Technical Specification PQ24120QEx25 18-36 V 50V 12V 300W 2250V dc Quarter-brick Input Transient Input Output Max Power Isolation DC-DC Converter The PQ24120QEx25 PowerQor Exa Quarter-brick converter is a next-generation, board-mountable, isolated, fixed switching frequency DC-DC converter. The Exa series offers industry leading power density for standard isolated DC-DC converters with both a wide input range and a tightly regulated output. This module supplies an isolated step down voltage from 18-36 V to 12V and provides more available power and higher efficiency than competitive converters. RoHS Compliant (see last page). Protection Features • • • • • • • • Input under-voltage lockout disables converter at low Vin conditions Output current limit Short circuit protection Protection from permanent damage and hazardous conditions Active back bias limit Smooth startup with external load induced pre-bias Auto-recovery output OVP protects load from damaging voltages Thermal shutdown protects converter from abnormal conditions Mechanical Features • • • • Industry standard quarter-brick pin-out Open frame Size: 1.45" x 2.30" x 0.445" (36.8 x 58.4 x 11.3mm) Open frame weight: 1.5 oz (46 g) Flanged pins designed to permit surface mount soldering, avoid wave solder using FPiP technique on open frame units PQ24120QEx25 Model Operational Features • • • • • • • High efficiency, 96% at half rated load current Delivers 25A full power with minimal derating - no heatsink required Operating input voltage range: 18-36 V Input voltage transient capability: 50V, 1,000ms Fixed frequency switching provides predictable EMI No minimum load requirement Wide output voltage Trim range (-50% to +10%), see trim section Control Features • On/Off control referenced to input side • Positive and negative logic options are available Page No. Safety Features • UL 60950-1/R2011-12 • EN60950-1/A2:2013 • CAN/CSA-C22.2 No. 60950-1/A1:2011 Product # PQ24120QEx25 Contents Phone 1-888-567-9596 Mechanical Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Standards & Qualifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Technical Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Applications Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 www.synqor.com Doc.# 005-0006328 Rev. D 07/16/14 Page 1 Input: 18-36 V Output: 12V Current: 25A Package: Quarter-brick Open Frame Mechanical Diagram .600[15.24] .450[11.43] .300[7.62] .150[3.81] .180 [4.57] 4 5 6 7 8 2.300 [58.42] 1.450 [36.83] .058±.013 [1.47±0.33 ] Bottomside Clearance .445 ±.013 [11.3 ±0.338] Overall Height NOTES 3 2 1 .425 ± .020 [10.8± 0.5] .300[7.62] .600[15.24] PIN DESIGNATIONS 1)PINS 1-3, 5-7 ARE 0.040” (1.02mm) DIA. WITH 0.080” (2.03mm) DIA. STANDOFF SHOULDERS 2)PINS 4 AND 8 ARE 0.062” (1.57mm) DIA. WITH 0.100” (2.54mm) DIA. STANDOFF SHOULDERS Pin Label Function 1 Vin(+) Positive input TTL input to turn converter on and off, 2 ON/OFF referenced to Vin(-), with internal pull up 3 Vin(-) Negative input voltage 4 Vout(-) Negative output voltage SENSE 5 Negative remote sense. See note 1 (-) 6 TRIM Output voltage trim. See note 2 SENSE 7 Positive remote sense. See note 3 (+) 8 Vout(+) Positive output voltage Notes: 1)SENSE(–) should be connected to Vout(–) either remotely or at the converter. 2)Leave TRIM pin open for nominal output voltage. 3)ALL PINS: MATERIAL: COPPER ALLOY FINISH: MATTE TIN OVER NICKEL PLATE 4)UNDIMENSIONED COMPONENTS ARE SHOWN FOR VISUAL REFERENCE ONLY 5)ALL DIMENSIONS IN INCHES(mm) 6)TOLERANCES: X.XXIN +/-0.02 (X.Xmm +/-0.5mm) X.XXXIN +/-0.010 (X.XXmm +/-0.25mm) 7)WEIGHT: 1.5 oz (46 g) TYPICAL 8)WORKMANSHIP: MEETS OR EXCEEDS IPC-A-610 CLASS II 3)SENSE(+) should be connected to Vout(+) either remotely or at the converter. Product # PQ24120QEx25 Phone 1-888-567-9596 www.synqor.com Doc.# 005-0006328 Rev. D 07/16/14 Page 2 Input: 18-36 V Output: 12V Current: 25A Package: Quarter-brick Baseplated Mechanical Diagram SEATING PLANE HEIGHT 0.544 0.025 [ 13.82 0.63 ] 1.510 [38.35] 1.030 [26.16] PIN EXTENSION 0.180 [4.57] 0.450 [11.43] 0.150 [3.81] 4 5 6 7 8 TOP VIEW 1.860 [47.24] 0.004 [0.10] 2.000 [50.80] 2.340 [59.44] 0.08 [2.0] 1 0.215 0.020 [5.46 0.50] BOTTOMSIDE CLEARANCE 0.058 0.013 [ 1.47 0.33 ] THREADED INSERT SEE NOTE 1 (4 PLCS) 1)APPLIED TORQUE PER M3 SCREW 4in-lb RECOMMENDED (5in-lb LIMIT) SCREW SHOULD NOT EXCEED 0.100” (2.54mm) DEPTH BELOW THE SURFACE OF THE BASEPLATE. 2)BASEPLATE FLATNESS TOLERANCE IS 0.004” (.10mm) TIR FOR SURFACE. 3)PINS 1-3, 5-7 ARE 0.040” (1.02mm) DIA. WITH 0.080” (2.03mm) DIA. STANDOFFS. 4)PINS 4 AND 8 ARE 0.080” (2.03mm) DIA. WITH 0.125” (3.18mm) DIA. STANDOFFS. 5)ALL PINS: MATERIAL: COPPER ALLOY FINISH: MATTE TIN OVER NICKEL PLATE 6)WEIGHT: 3.0 oz (85 g) TYPICAL 7)ALL DIMENSIONS IN INCHES(mm) TOLERANCES: X.XXIN +/-0.02 (X.Xmm +/-0.5mm) X.XXXIN +/-0.010 (X.XXmm +/-0.25mm) Phone 1-888-567-9596 2 1 0.300 [7.62] 0.600 [15.24] NOTES Product # PQ24120QEx25 3 www.synqor.com PIN DESIGNATIONS Pin Label Function 1 Vin(+) Positive input TTL input to turn converter on and off, 2 ON/OFF referenced to Vin(-), with internal pull up 3 Vin(-) Negative input voltage 4 Vout(-) Negative output voltage SENSE 5 Negative remote sense. See note 1 (-) 6 TRIM Output voltage trim. See note 2 SENSE 7 Positive remote sense. See note 3 (+) 8 Vout(+) Positive output voltage Notes: 1)SENSE(–) should be connected to Vout(–) either remotely or at the converter. 2)Leave TRIM pin open for nominal output voltage. 3)SENSE(+) should be connected to Vout(+) either remotely or at the converter. Doc.# 005-0006328 Rev. D 07/16/14 Page 3 Input: 18-36 V Output: 12V Current: 25A Package: Quarter-brick Technical Specifications PQ24120QEx25 Electrical Characteristics Ta = 25 °C, airflow rate = 300 LFM, Vin = 24V dc 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. ABSOLUTE MAXIMUM RATINGS Input Voltage Non-Operating Operating Operating Transient Protection Insulation Voltage Input to Output Operating Temperature Storage Temperature Voltage at ON/OFF input pin INPUT CHARACTERISTICS Operating Input Voltage Range Input Under-Voltage Lockout Turn-On Voltage Threshold Turn-Off Voltage Threshold Lockout Voltage Hysteresis Maximum Input Current No-Load Input Current Disabled Input Current Response to Input Transient Input Reflected Ripple Current Input Terminal Ripple Current Recommended Input Fuse Recommended External Input Capacitance Input Filter Component Values (C1\Lin\C2) 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 Electrolytic EFFICIENCY 100% Load 50% Load Product # PQ24120QEx25 Typ. Max. -1 -40 -45 -2 Units Notes & Conditions 50 40 50 V V V 2250 100 125 9 V dc °C °C V 18 24 36 V 16.2 14.7 17.0 15.5 1.5 17.9 16.3 V V V A mA mA V mA mA A µF 360 4 1.9 2 200 22 450 6 30 220 0.1\0.22\28.3 11.80 12.12 V ±0.25 ±0.25 ±0.35 ±0.35 300 12.36 % % mV V 100 24 0 27.5 Phone 1-888-567-9596 30.0 5 5 3 25 32.5 95 96 www.synqor.com 4 12 100% Load, 18V Vin, Trimmed up 10% 0.25V/μs input transient RMS thru 4.7μH inductor RMS Fast acting external fuse recommended Typical ESR 0.1-0.2Ω; Figure 13 µF\µH\µF Internal values; see Figure D 12.00 -300 11.64 Continuous Continuous 1 s transient, square wave mV mV A A V A mA mF % % See Note 1 See Note 1 Over sample, line, load, temperature & life 20MHz bandwidth; see Note 2 100% Load 100% Load Subject to thermal derating Output Voltage 10% Low Negative current drawn from output Negative current drawn from output Nominal Vout at 100% load (resistive load) Figures 1 - 2 Figures 1 - 2 Doc.# 005-0006328 Rev. D 07/16/14 Page 4 Input: 18-36 V Output: 12V Current: 25A Package: Quarter-brick Technical Specifications PQ24120QEx25 Electrical Characteristics (continued) Ta = 25 °C, airflow rate = 300 LFM, Vin = 24V dc 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 Notes & Conditions DYNAMIC CHARACTERISTICS Output Voltage during Load Current Transient Step Change in Output Current (0.1A/µs) 400 mV 50% to 75% to 50% Iout max Step Change in Output Current (5A/µs) 350 mV 50% to 75% to 50% Iout max Settling time 0.1 ms To within 1% Vout nom Turn-On Transient Turn-On Time 35 ms Full load, Vout=90% nom; Figures 9 & 10 Output Voltage Overshoot 2 % Maximum Output Capacitance ISOLATION CHARACTERISTICS Isolation Voltage (dielectric strength) 2250 V See Absolute Maximum Ratings Isolation Resistance 30 MΩ Isolation Capacitance (input to output) 1000 pF See Note 3 TEMPERATURE LIMITS FOR POWER DERATING CURVES Semiconductor Junction Temperature 125 °C Package rated to 150°C Board Temperature 125 °C UL rated max operating temp 130°C Transformer Temperature 125 °C FEATURE CHARACTERISTICS Switching Frequency Regulation Stage 230 240 250 kHz Switching Frequency Isolation Stage 115 120 125 kHz ON/OFF Control (Option P) Off-State Voltage -2.0 0.8 V On-State Voltage 2.4 9.0 ON/OFF Control (Option N) Off-State Voltage 2.4 9.0 V On-State Voltage -2.0 0.8 ON/OFF Control (Either Option) Application notes; Figure A Pull-Up Voltage 4.75 5.00 5.25 V Pull-Up Resistance 20 kΩ Output Voltage Trim Range -50 10 % Measured across Pins 8 & 4; Figure B Output Over-Voltage Protection 113 118 123 % Over Full Temperature Range; % of nominial Vout Over-Temperature Shutdown 120 °C Average PCB Temperature Over-Temperature Shutdown Restart Hysteresis 10 °C RELIABILITY CHARACTERISTICS Calculated MTBF (Telcordia) SR-332, Issue 2 3.5 106 Hrs. TR-NWT-000332; 80% load, 300LFM, 40°C Ta Calculated MTBF (MIL-217) MIL-HDBK-217F 2.7 106 Hrs. MIL-HDBK-217F; 80% load, 300LFM, 40°C Ta Field Demonstrated MTBF 106 Hrs. See our website for details Note 1: Line and load regulation is limited by duty cycle quantization and does not indicate a shift in the internal voltage reference. Note 2: For applications requiring reduced output voltage ripple and noise, consult SynQor applications support (e-mail: [email protected]) Note 3: Higher values of isolation capacitance can be added external to the module. Product # PQ24120QEx25 Phone 1-888-567-9596 www.synqor.com Doc.# 005-0006328 Rev. D 07/16/14 Page 5 Input: 18-36 V Output: 12V Current: 25A Package: Quarter-brick Technical Specifications Standards Compliance & Qualification Testing Parameter Notes & Conditions STANDARDS COMPLIANCE UL 60950-1/R2011-12 Basic insulation EN60950-1/A2:2013 CAN/CSA-C22.2 No. 60950-1/A1:2011 Note: An external input fuse must always be used to meet these safety requirements. Contact SynQor for official safety certificates on new releases or download from the SynQor website. Parameter QUALIFICATION TESTING Life Test Vibration Mechanical Shock Temperature Cycling Power/Thermal Cycling Design Marginality Humidity Solderability Product # PQ24120QEx25 # Units 32 5 5 10 5 5 5 15 pins Phone 1-888-567-9596 Test Conditions 95% rated Vin and load, units at derating point, 1000 hours 10-55 Hz sweep, 0.060" total excursion, 1 min./sweep, 120 sweeps for 3 axis 100g minimum, 2 drops in x, y and 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, 95% RH, 1000 hours, continuous Vin applied except 5 min/day MIL-STD-883, method 2003 www.synqor.com Doc.# 005-0006328 Rev. D 07/16/14 Page 6 Input: 18-36 V Output: 12V Current: 25A Package: Quarter-brick Technical Figures 95 95 90 90 85 85 Efficiency (%) 100 Efficiency (%) 100 80 75 70 60 75 24 Vin 60 5 10 15 20 40º C 55º C 65 18 Vin 0 25º C 70 36 Vin 65 80 25 100 300 400 Air Flow (LFM) Load Current (A) Figure 1: Efficiency at nominal output voltage vs. load current for minimum, nominal, and maximum input voltage at 25°C. 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). 25 25 20 20 Power Dissipation (W) Power Dissipation (W) 200 15 10 36 Vin 5 15 10 25º C 5 40º C 24 Vin 55º C 18 Vin 0 0 0 5 10 15 20 25 Load Current (A) 100 200 300 400 Air Flow (LFM) 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). 25 Iout (A) 20 15 10 400 LFM (2.0 m/s) 300 LFM (1.5 m/s) 5 200 LFM (1.0 m/s) 100 LFM (0.5 m/s) 0 25 40 55 70 Semiconductor junction temperature is within 1°C of surface temperature 85 Ambient Air Temperature (ºC) Figure 5: Thermal Derating (max output current vs. ambient air temperature) for airflow rates of 100 LFM through 400 LFM with air flowing from pin 3 to pin 1 (nominal input voltage). Product # PQ24120QEx25 Phone 1-888-567-9596 Figure 6: Thermal Image of converter at 19 amp load current (228W) with 55°C air flowing at the rate of 200 LFM. Air is flowing from pin 3 to pin 1 (nominal input voltage). www.synqor.com Doc.# 005-0006328 Rev. D 07/16/14 Page 7 Input: 18-36 V Output: 12V Current: 25A Package: Quarter-brick Technical Figures 25 Iout (A) 20 15 10 400 LFM (2.0 m/s) 300 LFM (1.5 m/s) 5 200 LFM (1.0 m/s) 100 LFM (0.5 m/s) 0 25 40 55 70 85 Ambient Air Temperature (ºC) Figure 7: Thermal Derating (max output current vs. ambient air temperature) for airflow rates of 100 LFM through 400 LFM with air flowing lenghtwise from input to output (nominal input voltage). Figure 8: Thermal Image of converter at 18.4 amp load current (221W) with 55°C air flowing at the rate of 200 LFM. Air is flowing across the converter from input to output (nominal input voltage). Figure 9: Turn-on Transient at full load (resistive load) (10 ms/div). Input voltage pre-applied. Top Trace: Vout (5V/div). Bottom Trace: ON/OFF input(5V/ div) Figure 10: Turn-on Transient at zero load (10 ms/div). Top Trace: Vout (5V/ div). Bottom Trace: 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: 100µF electrolytic output capacitance. Top trace: Vout (500mV/div). Bottom trace: Iout (10A/div). Figure 12: Output Voltage Response to Step-Change in Load Current (50%75%-50% of Iout(max): dI/dt = 5A/µs). Load cap: 330µF electrolytic output capacitance. Top trace: Vout (500mV/div). Bottom trace: Iout (10A/div). Product # PQ24120QEx25 Phone 1-888-567-9596 www.synqor.com Doc.# 005-0006328 Rev. D 07/16/14 Page 8 Input: 18-36 V Output: 12V Current: 25A Package: Quarter-brick Technical Figures Input Reflected Ripple Current Output Voltage Ripple Input Terminal Ripple Current source impedance iS iC DC-DC Converter VOUT VSOURCE electrolytic capacitor ceramic 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 4.7µH source impedance and 220µF electrolytic capacitor (Ch.1 500mA/div). (See Figure 13). Figure 15: Input Reflected Ripple Current, is, through a 4.7 µH source inductor at nominal input voltage and rated load current (5 mA/div). (See Figure 13). Figure 16: Output Ripple at nominal input voltage and rated load current (50 mV/div). Load capacitance: one 1.0µF ceramic capacitor and one 100µF electrolytic capacitor. Bandwidth: 20 MHz. (See Figure 13). 16 14 Output Voltage (V) 12 10 8 6 18Vin 4 24 Vin 2 36 Vin 0 0 5 10 15 20 25 Load Current (A) 30 35 40 Figure 17: Output I-V Characteristics (output voltage vs load current) showing typical current limit curves and converter shutdown points. Product # PQ24120QEx25 Phone 1-888-567-9596 Figure 18: Output Short Load Current (20A/div) as a function of time when the converter attempts to turn on into a 1 mΩ short circuit. Top trace (200ms/div) is an expansion of the on-time portion of the bottom trace. www.synqor.com Doc.# 005-0006328 Rev. D 07/16/14 Page 9 Input: 18-36 V Output: 12V Current: 25A Package: Quarter-brick Applications Section BASIC OPERATION AND FEATURES CONTROL FEATURES This converter series uses a two-stage power conversion topology. The first stage 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 stepdown 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(-). 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 on-state resistance, dissipate significantly less energy than Schottky diodes, enabling the converter to achieve high efficiency. Dissipation throughout the converter is so low that it does not require a heatsink for operation in many applications; however, adding a heatsink provides improved thermal derating performance in extreme situations. To further withstand harsh environments and thermally demanding applications, certain models are available baseplated or totally encased. See Ordering Information page for available thermal design options. SynQor quarter-brick converters use the industry standard footprint and pin-out. ON/OFF Vin(_) Vin(_) Remote Enable Circuit ON/OFF ON/OFF Negative Logic (Permanently Enabled) 5V ON/OFF TTL/ CMOS Vin(_) Open Collector Enable Circuit REMOTE SENSE Pins 7(+) and 5(-): The SENSE(+) and SENSE(-) inputs correct for voltage drops along the conductors that connect the converter’s output pins to the load. Pin 7 should connect to Vout(+) and Pin 5 should connect to Vout() at the point on the board where regulation is desired. If these connections are not made, the converter will deliver an output voltage that is slightly higher than its specified value. 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. SynQor uses industry standard trim equations. To decrease the output voltage, the user should connect a resistor between Pin 6 (TRIM) and Pin 5 (SENSE(-) input). For a desired decrease of the nominal output voltage, the value of the resistor should be: Positive Logic (Permanently Enabled) Rtrim-down = where ON/OFF Vin(_) Vin(_) In negative logic versions, the ON/OFF signal is active low (meaning that a low voltage turns the converter on). In positive logic versions, the ON/OFF input is active high (meaning that a high voltage turns the converter on). Fig A details possible circuits for driving the ON/ OFF pin. See Ordering Information page for available enable logics. Direct Logic Drive ( 511% – 10.22 Δ% ) kΩ Vnominal – Vdesired × 100% Vnominal To increase the output voltage, the user should connect a resistor between Pin 6 (TRIM) and Pin 7 (SENSE(+) input). For a desired increase of the nominal output voltage, the value of the resistor should be: Δ% = Rtrim-up = 5.11 Figure A: Various Circuits for Driving the ON/OFF Pin. [ | ( | Vnominal 1.225 –2 ) × Vdesired + Vnominal Vdesired – Vnominal ] kΩ The Trim Graph in Figure B shows 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. 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. Product # PQ24120QEx25 Phone 1-888-567-9596 www.synqor.com Doc.# 005-0006328 Rev. D 07/16/14 Page 10 Input: 18-36 V Output: 12V Current: 25A Package: Quarter-brick Applications Section It is not necessary for the user to add capacitance at the TRIM pin. The node is internally filtered to eliminate noise. 100,000.0 Trim Resistance (kOhms) 10,000.0 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. 1,000.0 100.0 10.0 1.0 0.1 0.0 0 5 10 15 20 25 % increase Vout 30 35 40 45 50 % decrease Vout Figure B: Trim Graph. PROTECTION FEATURES Input Under-Voltage Lockout (UVLO): The converter is designed to turn off when the input voltage is too low, helping to avoid an input system instability problem, which is described in more detail in the application note titled “Input System Instability” on the SynQor website. When the input is rising, it must exceed the typical “Turn-On Voltage Threshold”* before the converter will turn on. Once the converter is on, the input must fall below the typical "Turn-Off Voltage Threshold"* before the converter will turn off. Output Current Limit (OCP): If the output current exceeds the “Output DC Current Limit Inception” value*, then a fast linear current limit controller will reduce the output voltage to maintain a constant output current. If as a result, the output voltage falls below the “Output DC Current Limit Shutdown Voltage”* for more than 50 ms, then the unit will enter into hiccup mode, with a 500 ms off-time. The unit will then automatically attempt to restart. Back-Drive Current Limit: If there is negative output current of a magnitude larger than the “Back-Drive Current Limit while Enabled” specification*, then a fast back-drive limit controller will increase the output voltage to maintain a constant output current. If this results in the output voltage exceeding the “Output OverVoltage Protection” threshold*, then the unit will shut down. Output Over-Voltage Limit (OVP): 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 500 ms the converter will automatically restart for all but the S Feature Set option, which is latching and will not restart until input power is cycled or the ON/OFF input is toggled. During an output over-voltage condition, the converter's LED will illuminate. For units with latching OVP (S Feature Set), once the over-voltage condition has been removed the LED will flash steadily until the input power or the ON/OFF input is toggled. Over-Temperature Shutdown (OTP): A thermister 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 “OverTemperature 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”*. Startup Inhibit Period: The Startup Inhibit Period ensures that the converter will remain off for approximately 500 ms when it is shut down due to a fault. This generates a 2 Hz “hiccup mode,” preventing the converter from overheating. There are multiple ways the converter can be shut down, initiating a Startup Inhibit Period: • • • • Output Over-Voltage Protection Current Limit Short Circuit Protection Disabling via ON/OFF input (excluding PQ60120QE & PQ60120QZ) * See Electrical Characteristics section. Product # PQ24120QEx25 Phone 1-888-567-9596 www.synqor.com Doc.# 005-0006328 Rev. D 07/16/14 Page 11 Input: 18-36 V Output: 12V Current: 25A Package: Quarter-brick Applications Section 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 website which provides an understanding of why this instability arises, and shows the preferred solution for correcting it. Application Circuits: A typical circuit diagram, Figure C below details the input filtering and voltage trimming. Input Filtering and External Input Capacitance: Figure D below shows 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 Characteristics section of the Electrical Specifications. More detailed information is available in the application note titled “EMI Characteristics” on the SynQor website. Output Filtering and External Output Capacitance: The internal output filter components are shown in Figure D below. This filter dramatically reduces output voltage ripple. Some minimum external output capacitance is required, as specified in the Output Characteristics area of the Electrical Characteristics section. No damage will occur without this capacitor connected, but peak output voltage ripple will be much higher. Thermal Considerations: For baseplated and encased versions, the max operating baseplate temperature, TB, is 100 ºC. Refer to the Thermal Derating Curves in the Technical Figures section to see the available output current at baseplate temperatures below 100 ºC. A power derating curve can be calculated for any heatsink that is attached to the base-plate of the converter. It is only necessary to determine the thermal resistance, RTHBA, of the chosen heatsink between the baseplate and the ambient air for a given airflow rate. This information is usually available from the heatsink vendor. The following formula can the be used to determine the maximum power the converter can dissipate for a given thermal condition if its base-plate is to be no higher than 100 ºC. Pdiss max Vin 100 ºC - TA RTHBA This value of maximum power dissipation can then be used in conjunction with the data shown in the Power Dissipation Curves in the Technical Figures section to determine the maximum load current (and power) that the converter can deliver in the given thermal condition. For convenience, Thermal Derating Curves are provided in the Technical Figures section. Vin(+) Vout(+) Vsense(+) Electrolytic Capacitor External Input Filter = ON/OFF Trim Vsense(_) Vin(_) Rtrim-up or Rtrim-down Cload Iload Vout(_) Figure C: Typical Application Circuit (negative logic unit, permanently enabled). Lin Vin(+) Vout(+) C1 C2 Regulation Stage Current Sense Isolation Stage Vin(_) Vout(-) Figure D: Internal Input and Output Filter Diagram (component values listed in Electrical Characteristics section). Product # PQ24120QEx25 Phone 1-888-567-9596 www.synqor.com Doc.# 005-0006328 Rev. D 07/16/14 Page 12 Technical Specification PQ24120QEx25 Ordering Information Part Numbering System Ordering Information The part numbering system for SynQor’s 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 characters for options. Add “-G” to the model number for 6/6 RoHS compliance. PQ 2 4 1 2 0 Q E B 2 5 N R A - G 6/6 RoHS Options (see Ordering Information) Model Number Input Voltage PQ24120QEw25xyz-G 18-36 V Output Voltage 12V Max Output Current 25A Output Current Thermal Design The following options must be included in place of the w x y z spaces in the model numbers listed above. Performance Level Options Description: w x y z Thermal Design Enable Logic Pin Style Package Size Output Voltage A - Open Frame B - Baseplated Input Voltage N - Negative P - Positive Product Family The first 12 characters comprise the base part number and the last 3 characters indicate available options. The “-G” suffix indicates 6/6 RoHS compliance. K - 0.110" N - 0.145" R - 0.180" Y - 0.250" Feature Set A - Standard Not all combinations make valid part numbers, please contact SynQor for availability. See the Product Summary web page for more options. Application Notes A variety of application notes and technical white papers can be downloaded in pdf format from our website. RoHS Compliance: The EU led RoHS (Restriction of Hazardous Substances) Directive bans the use of Lead, Cadmium, Hexavalent Chromium, Mercury, Polybrominated Biphenyls (PBB), and Polybrominated Diphenyl Ether (PBDE) in Electrical and Electronic Equipment. This SynQor product is 6/6 RoHS compliant. For more information please refer to SynQor’s RoHS addendum available at our RoHS Compliance / Lead Free Initiative web page or e-mail us at [email protected]. PATENTS SynQor holds the following U.S. patents, one or more of which apply to each product listed in this document. Additional patent applications may be pending or filed in the future. Contact SynQor for further information and to order: Phone: Toll Free: Fax: E-mail: Web: Address: Product # PQ24120QEx25 978-849-0600 888-567-9596 978-849-0602 [email protected] www.synqor.com 155 Swanson Road Boxborough, MA 01719 USA Phone 1-888-567-9596 5,999,417 6,222,742 6,545,890 6,577,109 6,594,159 6,731,520 6,894,468 6,896,526 6,927,987 7,050,309 7,072,190 7,085,146 7,119,524 7,269,034 7,272,021 7,272,023 7,558,083 7,564,702 7,765,687 7,787,261 8,023,290 8,149,597 8,493,751 8,644,027 Warranty SynQor offers a three (3) year limited warranty. Complete warranty information is listed on our website 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. www.synqor.com Doc.# 005-0006328 Rev. D 07/16/14 Page 13