Data Sheet August 2000 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Features The FW250C1 and FW300C1 Power Modules use advanced, surface-mount technology and deliver high-quality, compact, dc-dc conversion at an economical price. Applications ■ Size: 61.0 mm x 116.8 mm x 13.5 mm (2.40 in. x 4.60 in. x 0.53 in.) ■ Wide input voltage range ■ High efficiency: 87% typical ■ Parallel operation with load sharing ■ Output voltage set-point adjustment (trim) ■ Thermal protection ■ Synchronization ■ Power good signal ■ Current monitor ■ Output overvoltage and overcurrent protection ■ Constant frequency ■ Case ground pin ■ Input-to-output isolation ■ Redundant and distributed power architectures ■ Remote sense ■ Computer equipment ■ Remote on/off Communications equipment ■ ■ Short-circuit protection ■ ISO* 9001 Certified manufacturing facilities ■ Options ■ Heat sink available for extended operation ■ UL †1950 Recognized, CSA ‡ C22.2 No. 950-95 Certified, and VDE § 0805 (EN60950, IEC950) Licensed CE mark meets 73/23/EEC and 93/68/EEC directives** Description The FW250C1 and FW300C1 Power Modules are dc-dc converters that operate over an input voltage range of 36 Vdc to 75 Vdc and provide a precisely regulated dc output. The outputs are fully isolated from the inputs, allowing versatile polarity configurations and grounding connections. The modules have maximum power ratings from 250 W to 300 W at a typical full-load efficiency of 87%. Two or more modules may be paralleled with forced load sharing for redundant or enhanced power applications. The package, which mounts on a printed-circuit board, accommodates a heat sink for high-temperature applications. * ISO is a registered trademark of the International Organization for Standardization. † UL is a registered trademark of Underwriters Laboratories, Inc. ‡ CSA is a registered trademark of Canadian Standards Assn. § VDE is a trademark of Verband Deutscher Elektrotechniker e.V. ** This product is intended for integration into end-use equipment. All the required procedures for CE marking of end-use equipment should be followed. (The CE mark is placed on selected products.) FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Data Sheet August 2000 Absolute Maximum Ratings Stresses in excess of the absolute maximum ratings can cause permanent damage to the device. These are absolute stress ratings only. Functional operation of the device is not implied at these or any other conditions in excess of those given in the operations sections of the data sheet. Exposure to absolute maximum ratings for extended periods can adversely affect device reliability. Parameter Input Voltage: Continuous Transient (100 ms) Symbol Min Max Unit VI VI, trans — — 80 100 Vdc V I/O Isolation Voltage — — 1500 Vdc Operating Case Temperature (See Thermal Considerations section and Figure 18.) TC –40 100 °C Storage Temperature Tstg –55 125 °C Electrical Specifications Unless otherwise indicated, specifications apply over all operating input voltage, resistive load, and temperature conditions. Table 1. Input Specifications Parameter Symbol Min Typ Max Unit VI 36 48 75 Vdc II, max II, max — — — — 10 12 A A Inrush Transient i2t — — 2.0 A2s Input Reflected-ripple Current, Peak-to-peak (5 Hz to 20 MHz, 12 µH source impedance; see Figure 8.) II — 10 — mAp-p Input Ripple Rejection (120 Hz) — — 60 — dB Operating Input Voltage Maximum Input Current (VI = 0 V to 75 V): FW250C1 FW300C1 Fusing Considerations CAUTION: This power module is not internally fused. An input line fuse must always be used. This encapsulated power module can be used in a wide variety of applications, ranging from simple stand-alone operation to an integrated part of a sophisticated power architecture. To preserve maximum flexibility, internal fusing is not included; however, to achieve maximum safety and system protection, always use an input line fuse. The safety agencies require a normal-blow fuse with a maximum rating of 20 A (see Safety Considerations section). Based on the information provided in this data sheet on inrush energy and maximum dc input current, the same type of fuse with a lower rating can be used. Refer to the fuse manufacturer’s data for further information. 2 Lucent Technologies Inc. Data Sheet August 2000 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Electrical Specifications (continued) Table 2. Output Specifications Parameter Symbol Min Typ Max Unit VO, set 14.77 15.0 15.23 Vdc VO 14.55 — 15.45 Vdc Output Regulation: Line (VI = 36 V to 75 V) Load (IO = IO, min to IO, max) Temperature (T C = –40 °C to +100 °C) — — — — — — 0.01 0.05 50 0.1 0.2 100 %VO %VO mV Output Ripple and Noise Voltage (See Figure 9.): RMS Peak-to-peak (5 Hz to 20 MHz) — — — — — — 60 150 mVrms mVp-p External Load Capacitance: FW250C1 FW300C1 — — 0 0 — — * * µF µF Output Current (At IO < IO, min, the modules may exceed output ripple specifications.): FW250C1 FW300C1 IO IO 0.3 0.3 — — 16.7 20 A A IO, cli 103 — 130† % IO, max — — — 150 % IO, max Efficiency (VI = 48 V; IO = IO, max; TC = 25 °C; see Figure 10.): FW250C1 FW300C1 η η — — 87 87 — — % % Switching Frequency — — 475 — kHz — — — — 750 200 — — mV µs — — — — 750 200 — — mV µs Output Voltage Set Point (VI = 48 V; IO = IO, max; TC = 25 °C) Output Voltage (Over all operating input voltage, resistive load, and temperature conditions until end of life; see Figure 10 and Feature Descriptions.) Output Current-limit Inception (VO = 90% of VO, set; see Feature Descriptions.) Output Short-circuit Current (VO = 1.0 V; indefinite duration, no hiccup mode) Dynamic Response (∆IO/∆t = 1 A/10 µs, VI = 48 V, TC = 25 °C; tested with a 10 µF aluminum and a 1.0 µF ceramic capacitor across the load; see Figures 5 and 6.): Load Change from IO = 50% to 75% of IO, max: Peak Deviation Settling Time (VO < 10% of peak deviation) Load Change from IO = 50% to 25% of IO, max: Peak Deviation Settling Time (VO < 10% of peak deviation) * Consult your sales representative or the factory. † These are manufacturing test limits. In some situations, results may differ. Lucent Technologies Inc. 3 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Data Sheet August 2000 Electrical Specifications (continued) Table 3. Isolation Specifications Parameter Min Typ Max Unit Isolation Capacitance — 1700 — pF Isolation Resistance 10 — — MΩ Typ Max General Specifications Parameter Min Calculated MTBF (IO = 80% of IO, max; TC = 40 °C) 1,487,000 Weight — — Unit hours 200 (7) g (oz.) Feature Specifications Unless otherwise indicated, specifications apply over all operating input voltage, resistive load, and temperature conditions. See Feature Descriptions for further information. Table 4. Feature Specifications Parameter Symbol Min Typ Max Unit Von/off Ion/off 0 — — — 1.2 1.0 V mA Von/off Ion/off — — — — — — 30 15 50 50 V µA ms — — 0 5 %VO, set Output Voltage Adjustment (See Feature Descriptions.): Output Voltage Remote-sense Range Output Voltage Set-point Adjustment Range (trim) — — — 60 — — 0.5 100 V %VO, nom Output Overvoltage Protection — 17.0* — 20.0* V IO, mon — 0.25 — V/A Remote On/Off Signal Interface (VI = 0 V to 75 V; open collector or equivalent compatible; signal referenced to VI (–) terminal; see Figure 11 and Feature Descriptions.): Logic Low—Module On Logic High—Module Off Logic Low: At Ion/off = 1.0 mA At Von/off = 0.0 V Logic High: At Ion/off = 0.0 µA Leakage Current Turn-on Time (IO = 80% of IO, max; VO within ±1% of steady state) Output Voltage Overshoot Output Current Monitor (IO = IO, max, TC = 70 °C) * These are manufacturing test limits. In some situations, results may differ. 4 Lucent Technologies Inc. Data Sheet August 2000 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Feature Specifications (continued) Table 5. Feature Specifications (continued) Parameter Symbol Min Typ Max Unit Synchronization: Clock Amplitude Clock Pulse Width Fan-out Capture Frequency Range — — — — 4.00 0.4 — 425 — — — — 5.00 — 1 575 V µs — kHz Overtemperature Protection (See Figure 18.) TC — 105 — °C Forced Load Share Accuracy — — 10 — %IO, rated Rpwr/good Ipwr/good Rpwr/good Vpwr/good — — 1 — — — — — 100 1 — 40 Ω mA MΩ V Power Good Signal Interface (See Feature Descriptions.): Low Impedance—Module Operating High Impedance—Module Off Solder, Cleaning, and Drying Considerations Post solder cleaning is usually the final circuit-board assembly process prior to electrical testing. The result of inadequate circuit-board cleaning and drying can affect both the reliability of a power module and the testability of the finished circuit-board assembly. For guidance on appropriate soldering, cleaning, and drying procedures, refer to Lucent Technologies Board-Mounted Power Modules Soldering and Cleaning Application Note (AP97-021EPS). Lucent Technologies Inc. 5 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Data Sheet August 2000 Characteristic Curves The following figures provide typical characteristics for the power modules. 12 90 88 IOUT = 20 A 86 IOUT = 10 A 8 EFFICIENCY, η (%) INPUT CURRENT, II (A) 10 IOUT = 2 A 6 4 84 82 80 76 2 74 0 72 70 0 10 20 30 40 50 60 70 80 VI = 36 V V I = 54 V V I = 72 V 78 0 INPUT VOLTAGE, VI (V) 2 4 6 8 10 12 14 16 18 20 OUTPUT CURRENT, IO (A) 8-2141 (F) Figure 1. Typical FW300C1 Input Characteristics at Room Temperature, IO = Full Load 8-2143 (F) Figure 3. Typical FW300C1 Efficiency vs. Output Current at Room Temperature 14 VI = 36 V 12 10 VI = 36 V 8 V I = 46 V V I = 75 V 6 4 2 0 0 5 10 15 20 25 OUTPUT VOLTAGE, VO (V) (10 mV/div) OUTPUT VOLTAGE, VO (V) 16 V I = 48 V V I = 72 V OUTPUT CURRENT, IO (A) 8-2142 (F) Figure 2. Typical FW300C1 Output Characteristics at Room Temperature TIME, t (200 ns/div) 8-2144 (F) Note: See Figure 10 for test conditions. Figure 4. Typical FW300C1 Output Ripple Voltage at Room Temperature and 20 A Output 6 Lucent Technologies Inc. Data Sheet August 2000 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W OUTPUT VOLTAGE, VO (V) (5 V/div) OUTPUT VOLTAGE, VO (V) (500 mV/div) REMOTE ON/OFF, VON/OFF (V) Characteristic Curves (continued) OUTPUT CURRENT, IO (V) (5 Adiv) 15 V TIME, t (5 ms/div) 8-2147 (F) TIME, t (50 µs/div) 8-2145 (F) Note: Tested with a 10 µF aluminum and a 1.0 µF ceramic capacitor across the load. OUTPUT CURRENT, IO (A) (5 A/div) OUTPUT VOLTAGE, VO (V) (500 mV/div) Figure 5. Typical FW300C1 Transient Response to Step Decrease in Load from 50% to 25% of Full Load at Room Temperature and 48 V Input (Waveform Averaged to Eliminate Ripple Component.) Figure 7. Typical FW300C1 Start-Up Transient at Room Temperature, 48 V Input, and Full Load TIME, t (50 µs/div) 8-2146 (F) Note: Tested with a 10 µF aluminum and a 1.0 µF ceramic capacitor across the load. Figure 6. Typical FW300C1 Transient Response to Step Increase in Load from 50% to 75% of Full Load at Room Temperature and 48 V Input (Waveform Averaged to Eliminate Ripple Component.) Lucent Technologies Inc. 7 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Test Configurations Data Sheet August 2000 Design Considerations Input Source Impedance TO OSCILLOSCOPE LTEST VI (+) 12 µH Cs 220 µF ESR < 0.1 Ω @ 20 °C, 100 kHz BATTERY 100 µF ESR < 0.3 Ω @ 100 kHz VI (–) The power module should be connected to a low ac-impedance input source. Highly inductive source impedances can affect the stability of the power module. For the test configuration in Figure 8, a 100 µF electrolytic capacitor (ESR < 0.3 ¾ at 100 kHz) mounted close to the power module helps ensure stability of the unit. For other highly inductive source impedances, consult the factory for further application guidelines. 8-203 (F).o Note: Measure input reflected-ripple current with a simulated source inductance (LTEST) of 12 µH. Capacitor CS offsets possible battery impedance. Measure current as shown above. Figure 8. Input Reflected-Ripple Test Setup COPPERSTRIP VO (+) 1.0µF RESISTIVE LOAD 10.0µF SCOPE VO (+) Safety Considerations For safety-agency approval of the system in which the power module is used, the power module must be installed in compliance with the spacing and separation requirements of the end-use safety agency standard, i.e., UL1950, CSA C22.2 No. 950-95, and VDE 0805 (EN60950, IEC950). If the input source is non-SELV (ELV or a hazardous voltage greater than 60 Vdc and less than or equal to 75 Vdc), for the module’s output to be considered meeting the requirements of safety extra-low voltage (SELV), all of the following must be true: ■ Note: Use a 0.1 µF ceramic capacitor and a 10 µF aluminum or tantalum capacitor. Scope measurement should be made using a BNC socket. Position the load between 50 mm and 76 mm (2 in. and 3 in.) from the module. The input source is to be provided with reinforced insulation from any hazardous voltages, including the ac mains. ■ Figure 9. Peak-to-Peak Output Noise Measurement Test Setup One VI pin and one VO pin are to be grounded, or both the input and output pins are to be kept floating. ■ The input pins of the module are not operator accessible. ■ Another SELV reliability test is conducted on the whole system, as required by the safety agencies, on the combination of supply source and the subject module to verify that under a single fault, hazardous voltages do not appear at the module’s output. 8-513 (F).m SENSE(+) SENSE(–) SUPPLY VI(+) VO(+) VI(–) VO (–) IO II CONTACT RESISTANCE LOAD CONTACT AND DISTRIBUTION LOSSES 8-683 (F).f Note: All measurements are taken at the module terminals. When socketing, place Kelvin connections at module terminals to avoid measurement errors due to socket contact resistance. [ V O(+ ) – VO( – ) ]IO η = -------------------------------------------------- x 100 [ VI( + ) – VI( – )] II % Note: Do not ground either of the input pins of the module without grounding one of the output pins. This may allow a non-SELV voltage to appear between the output pin and ground. The power module has extra-low voltage (ELV) outputs when all inputs are ELV. The input to these units is to be provided with a maximum 20 A normal-blow fuse in the ungrounded lead. Figure 10. Output Voltage and Efficiency Measurement Test Setup 8 Lucent Technologies Inc. Data Sheet August 2000 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Feature Descriptions Remote Sense Overcurrent Protection Remote sense minimizes the effects of distribution losses by regulating the voltage at the remote-sense connections. The voltage between the remote-sense pins and the output terminals must not exceed the output voltage sense range given in the Feature Specifications table, i.e.: To provide protection in a fault (output overload) condition, the unit is equipped with internal current-limiting circuitry and can endure current limiting for an unlimited duration. At the point of current-limit inception, the unit shifts from voltage control to current control. If the output voltage is pulled very low during a severe fault, the current-limit circuit can exhibit either foldback or tailout characteristics (output-current decrease or increase). The unit operates normally once the output current is brought back into its specified range. Remote On/Off To turn the power module on and off, the user must supply a switch to control the voltage between the on/off terminal and the VI(–) terminal (Von/off). The switch can be an open collector or equivalent (see Figure 11). A logic low is Von/off = 0 V to 1.2 V, during which the module is on. The maximum Ion/off during a logic low is 1 mA. The switch should maintain a logic-low voltage while sinking 1 mA. During a logic high, the maximum Von/off generated by the power module is 15 V. The maximum allowable leakage current of the switch at Von/off = 15 V is 50 µA. If not using the remote on/off feature, short the ON/OFF pin to VI(–). SENSE(+) CASE SENSE(–) Ion/off + Von/off – [VO(+) – VO(–)] – [SENSE(+) – SENSE(–)] ≤ 0.5 V The voltage between the VO(+) and VO(–) terminals must not exceed the minimum value indicated in the output overvoltage shutdown section of the Feature Specifications table. This limit includes any increase in voltage due to remote-sense compensation and output voltage set-point adjustment (trim), see Figure 12. If not using the remote-sense feature to regulate the output at the point of load, connect SENSE(+) to VO(+) and SENSE(–) to VO(–) at the module. Although the output voltage can be increased by both the remote sense and by the trim, the maximum increase for the output voltage is not the sum of both. The maximum increase is the larger of either the remote sense or the trim. Consult the factory if you need to increase the output voltage more than the above limitation. 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. VO(+) ON/OFF VI(+) SENSE(+) VO(–) V I(–) SENSE(–) VI(–) VO(–) VI(+) VO(+) 8-580 (F).d SUPPLY Figure 11. Remote On/Off Implementation IO II CONTACT RESISTANCE LOAD CONTACT AND DISTRIBUTION LOSSES 8-651 (F).e Figure 12. Effective Circuit Configuration for Single-Module Remote-Sense Operation Lucent Technologies Inc. 9 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Feature Descriptions (continued) Output Voltage Set-Point Adjustment (Trim) Output voltage trim allows the user to increase or decrease the output voltage set point of a module. This is accomplished by connecting an external resistor between the TRIM pin and either the SENSE(+) or SENSE(–) pins. The trim resistor should be positioned close to the module. 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. VI(+) If not using the trim feature, leave the TRIM pin open. ON/OFF With an external resistor between the TRIM and SENSE(–) pins (Radj-down), the output voltage set point (VO, adj) decreases (see Figure 13). The following equation determines the required external-resistor value to obtain a percentage output voltage change of ∆%. CASE VO(+) SENSE(+) TRIM RLOAD Radj-down VI(–) SENSE(–) VO(–) kΩ The test results for this configuration are displayed in Figure 14. This figure applies to all output voltages. With an external resistor connected between the TRIM and SENSE(+) pins (Radj-up), the output voltage set point (VO, adj) increases (see Figure 15). Note: The output voltage of this module may be increased to a maximum of 0.5 V. The 0.5 V is the combination of both the remote sense and the output voltage set-point adjustment (trim). Do not exceed 15.5 V between the VO(+) and VO(–) terminals. The following equation determines the required external-resistor value to obtain a percentage output voltage change of ∆%. V O ( 100 + ∆ % ) ( 100 + 2 ∆ % ) Radj-up = --------------------------------------- – ---------------------------------- k Ω 1.225 ∆ % ∆% Only trim up to 0.5 V maximum. See note above. 8-748 (F).b Figure 13. Circuit Configuration to Decrease Output Voltage ADJUSTMENT RESISTOR VALUE (Ω) R adj-down 205 = ---------- – 2.255 ∆% Data Sheet August 2000 1M 100k 10k 1k 0 10 20 30 40 % CHANGE IN OUTPUT VOLTAGE (∆%) 8-1171 (F).g The test results for this configuration are displayed in Figure 16. For applications requiring voltage between 15 V and 24 V, consider using the FW250H1 trimmed down. Figure 14. Resistor Selection for Decreased Output Voltage Although the output voltage can be increased by both the remote sense and by the trim, the maximum increase for the output voltage is not the sum of both. The maximum increase is the larger of either the remote sense or the trim. Consult the factory if you need to increase the output voltage more than the above limitation. 10 Lucent Technologies Inc. Data Sheet August 2000 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Feature Descriptions (continued) Output Current Monitor Output Voltage Set-Point Adjustment (Trim) (continued) The CURRENT MON pin provides a dc voltage proportional to the dc output current of the module given in the Feature Specifications table. For example, on the FW250C1, the V/A ratio is set at 250 mV/A ± 10% @ 70 °C case. At a full load current of 16.7 A, the voltage on the CURRENT MON pin is 4.18 V. The current monitor signal is referenced to the SENSE(–) pin on the secondary and is supplied from a source impedance of approximately 2 kΩ . It is recommended that the CURRENT MON pin be left open when not in use, although no damage will result if the CURRENT MON pin is shorted to secondary ground. Directly driving the CURRENT MON pin with an external source will detrimentally affect operation of the module and should be avoided. VO(+) VI(+) ON/OFF SENSE(+) Radj-up TRIM CASE VI(–) RLOAD SENSE(–) VO(–) 8-715 (F).b ADJUSTMENT RESISTOR VALUE (Ω) Figure 15. Circuit Configuration to Increase Output Voltage Synchronization Any module can be synchronized to any other module or to an external clock using the SYNC IN or SYNC OUT pins. The modules are not designed to operate in a master/slave configuration; that is, if one module fails, the other modules will continue to operate. 100M 10M SYNC IN Pin This pin can be connected either to an external clock or directly to the SYNC OUT pin of another FW250x or FW300x module. 1M 100k 0 0.7 1.4 2.1 2.8 3.5 % CHANGE IN OUTPUT VOLTAGE (∆%) 8-2148 (F) Figure 16. Resistor Selection for Increased Output Voltage Output Overvoltage Protection The output voltage is monitored at the VO(+) and VO(–) pins of the module. If the voltage at these pins exceeds the value indicated in the Feature Specifications table, the module will shut down and latch off. Recovery from latched shutdown is accomplished by cycling the dc input power off for at least 1.0 second or toggling the primary referenced on/off signal for at least 1.0 second. Lucent Technologies Inc. If an external clock signal is applied to the SYNC IN pin, the signal must be a 500 kHz (±50 kHz) square wave with a 4 Vp-p amplitude. Operation outside this frequency band will detrimentally affect the performance of the module and must be avoided. If the SYNC IN pin is connected to the SYNC OUT pin of another module, the connection should be as direct as possible, and the VI(–) pins of the modules must be shorted together. Unused SYNC IN pins should be tied to VI(–). If the SYNC IN pin is unused, the module will operate from its own internal clock. 11 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Feature Descriptions (continued) Synchronization (continued) Good layout techniques should be observed for noise immunity. To implement forced load sharing, the following connections must be made: ■ The parallel pins of all units must be connected together. The paths of these connections should be as direct as possible. ■ All remote-sense pins should be connected to the power bus at the same point, i.e., connect all SENSE(+) pins to the (+) side of the power bus at the same point and all SENSE(–) pins to the (–) side of the power bus at the same point. Close proximity and directness are necessary for good noise immunity. SYNC OUT Pin This pin contains a clock signal referenced to the VI(–) pin. The frequency of this signal will equal either the module’s internal clock frequency or the frequency established by an external clock applied to the SYNC IN pin. When synchronizing several modules together, the modules can be connected in a daisy-chain fashion where the SYNC OUT pin of one module is connected to the SYNC IN pin of another module. Each module in the chain will synchronize to the frequency of the first module in the chain. To avoid loading effects, ensure that the SYNC OUT pin of any one module is connected to the SYNC IN pin of only one module. Any number of modules can be synchronized in this daisy-chain fashion. Data Sheet August 2000 When not using the parallel feature, leave the PARALLEL pin open. PARALLEL SENSE(+) SENSE(–) CASE VO(+) ON/OFF Overtemperature Protection To provide protection in a fault condition, the unit is equipped with an overtemperature shutdown circuit. The shutdown circuit will not engage unless the unit is operated above the maximum case temperature. Recovery from overtemperature shutdown is accomplished by cycling the dc input power off for at least 1.0 second or toggling the primary referenced on/off signal for at least 1.0 second. VI(+) VO(–) VI(–) PARALLEL SENSE(+) SENSE(–) CASE VO(+) ON/OFF VI(+) 8-581 (F) Forced Load Sharing (Parallel Operation) For either redundant operation or additional power requirements, the power modules can be configured for parallel operation with forced load sharing (see Figure 17). For a typical redundant configuration, Schottky diodes or an equivalent should be used to protect against short-circuit conditions. Because of the remote sense, the forward-voltage drops across the Schottky diodes do not affect the set point of the voltage applied to the load. For additional power requirements, where multiple units are used to develop combined power in excess of the rated maximum, the Schottky diodes are not needed. 12 VO(–) VI(–) Figure 17. Wiring Configuration for Redundant Parallel Operation Power Good Signal The PWR GOOD pin provides an open-drain signal (referenced to the SENSE(–) pin) that indicates the operating state of the module. A low impedance (<100 Ω) between PWR GOOD and SENSE(–) indicates that the module is operating. A high impedance (>1 MΩ) between PWR GOOD and SENSE(–) indicates that the module is off or has failed. The PWR GOOD pin can be pulled up through a resistor to an external voltage to facilitate sensing. This external voltage level must not exceed 40 V, and the current into the PWR GOOD pin during the low-impedance state should be limited to 1 mA maximum. Lucent Technologies Inc. Data Sheet August 2000 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Thermal Considerations Introduction The power modules operate in a variety of thermal environments; however, sufficient cooling should be provided to help ensure reliable operation of the unit. Heat-dissipating components inside the unit are thermally coupled to the case. Heat is removed by conduction, convection, and radiation to the surrounding environment. Proper cooling can be verified by measuring the case temperature. Peak temperature occurs at the position indicated in Figure 18. POWER DISSIPATION, PD (W) 70 4.0 m/s (800 ft./min.) 3.5 m/s (700 ft./min.) 3.0 m/s (600 ft./min.) 2.5 m/s (500 ft./min.) 2.0 m/s (400 ft./min.) 1.5 m/s (300 ft./min.) 1.0 m/s (200 ft./min.) 0.5 m/s (100 ft./min.) 60 50 40 30 20 10 0.1 m/s (20 ft./min.) NAT. CONV. 0 0 30.5 (1.20) 30 40 50 60 70 80 90 100 8-1315 (F) VO(+) VI(–) ON/OFF SYNC IN SYNC OUT 20 LOCAL AMBIENT TEMPERATURE, TA (°C) MEASURE CASE TEMPERATURE HERE VI(+) 10 Figure 19. Convection Power Derating with No Heat Sink; Airflow Along Width (Transverse) VO (–) CASE 82.6 (3.25) 8-1303 (F).f Note: Top view, measurements shown in millimeters and (inches). Pin locations are for reference only. Figure 18. Case Temperature Measurement Location The temperature at this location should not exceed 100 °C. The maximum case temperature can be limited to a lower value for extremely high reliability. The output power of the module should not exceed the rated power for the module as listed in the Ordering Information table. For additional information about these modules, refer to the Lucent Technologies Thermal Management for FCand FW-Series 250 W—300 W Board-Mounted Power Modules Technical Note (TN96-009EPS). POWER DISSIPATION, PD (W) 70 4.0 m/s (800 ft./min.) 3.5 m/s (700 ft./min.) 3.0 m/s (600 ft./min.) 2.5 m/s (500 ft./min.) 2.0 m/s (400 ft./min.) 1.5 m/s (300 ft./min.) 1.0 m/s (200 ft./min.) 0.5 m/s (100 ft./min.) 60 50 40 30 20 10 0.1 m/s (20 ft./min.) NAT. CONV. 0 0 10 20 30 40 50 60 70 80 90 100 LOCAL AMBIENT TEMPERATURE, TA (°C) 8-1314 (F) Figure 20. Convection Power Derating with No Heat Sink; Airflow Along Length (Longitudinal) Heat Transfer Without Heat Sinks Derating curves for forced-air cooling without a heat sink are shown in Figures 19 and 20. These curves can be used to determine the appropriate airflow for a given set of operating conditions. For example, if the unit with airflow along its length dissipates 20 W of heat, the correct airflow in a 40 °C environment is 1.0 m/s (200 ft./min.). Lucent Technologies Inc. 13 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Data Sheet August 2000 Thermal Considerations (continued) Heat Transfer with Heat Sinks The power modules have through-threaded, M3 x 0.5 mounting holes, which enable heat sinks or cold plates to be attached to the module. The mounting torque must not exceed 0.56 N-m (5 in.-lb.). For the screw attachment from the pin side, the recommended hole size on the customer’s PWB around the mounting holes is 0.130 ± 0.005 inches. If a larger hole is used, the mounting torque from the pin side must not exceed 0.25 N-m (2.2 in.-lbs.). Thermal derating with heat sinks is expressed by using the overall thermal resistance of the module. Total module thermal resistance (θca) is defined as the maximum case temperature rise (∆TC, max) divided by the module power dissipation (PD): (TC – TA ) T C, max θ ca = ∆-------------------- = ------------------------ PD PD The location to measure case temperature (TC) is shown in Figure 18. Case-to-ambient thermal resistance vs. airflow for various heat sink configurations is shown in Figure 21 and Figure 22. These curves were obtained by experimental testing of heat sinks, which are offered in the product catalog. 1 1/2 IN. HEAT SINK 4.0 1 IN. HEAT SINK 1/2 IN. HEAT SINK 3.5 1/4 IN. HEAT SINK 3.0 1 1/2 IN. HEAT SINK 4.0 1 IN. HEAT SINK 3.5 1/2 IN. HEAT SINK 1/4 IN. HEAT SINK 3.0 NO HEAT SINK 2.5 2.0 1.5 1.0 0.5 0.0 0 0.5 (100) 1.0 (200) 1.5 (300) 2.0 (400) 2.5 3.0 (500) (600) AIR VELOCITY, m/s (ft./min.) 8-1320 (F) Figure 22. Case-to-Ambient Thermal Resistance Curves; Longitudinal Orientation These measured resistances are from heat transfer from the sides and bottom of the module as well as the top side with the attached heat sink; therefore, the case-to-ambient thermal resistances shown are generally lower than the resistance of the heat sink by itself. The module used to collect the data in Figures 21 and 22 had a thermal-conductive dry pad between the case and the heat sink to minimize contact resistance. To choose a heat sink, determine the power dissipated as heat by the unit for the particular application. Figure 23 shows typical heat dissipation for a range of output currents and three voltages for the FW300C1. NO HEAT SINK 2.5 2.0 1.5 1.0 0.5 0.0 0 0.5 (100) 1.0 (200) 1.5 (300) 2.0 (400) 2.5 3.0 (500) (600) AIR VELOCITY, m/s (ft./min.) 8-1321 (F) Figure 21. Case-to-Ambient Thermal Resistance Curves; Transverse Orientation POWER DISSIPATION, PD (W) CASE-TO-AMBIENT THERMAL RESISTANCE, θca (°C/W) 4.5 CASE-TO-AMBIENT THERMAL RESISTANCE, θca (°C/W) 4.5 50 45 40 35 30 25 20 VI = 36 V VI = 54 V VI = 75 V 15 10 5 0 0 2 4 6 8 10 12 14 16 18 20 OUTPUT CURRENT, I O (A) 8-1743 (F) Figure 23. FW300C1 Power Dissipation vs. Output Current at 25 °C 14 Lucent Technologies Inc. Data Sheet August 2000 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Thermal Considerations (continued) Custom Heat Sinks Heat Transfer with Heat Sinks (continued) A more detailed model can be used to determine the required thermal resistance of a heat sink to provide necessary cooling. The total module resistance can be separated into a resistance from case-to-sink (θcs) and sink-to-ambient (θsa) as shown in Figure 24. Example If an 85 °C case temperature is desired, what is the minimum airflow necessary? Assume the FW300C1 module is operating at nominal line and an output current of 20 A, maximum ambient air temperature of 40 °C, and the heat sink is 1/2 inch. PD TC TS θcs Solution TA θsa 8-1304 (F).e Given: VI = 54 V IO = 20 A TA = 40 °C TC = 85 °C Heat sink = 1/2 inch Determine PD by using Figure 24: PD = 42 W Then solve the following equation: TC – TA) θ ca = (-----------------------PD ( 85 – 40 ) θ ca = ----------------------- 42 Figure 24. Resistance from Case-to-Sink and Sinkto-Ambient For a managed interface using thermal grease or foils, a value of θcs = 0.1 °C/W to 0.3 °C/W is typical. The solution for heat sink resistance is: (TC – TA ) PD θ sa = ------------------------- – θ cs This equation assumes that all dissipated power must be shed by the heat sink. Depending on the userdefined application environment, a more accurate model, including heat transfer from the sides and bottom of the module, can be used. This equation provides a conservative estimate for such instances. θ ca = 1.07 °C/W Use Figures 21 and 22 to determine air velocity for the 0.5 inch heat sink. The minimum airflow necessary for the FW250C1 module depends on heat sink fin orientation and is shown below: ■ 2.0 m/s (400 ft./min.) (oriented along width) ■ 3.0 m/s (600 ft./min.) (oriented along length) EMC Considerations For assistance with designing for EMC compliance, please refer to the FLTR100V10 data sheet (DS99-294EPS). Layout Considerations Copper paths must not be routed beneath the power module mounting inserts. For additional layout guidelines, refer to the FLTR100V10 data sheet (DS99-294EPS). Lucent Technologies Inc. 15 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Data Sheet August 2000 Outline Diagram Dimensions are in millimeters and (inches). Tolerances: x.x mm ± 0.5 mm (x.xx in. ± 0.02 in.), x.xx mm ± 0.25 mm (x.xxx in. ± 0.010 in.) Top View 116.8 (4.60) 61.0 (2.40) Side View 13.5 (0.53) SIDE LABEL* 1.57 ± 0.05 (0.062 ± 0.002) DIA SOLDER-PLATED BRASS, 11 PLACES, (VOUT–, VOUT+, VIN–, VIN+) 5.1 (0.20) MIN 1.02 ± 0.05 (0.040 ± 0.002) DIA SOLDER-PLATED BRASS, 9 PLACES Bottom View 12.7 (0.50) 7.62 (0.300) 30.48 (1.200) 50.8 (2.00) 66.04 (2.600) 2.54 (0.100) TYP CASE SYNC OUT SYNC IN 2.54 (0.100) TYP SENSE– SENSE+ TRIM PARALLEL CURRENT MON PWR GOOD 12.70 17.78 (0.500) (0.700) 22.86 (0.900) MOUNTING INSERTS M3 x 0.5 THROUGH, 4 PLACES 5.1 (0.20) 10.16 (0.400) VO– ON/OFF VI– 5.08 (0.200) 15.24 (0.600) 30.48 (1.200) 20.32 (0.800) 25.40 (1.000) 35.56 (1.400) VO+ VI+ 5.1 (0.20) 106.68 (4.200) 8-1650 (F).pg1 * Side label includes Lucent logo, product designation, safety agency markings, input/output voltage and current ratings and bar code. 16 Lucent Technologies Inc. Data Sheet August 2000 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Recommended Hole Pattern Component-side footprint. Dimensions are in millimeters and (inches). MOUNTING INSERTS 7.62 (0.300) 66.04 (2.600) 2.54 (0.100) TYP 7.62 (0.300) 7.62 (0.300) 5.1 (0.20) 30.48 (1.200) 15.24 (0.600) 20.32 (0.800) 25.40 (1.000) 5.08 (0.200) VO– PWR GOOD CURRENT MON PARALLEL TRIM SENSE+ SENSE– 10.16 (0.400) 12.7 (0.50) 2.54 (0.100) TYP CASE SYNC OUT SYNC IN ON/OFF VI– 35.56 (1.400) VO+ VI+ 12.70 (0.500) 17.78 (0.700) 22.86 (0.900) 30.48 (1.200) 50.8 (2.00) 5.1 (0.20) 106.68 (4.200) 8-1650 (F).pg2 Ordering Information Table 6. Device Codes Input Voltage Output Voltage Output Power Device Code Comcode 48 V 15 V 250 W FW250C1 107588345 48 V 15 V 300 W FW300C1 107588352 Lucent Technologies Inc. 17 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Data Sheet August 2000 Ordering Information (continued) Table 7. Device Accessories Accessory Comcode 1/4 in. transverse kit (heat sink, thermal pad, and screws) 1/4 in. longitudinal kit (heat sink, thermal pad, and screws) 1/2 in. transverse kit (heat sink, thermal pad, and screws) 1/2 in. longitudinal kit (heat sink, thermal pad, and screws) 1 in. transverse kit (heat sink, thermal pad, and screws) 1 in. longitudinal kit (heat sink, thermal pad, and screws) 1 1/2 in. transverse kit (heat sink, thermal pad, and screws) 1 1/2 in. longitudinal kit (heat sink, thermal pad, and screws) 847308335 847308327 847308350 847308343 847308376 847308368 847308392 847308384 Dimension are in millimeters and (inches). 1/4 IN. 1/4 IN. 59.94 (2.36) 1/2 IN. 115.82 (4.56) 1 IN. 1/2 IN. 1 IN. 115.82 (4.56) 1 1/2 IN. 1 1/2 IN. 60.45 (2.38) 8-2831 (F) 8-2830 (F) Figure 25. Longitudinal Heat Sink 18 Figure 26. Transverse Heat Sink Lucent Technologies Inc. Data Sheet August 2000 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Notes Lucent Technologies Inc. 19 FW250C1 and FW300C1 Power Modules: dc-dc Converters; 36 to 75 Vdc Input, 15 Vdc Output; 250 W to 300 W Data Sheet August 7, 2000 For additional information, contact your Lucent Technologies Account Manager or the following: POWER SYSTEMS UNIT: Network Products Group, Lucent Technologies Inc., 3000 Skyline Drive, Mesquite, TX 75149, USA +1-800-526-7819 (Outside U.S.A.: +1-972-284-2626, FAX +1-888-315-5182) (product-related questions or technical assistance) INTERNET: http://www.lucent.com/networks/power E-MAIL: [email protected] ASIA PACIFIC: Lucent Technologies Singapore Pte. Ltd., 750D Chai Chee Road #07-06, Chai Chee Industrial Park, Singapore 469004 Tel. (65) 240 8041, FAX (65) 240 8438 CHINA: Lucent Technologies (China) Co. Ltd., SCITECH Place No. 22 Jian Guo Man Wai Avenue, Beijing 100004, PRC Tel. (86) 10-6522 5566 ext. 4187, FAX (86) 10-6512 3694 JAPAN: Lucent Technologies Japan Ltd., Mori Building No. 21, 4-33, Roppongi 1-chome, Minato-ku, Tokyo 106-8508, Japan Tel. (81) 3 5561 5831, FAX (81) 3 5561 1616 LATIN AMERICA: Lucent Technologies Inc., Room 416, 2333 Ponce de Leon Blvd., Coral Gables, FL 33134, USA Tel. +1-305-569-4722, FAX +1-305-569-3820 EUROPE: Technical Inquiries: GERMANY: (49) 89 95086 0 (Munich), UNITED KINGDOM: (44) 1344 865 900 (Ascot), FRANCE: (33) 1 40 83 68 00 (Paris), SWEDEN: (46) 8 594 607 00 (Stockholm), FINLAND: (358) 9 4354 2800 (Helsinki), ITALY: (39) 02 6608131 (Milan), SPAIN: (34) 91 807 1441 (Madrid) Lucent Technologies Inc. reserves the right to make changes to the product(s) or information contained herein without notice. No liability is assumed as a result of their use or application. No rights under any patent accompany the sale of any such product(s) or information. Copyright © 2000 Lucent Technologies Inc. All Rights Reserved Printed in U.S.A. August 2000 DS00-157EPS (Replaces DS97-517EPS) Printed On Recycled Paper