/Thermal Cycling Design Marginality Humidity Solderability # Units 32 5 5 10 5 5 5 15 pins Test Conditions 95% rated Vin and load, units at derating point, 1000 hours 10-55Hz sweep, 0.060” total excursion,1 min./sweep, 120 sweeps for 3 axis 100g minimum, 2 drops in x and y axis, 1 drop in z axis -40°C to 100°C, unit temp. ramp 15°C/min., 500 cycles Toperating = min to max, Vin = min to max, full load, 100 cycles Tmin-10°C to Tmax+10°C, 5°C steps, Vin = min to max, 0-105% load 85°C, 85% RH, 1000 hours, 2 minutes on and 6 hours off MIL-STD-883, method 2003 • Extensive characterization testing of all SynQor products and manufacturing processes is performed to ensure that we supply robust, reliable product. Contact factory for more information about Proof of Design and Proof of Manufacturing processes. OPTIONS PATENTS SynQor provides various options for Logic Sense, Pin Length and Feature Set for this family of DC/DC converters. Please consult the last page of this specification sheet for information on available options. SynQor is protected under various patents, including but not limited to U.S. Patent # 5,999,417. Product # PQ60025QTA40 Phone 1-888-567-9596 Doc.# 005-2QT625C Rev. B 3/6/03 Page 4 Performance Curves Quarter 48Vin 2.5Vout 40A Brick 100 95 95 94 93 92 Efficiency (%) Efficiency (%) 90 85 80 75 70 60 0 4 8 12 16 20 24 28 32 36 90 89 88 25 C 40 C 87 36 Vin 48 Vin 75 Vin 65 91 86 55 C 85 0 40 100 Figure 1: Efficiency at nominal output voltage vs. load current for minimum, nominal, and maximum input voltage at 25°C. 300 400 500 Figure 2: Efficiency at nominal output voltage and 60% rated power vs. airflow rate for ambient air temperatures of 25°C, 40°C, and 55°C (nominal input voltage). 14 8.0 12 7.0 Power Dissipation (W) Power Dissipation (W) 200 Air Flow (LFM) Load Current (A) 10 8 6 4 36 Vin 48 Vin 75 Vin 2 4 8 12 16 20 24 28 32 36 5.0 4.0 25 C 40 C 55 C 3.0 2.0 0 0 6.0 40 0 100 200 300 400 500 Air Flow (LFM) Load Current (A) Figure 3: Power dissipation at nominal output voltage vs. load current for minimum, nominal, and maximum input voltage at 25°C. Figure 4: Power dissipation at nominal output voltage and 60% rated power vs. airflow rate for ambient air temperatures of 25°C, 40°C, and 55°C (nominal input voltage). 40 35 30 Iout (A) 25 20 15 400 LFM (2.0 m/s) 10 300 LFM (1.5 m/s) 5 100 LFM (0.5 m/s) 200 LFM (1.0 m/s) 0 LFM (0 m/s) 0 0 25 40 55 70 85 Ambient Air Temperature (oC) Figure 5: Maximum output power derating curves vs. ambient air temperature for airflow rates of 0 LFM through 400 LFM with air flowing across the converter from pin 3 to pin 1 (nominal input voltage). Product # PQ60025QTA40 Phone 1-888-567-9596 Semiconductor junction temperature is within 1°C of surface temperature Figure 6: Thermal plot of converter at 36 amp load current with 55°C air flowing at the rate of 200 LFM. Air is flowing across the converter from pin 3 to pin 1 (nominal input voltage). Doc.# 005-2QT625C Rev. B 3/6/03 Page 5 Performance Curves Quarter Brick 48Vin 2.5Vout 40A 40 35 30 Iout (A) 25 20 15 400 LFM (2.0 m/s) 10 300 LFM (1.5 m/s) 5 100 LFM (0.5 m/s) 200 LFM (1.0 m/s) 0 LFM (0 m/s) 0 0 25 40 55 70 85 Ambient Air Temperature (oC) Semiconductor junction temperature is within 1°C of surface temperature Figure 7: Maximum output power derating curves vs. ambient air temperature for airflow rates of 0 LFM through 400 LFM with air flowing lengthwise from output to input (nominal input voltage). Figure 8: Thermal plot of converter at 35 amp load current with 55°C air flowing at the rate of 200 LFM. Air is flowing lengthwise from output to input (nominal input voltage). Figure 9: Turn-on transient at full rated load (resistive load) (2 ms/div) Ch 1: Vout (1V/div) Ch 2: ON/OFF input (5V/div) Figure 10: Turn-on transient at zero load current (2 ms/div). Ch 1: Vout (1V/div) Ch 2: ON/OFF input (5V/div) Figure 11: Output voltage response to step-change in load current (50%-75%50% of Iout(max); dI/dt = 0.1A/µs). Load cap: 10µF, 100 mΩ ESR tantalum capac- Figure 12: Output voltage response to step-change in load current (50%-75%50% of Iout(max): dI/dt = 1A/µs). Load cap: 470µF, 30 mΩ ESR tantalum capacitor and 1µF ceramic cap. Ch 1: Vout (100mV/div), Ch 2: Iout (10A/div). itor and 1µF ceramic capacitor. Ch 1: Vout (100mV/div), Ch 2: Iout (10A/div). Product # PQ60025QTA40 Phone 1-888-567-9596 Doc.# 005-2QT625C Rev. B 3/6/03 Page 6 Performance Curves Quarter Brick Figure 15 10 µH source impedance Figure 14 Figure 16 iS VSOURCE 48Vin 2.5Vout 40A iC 47 µF, ≅1Ω ESR electrolytic capacitor DC/DC Converter VOUT 1 µF 10 µF, ceramic 100mΩ ESR capacitor tantalum capacitor Figure 13: Test set-up diagram showing measurement points for Input Terminal Ripple Current (Figure 14), Input Reflected Ripple Current (Figure 15) and Output Voltage Ripple (Figure 16). Figure 14: Input Terminal Ripple Current, ic, at full rated output current and nominal input voltage with 10µH source impedance and 47µF electrolytic capacitor (100 mA/div). See Figure 13. Figure 15: Input reflected ripple current, is, through a 10 µH source inductor at nominal input voltage and rated load current (10 mA/div). See Figure 13. Figure 16: Output voltage ripple at nominal input voltage and rated load current (20 mV/div). Load capacitance: 1µF ceramic capacitor and 10µF tantalum capacitor. Bandwidth: 500 MHz. See Figure 13. Figure 17: Output voltage response to step-change in input voltage (50V to 100V in 40µs). Load cap: 10µF, 100 mΩ ESR tantalum capacitor and 1µF ceramic cap. Ch 1: Vout (100mV/div), Ch 2: Vin (20V/div). Figure 18: Load current (20A/div) as a function of time when the converter attempts to turn on into a 1 mΩ short circuit. Bottom trace (2ms/div) is an expansion of the on-time portion of the top trace. Product # PQ60025QTA40 Phone 1-888-567-9596 Doc.# 005-2QT625C Rev. B 3/6/03 Page 7 Performance Curves Quarter 48Vin 2.5Vout 40A Brick 0.1 0 0.01 36 Vin 48 Vin 75 Vin 0.001 Forward Transmission (dB) Output Impedance ( Ω ) -10 -20 -30 -40 36 Vin 48 Vin 75 Vin -50 -60 -70 -80 -90 -100 -110 0.0001 10 100 1,000 10,000 10 100,000 100 1,000 10,000 100,000 Hz Hz Figure 19: Magntiude of incremental output impedance (Zout = vout/iout) for minimum, nominal, and maximum input voltage at full rated power. Figure 20: Magnitude of incremental forward transmission (FT = vout/vin) for minimum, nominal, and maximum input voltage at full rated power. 0 100 -20 36 Vin 48 Vin 75 Vin -30 -40 Input Impedance (Ω ) Reverse Transmission (dB) -10 10 36 Vin 48 Vin 75 Vin 1 -50 -60 0.1 10 100 1,000 10,000 100,000 Hz 100 1,000 10,000 100,000 Hz Figure 21: Magnitude of incremental reverse transmission (RT = iin/iout) for minimum, nominal, and maximum input voltage at full rated power. Product # PQ60025QTA40 10 Phone 1-888-567-9596 Figure 22: Magnitude of incremental input impedance (Zin = vin/iin) for minimum, nominal, and maximum input voltage at full rated power. Doc.# 005-2QT625C Rev. B 3/6/03 Page 8 Technical Specification Quarter Brick 48Vin 2.5Vout 40A BASIC OPERATION AND FEATURES CONTROL FEATURES The PowerQor series converter uses a two-stage power circuit topology. The first stage is a buck-converter that keeps the output voltage constant over variations in line, load, and temperature. The second stage uses a transformer to provide the functions of input/output isolation and voltage step-down to achieve the low output voltage required. REMOTE ON/OFF (Pin 2): The ON/OFF input, Pin 2, permits the user to control when the converter is on or off. This input is referenced to the return terminal of the input bus, Vin(-). There are two versions of the converter that differ by the sense of the logic used for the ON/OFF input. Both the first stage and the second stage switch at a fixed frequency for predictable EMI performance. Rectification of the transformer’s output is accomplished with synchronous rectifiers. These devices, which are MOSFETs with a very low onstate resistance, dissipate far less energy than Schottky diodes. This is the primary reason that the PowerQor converter has such high efficiency, even at very low output voltages and very high output currents. Dissipation throughout the converter is so low that it does not require a heatsink for operation. Since a heatsink is not required, the PowerQor converter does not need a metal baseplate or potting material to help conduct the dissipated energy to the heatsink. The PowerQor converter can thus be built more simply and reliably using high yield surface mount techniques on a PCB substrate. The PowerQor series of half-brick and quarter-brick converters uses the industry standard footprint and pin-out configuration. In the positive logic version, the ON/OFF input is active high (meaning that a high turns the converter on). In the negative logic version, the ON/OFF signal is active low (meaning that a low turns the converter on). Figure A details five possible circuits for driving the ON/OFF pin. Figure B is a detailed look of the internal ON/OFF circuitry. REMOTE SENSE(+) (Pins 7 and 5): The SENSE(+) inputs correct for voltage drops along the conductors that connect the converter’s output pins to the load. Pin 7 should be connected to Vout(+) and Pin 5 should be connected to Vout(-) at the point on the board where regulation is desired. A remote connection at the load can adjust for a voltage drop only as large as that specified in this datasheet, that is [Vout(+) - Vout(-)] – [SENSE(+) - SENSE(-)] < Sense Range % x Vout Pins 7 and 5 must be connected for proper regulation of the output voltage. If these connections are not made, the converter will deliver an output voltage that is slightly lower than its specified value. ON/OFF ON/OFF ON/OFF Vin(_) Vin(_) Vin(_) Remote Enable Circuit Negative Logic (Permanently Enabled) ON/OFF Positive Logic (Permanently Enabled) 5V Vin(+) 5V 274k ON/OFF 50k TTL TTL/ CMOS ON/OFF Vin(_) Vin(_) Open Collector Enable Circuit Vin(_) Direct Logic Drive Figure A: Various circuits for driving the ON/OFF pin. Product # PQ60025QTA40 100pF 50k Phone 1-888-567-9596 Figure B: Internal ON/OFF pin circuitry Doc.# 005-2QT625C Rev. B 3/6/03 Page 9 Technical Specification Quarter Brick Note: the output over-voltage protection circuit senses the voltage across the output (pins 8 and 4) to determine when it should trigger, not the voltage across the converter’s sense leads (pins 7 and 5). Therefore, the resistive drop on the board should be small enough so that output OVP does not trigger, even during load transients. OUTPUT VOLTAGE TRIM (Pin 6): The TRIM input permits the user to adjust the output voltage across the sense leads up or down according to the trim range specifications. To decrease the output voltage, the user should connect a resistor between Pin 6 and Pin 5 (SENSE(-) input). For a desired decrease of the nominal output voltage, the value of the resistor should be Rtrim-down = - 10.22 (511 ∆%) (kΩ) where ∆% = – Vdesired (Vnominal ) x 100% Vnominal To increase the output voltage, the user should connect a resistor between Pin 6 and Pin 7 (SENSE(+) input). For a desired increase of the nominal output voltage, the value of the resistor should be Rtrim-up = ( 5.11VOUT(100+∆%) _ 511 _ 1.225∆% ∆% 10.22 ) Note: the TRIM feature does not affect the voltage at which the output over-voltage protection circuit is triggered. Trimming the output voltage too high may cause the over-voltage protection circuit to engage, particularly during transients. It is not necessary for the user to add capacitance at the Trim pin. The node is internally bypassed to eliminate noise. Total DC Variation of Vout: For the converter to meet its full specifications, the maximum variation of the DC value of Vout, due to both trimming and remote load voltage drops, should not be greater than that specified for the output voltage trim range. PROTECTION FEATURES Input Under-Voltage Lockout: The converter is designed to turn off when the input voltage is too low, helping avoid an input system instability problem, described in more detail in the application note titled “Input System Instability”. The lockout circuitry is a comparator with DC hysteresis. When the input voltage is rising, it must exceed the typical Turn-On Voltage Threshold value (listed on the specification page) before the converter will turn on. Once the converter is on, the input voltage must fall below the typical Turn-Off Voltage Threshold value before the converter will turn off. Output Current Limit: The maximum current limit remains constant as the output voltage drops. However, once the impedance of the short across the output is small enough to make the output voltage drop below the specified Output DC CurrentLimit Shutdown Voltage, the converter turns off. (kΩ) where VOUT = Nominal Output Voltage Figure C graphs the relationship between the trim resistor value and Rtrim-up and Rtrim-down, showing the total range the output voltage can be trimmed up or down. 10,000 Trim Resistance (kOhms) 48Vin 2.5Vout 40A The converter then enters a “hiccup mode” where it repeatedly turns on and off at a 5 Hz (nominal) frequency with a 5% duty cycle until the short circuit condition is removed. This prevents excessive heating of the converter or the load board. Output Over-Voltage Limit: If the voltage across the output pins exceeds the Output Over-Voltage Protection threshold, the converter will immediately stop switching. This prevents damage to the load circuit due to 1) excessive series resistance in output current path from converter output pins to sense point, 2) a release of a short-circuit condition, or 3) a release of a current limit condition. Load capacitance determines exactly how high the output voltage will rise in response to these conditions. After 200 ms the converter will automatically restart. 1,000 100 10 0 2 4 6 8 10 % increase Vout 12 14 16 18 % decrease Vout Figure C: Trim Graph for 2.5Vout module Product # PQ60025QTA40 Phone 1-888-567-9596 20 Over-Temperature Shutdown: A temperature sensor on the converter senses the average temperature of the module. The thermal shutdown circuit is designed to turn the converter off when the temperature at the sensed location reaches the Doc.# 005-2QT625C Rev. B 3/6/03 Page 10 Technical Specification Quarter 48Vin 2.5Vout 40A Brick More detailed information is available in the application note titled “EMI Characteristics” on the SynQor website. Over-Temperature Shutdown value. It will allow the converter to turn on again when the temperature of the sensed location falls by the amount of the Over-Temperature Shutdown Restart Hysteresis value. APPLICATION CONSIDERATIONS Input System Instability: This condition can occur because any DC/DC converter appears incrementally as a negative resistance load. A detailed application note titled “Input System Instability” is available on the SynQor web site (www.synqor.com) which provides an understanding of why this instability arises, and shows the preferred solution for correcting it. Application Circuits: Figure D below provides a typical circuit diagram which details the input filtering and voltage trimming. Input Filtering and External Capacitance: Figure E below provides a diagram showing the internal input filter components. This filter dramatically reduces input terminal ripple current, which otherwise could exceed the rating of an external electrolytic input capacitor. The recommended external input capacitance is specified in the “Input Characterisitcs” section. Electrolytic Capacitor 33µF ESR ≅1Ω External Input Filter Vin Vin(+) Vout(+) Vsense(+) ON/OFF Trim Vsense(_) Vin(_) Rtrim-up or Cload Rtrim-down Iload Vout(_) Figure D: Typical application circuit (negative logic unit, permanently enabled). L Vin(+) C1 C2 Vin(_) Figure E: Internal Input Filter Diagram (component values listed on page 3). Product # PQ60025QTA40 Phone 1-888-567-9596 Doc.# 005-2QT625C Rev. B 3/6/03 Page 11 Technical Specification Quarter 48Vin 2.5Vout 40A Brick Startup Inhibit Period: The Startup Inhibit Period ensures that the converter will remain off for at least 200ms when it is shut down for any reason. When an output short is present, this generates a 5Hz "hiccup mode," which prevents the converter from overheating. In all, there are seven ways that the converter can be shut down, initiating a Startup Inhibit Period: Before time t0, when the input voltage is below the UVL threshold, the unit is disabled by the Input Under-Voltage Lockout feature. When the input voltage rises above the UVL threshold, the Input Under-Voltage Lockout is released, and a Startup Inhibit Period is initiated. At the end of this delay, the ON/OFF pin is evaluated, and since it is active, the unit turns on. • Input Under-Voltage Lockout At time t1, the unit is disabled by the ON/OFF pin, and it cannot be enabled again until the Startup Inhibit Period has elapsed. • Input Over-Voltage Shutdown (not present in Quarter-brick) • Output Over-Voltage Protection • Over Temperature Shutdown When the ON/OFF pin goes high after t2, the Startup Inhibit Period has elapsed, and the output turns on within the typical Turn-On Time. • Current Limit • Short Circuit Protection • Turned off by the ON/OFF input Figure F shows three turn-on scenarios, where a Startup Inhibit Period is initiated at t0, t1, and t2: Vin Under-Voltage Lockout Turn-On Threshold ON/OFF (pos logic) ON OFF OFF ON ON 4ms (typical Vout turn on time) 200ms (typical start-up inhibit period) t0 200ms 200ms t1 t t2 Figure F: Startup Inhibit Period (turn-on time not to scale) Product # PQ60025QTA40 Phone 1-888-567-9596 Doc.# 005-2QT625C Rev. B 3/6/03 Page 12 Technical Specification Quarter 48Vin 2.5Vout 40A Brick PART NUMBERING SYSTEM ORDERING INFORMATION The part numbering system for SynQor’s PowerQor DC/DC converters follows the format shown in the example below. The tables below show the valid model numbers and ordering options for converters in this product family. When ordering SynQor converters, please ensure that you use the complete 15 character part number consisting of the 12 character base part number and the additional 3 characters for options. PQ 48 033 H T A 50 N K S Options (see Ordering Information) Output Current Thermal Design Performance Level Package Size Output Voltage Input Voltage Product Family The first 12 characters comprise the base part number and the last 3 characters indicate available options. Although there are no default values for enable logic and pin length, the most common options are negative logic and 0.145” pins. These part numbers are more likely to be readily available in stock for evaluation and prototype quantities. Model Number Input Voltage PQ60010QTA40xyz PQ60012QTA40xyz PQ60015QTA40xyz PQ60018QTA40xyz PQ60025QTA40xyz PQ60033QTA35xyz 35 - 75 V 35 - 75 V 35 - 75 V 35 - 75 V 35 - 75 V 35 - 75 V Output Max Output Voltage Current 1.0 V 40 A 1.2 V 40 A 1.5 V 40 A 1.8 V 40 A 2.5 V 40 A 3.3 V 35 A The following option choices must be included in place of the x y z spaces in the model numbers listed above. Options Description: x y z Enable Logic Pin Length Feature Set K - 0.110" P - Positive N - 0.145" S - Standard N - Negative R - 0.180" Y - 0.250" Application Notes A variety of application notes and technical white papers can be downloaded in pdf format at www.synqor.com. Contact SynQor for further information: Phone: Toll Free: Fax: E-mail: Web: Address: Product # PQ60025QTA40 508-485-8434 888-567-9596 508-485-8414 [email protected] www.synqor.com 188 Central Street Hudson, MA 01749 Phone 1-888-567-9596 Warranty SynQor offers a three (3) year limited warranty. Complete warranty information is listed on our web site or is available upon request from SynQor. Information furnished by SynQor is believed to be accurate and reliable. However, no responsibility is assumed by SynQor 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 SynQor. Doc.# 005-2QT625C Rev. B 3/6/03 Page 13