BTCPower TM Broadband TelCom Power, Inc. Redefining “Current” Limits In Power Conversion Technical Specification S25-48-5, S25-48-5N 48Vin 5.0Vout 5A Description The S25 family of high efficiency, low power DC/DC converters offer power levels that exceed other bricks with similar footprints. They are targeted specifically at the telecommunication, industrial electronics, mobile telecommunication and distributed power markets. With a wide input voltage range of 36-75V they are available with output voltages of either 1.5, 1.8, 2.5, 3.3 or 5 Volts. All models feature an input filter, input undervoltage lockout, output overvoltage and overtemperature protection, output current limiting and short circuit protection. The fully enclosed, encapsulated construction with aluminum heat spreader design achieves very efficient heat transfer with no hot spots. The use of patented design concepts facilitate maximum power delivered with the highest efficiency up to 90%. The converters combine creative design concepts with highly derated power devices to achieve very high reliability, high performance and low cost solution to systems designers requiring maximum power in small footprints. Features • • • • • • • • • • • • • • • • • Applications • • • • • • • Telecommunications Data Communications Wireless Communications Networking Gear Servers, Switches and Data Storage Semiconductor Test Equipment Distributed Power Architecture • • • • Delivers up to 25W in 1.2” x 2.0” format High power density up to 30W/inch3 Synchronous rectification topology No airflow or heat sink required No minumum load required Low profile of only 0.35 inch High output current in small footprint 1.5V, 1.8V, 2.5V, 3.3V or 5V models Wide input operating range 36-75V -40°C to +100°C ambient operation Input undervoltage lockout Output overvoltage protection Output current limit and short circuit protection On/Off pin Output adjustment +/-10% range 1500V, 10M input-to-output isolation Enclosed construction with heat spreader for low temperature rise Enclosed six-sided metal shield construction for low EMI/RFI UL 60950 recognized, TUV EN60950 and CSA C22.2 No. 60950-00 Certified Meets conducted limits of FCC Class B and CEI IEC61204-3 Class B with external filter MTBF of 850,000 hours @ 50°C (MIL-HDBK-217F) Broadband TelCom Power, Inc. – 1719 S. Grand Avenue, Santa Ana, CA 92705 U.S.A. Tel.: 714-259-4888 • Fax: 714-259-0840 • www.btcpower.com • Email: [email protected] PS S25-48-5 Rev 3 16-1-04 BTCPower TM Technical Specification S25-48-5, S25-48-5N 48Vin 5Vout 5.0A CONVERTER SELECTION Typical @ Ta=+25°C under nominal line voltage and full load conditions. Input Output Voltage (Volts) Model Current (A) Voltage Current Efficiency 75% Load Nominal Range No load Full load (Volts) (Amps) (%) 48 36-75 0.050 0.613 5.0 5.0 90 S25-48-5 Consult factory for other output voltage configurations. Outline Information and Summary Specifications Pin Connection Pin# Single Output 1 On/Off 2 3 4 Vin Vin + Vout + 5 6 Vout Trim All dimensions are in inches [mm] All pins are dia. 0.040 [1.02] Pin material: Brass Pin finish: Gold plated Insulator pad around pins: Silicone rubber Case: Aluminum material with anodized finish Weight: 39.2 (1.4oz) Tolerance Inches Millimeters •XX ± 0.020 •X ± 0.5 •XXX ± 0.010 •XX ± 0.25 Pin: ± 0.002 ± 0.05 Thermal derating for vertical orientation, Vin=54V Output Voltage (Volts) 5.0 Output Current at 40°C (Amps) Output Current at 60°C (Amps) Output Current at 80°C (Amps) Free Air 200 LFM 300 LFM Free Air 200 LFM 300 LFM Free Air 200 LFM 300 LFM 5.0 5.0 5.0 4.6 5.0 5.0 0.3 1.8 3.8 The information and specifications contained in the specification are believed to be accurate and reliable at the time of publication. Specifications are subject to change without notice. Broadband TelCom Power, Inc. – 1719 S. Grand Avenue, Santa Ana, CA 92705 U.S.A. P 2 of 11 Tel.: 714-259-4888 • Fax: 714-259-0840 • www.btcpower.com • Email: [email protected] PS S25-48-5 Rev 3 16-1-04 BTCPower TM Technical Specification S25-48-5, S25-48-5N 48Vin 5Vout 5.0A Electrical Specifications Ta=25°C, Vin=48V unless otherwise noted. PARAMETER Absolute maximum rating Input voltage Operating case temperature Storage temperature Humidity Input characteristics Operating input voltage range Turn on voltage threshold Turn off voltage threshold Transient withstand Maximum input current Off converter input current Output characteristics Output voltage set point Output voltage line regulation Output voltage load regulation Output voltage trim range Output voltage ripple and noise Output over power protection Over-voltage protection Over-temperature protection Temperature coefficient Capacitive Load Output dynamic characteristics Startup time Transient recovery time Transient peak deviation Efficiency (see efficiency curve) 100% load efficiency Isolation characteristics Isolation voltage (primary to secondary ) Isolation voltage (primary to case) Isolation voltage (secondary to case) Isolation resistance Isolation capacitance Feature Characteristics Switching frequency ON/OFF control (Positive logic) Converter On Converter Off ON/OFF control (Negative logic) Converter On Converter Off Output voltage trim range Calculated MTBF Weight NOTES MIN TYP 0 -40 -55 36 48 35 MAX UNIT 80 100 125 95 V °C °C % 75 V V V V A mA 34 100 0.85 36 Transient duration: 100ms 100% load , 36Vin 48Vin 5 36~75 Vin 10%-100%Load 20Mz bandwidth, 100% Load, 48Vin 50 120 100 6.2 ±0.04 100,000 V % % % mV(pk-pk) % V °C %/°C µF 100 800 2 ms µs %Vo ±0.3 ±0.5 ±10 100 140 7.1 100 0 5% to 95% of the output voltage 25% load change 25% load change 50 48 Vin 88 % 1500 1000 1000 1000 VDC VDC VDC MΩ pF 275 KHz 1minute 1minute 1minute 500VDC, Primary to secondary Primary to secondary 10 225 250 S25-48-5 3 -1 7 1.2 V V S25-48-5N -1 3 -10 900,000 1.2 7 +10 V V % Hrs g(oz) Percentage of normal output Bellcore @ 50°C 28(1.0) Broadband TelCom Power, Inc. – 1719 S. Grand Avenue, Santa Ana, CA 92705 U.S.A. P 3 of 11 Tel.: 714-259-4888 • Fax: 714-259-0840 • www.btcpower.com • Email: [email protected] PS S25-48-5 Rev 3 16-1-04 BTCPower TM Technical Specification S25-48-5, S25-48-5N 48Vin 5Vout 5.0A Basic Operation And Functions S25-48-5/S25-48-5N is a high efficiency, isolated DC/DC converter. Neither heat sink nor airflow is required when the unit operates at ambient temperature of 25°C. The unit has basic control, output adjustment and protection functions. Input (Pin 2, Pin 3) Input power Vin(+) must be connected to Positive input pin 3; Input power Vin(-) must be connected to Negative input pin2. Output (Pin 4, Pin 6) Output power Vout(+) must be connected to Positive output pin 4; Output power Vout(-) must be connected to Negative output pin6. ON/OFF (Pin 1) Permits the user to maintain unit On/Off, in order to properly sequence different power supplies and reduce power consumption during the standby condition. There are two ON/OFF control options: positive logic (S25-48-5) and negative logic (S2548-5N). Both are referenced to Vin-. Remote Sense The unit does NOT have remote sense pins. Output Trim (Pin 6) Permits the user to adjust the output voltage up or down to achieve the custom voltage or to make the output voltage margining. The unit’s output voltage can be adjusted up10% or down 10% relative to the rated output voltage by adding an external resistor between pin 6 and one of the output pins (pin 4 and 5). To increase the output voltage, a trim resistor should be connected between pin 6(Trim) and pin 5 (Vout-), as shown in Fig 2. To decrease the output voltage, a trim resistor should be connected between pin 6 (Trim) and pin 4 (Vout+), as shown in Fig 3. The recommended trim resistor values can be found in the trim table (Table 1) and charts (Fig 4 and 5). Pin 1 is the "Enable" pin, connecting a TTL compatible pin. A TTL control signal to this pin, according to the specification, turns the unit on or off. The positive logic unit turns on when the pin is at logic high or open, and turns off at logic low. The negative logic unit turns on when the pin is at logic low, and turns off at logic high state. Typical ON/OFF connection is shown in Fig 1. Fig 2. Configuration for increasing the output voltage Fig 1. Recommended ON/OFF circuit configuration Fig 3. Configuration for decreasing the output voltage Broadband TelCom Power, Inc. – 1719 S. Grand Avenue, Santa Ana, CA 92705 U.S.A. P 4 of 11 Tel.: 714-259-4888 • Fax: 714-259-0840 • www.btcpower.com • Email: [email protected] PS S25-48-5 Rev 3 16-1-04 BTCPower TM Technical Specification S25-48-5, S25-48-5N 48Vin 5Vout 5.0A Trim resistace (k) 120 Protection Features 100 80 Input under voltage lockout (UVL) 60 The input voltage must be at least 35V for the unit to turn on. Once the unit has been turned on, it will shut off when the input voltage drops below 34V. 40 20 0 1 2 3 4 5 6 7 8 9 10 Trim-up Vout change (%) The unit is protected against over current or short circuit on the output. When sensing an over current condition, the unit will enter constant current operation and reduce the output voltage. Upon short-circuit condition, the unit will shut down. Fig 4 Trim-up output vs. trim resistance Trim resistace (k) 140 After over-current or short circuit condition is removed, the unit will resume normal operation automatically. 120 100 80 Output Over Voltage Protection (OVP) 60 40 20 0 1 2 3 4 5 6 7 8 9 10 Trim-down Vout change (%) Fig 5 Trim-down output vs. trim resistance Table 1 Output voltage trim vs. trim resistor value Trim Voltage +10% +9% +8% +7% +6% +5% +4% +3% +2% +1% Output Over-Current Protection (OCP) Trim Resistor 2.08k 3.38k 5.00k 7.10k 9.87k 14.22k 20.30k 31.20k 51.00k 109.70k Trim Voltage -10% -9% -8% -7% -6% -5% -4% -3% -2% -1% Trim Resistor 0.28k 1.77k 3.60k 5.97k 9.46k 14.17k 20.20k 32.96k 55.82k 127.6k This unit will shut down and latch off if the output voltage exceeds the over protection point. The over-voltage-protection latch is reset only by another cycle of the input power. The OVP set point is between 6.2V~7.1V. Over Temperature Protection (OTP) This unit will shut down if the case temperature exceeds the over temperature set point. The unit will resume normal operation automatically when the case temperature drops down. The OVP set point is around 100°C. Broadband TelCom Power, Inc. – 1719 S. Grand Avenue, Santa Ana, CA 92705 U.S.A. P 5 of 11 Tel.: 714-259-4888 • Fax: 714-259-0840 • www.btcpower.com • Email: [email protected] PS S25-48-5 Rev 3 16-1-04 BTCPower TM Technical Specification S25-48-5, S25-48-5N 48Vin 5Vout 5.0A Application Considerations Input source Impedance The unit has been designed to be stable with no external capacitor when used in a low inductance input and output circuit. • Never ground either of the input pins of the unit without grounding one of the output pins. This may allow a non-SELV voltage to appear between the output pin and ground. Electromagnetic Compatibility (EMC) However in many applications, the inductance with the distribution from the power source to the input of the unit can affect the stability of the unit. An external capacitor across the input will improve the stability of the unit. Also in many applications, the user has to use decoupling capacitors at the output load, to ensure the hold up time for the load. The unit’s conducted emission meets the requirement of EN55022 Class B Specifications, so no external input filter is needed unless a stricter conducted EMI/EMC limitation is required to satisfy or user has its own requirement on the input. Fig 6 shows the measured conducted EMC. Six-sided metal shields for zero radiate emission. Safety Requirements (SR) The unit meets UL/CSA/TUV safety requirements per UL60950, TUV EN60950 and CSA C22.2 No.60950-00. Basic insulation is provided between input and output. Caution: The unit does NOT have a fuse inside. The safety agencies require an external normal-blow fuse to be used at the input side to achieve maximum safety. The recommended fuse rating is 2A/100V. 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 unit output to be considered meeting the requirements of safety extra low voltage (SELV), all of the following must be met: • The input source is to be provided with reinforced insulation from any hazardous voltage, including the ac main. • The input pins of the unit are not operator accessible. • For the whole system, for safety agencies requirements, and for the combination of the unit input side (primary side) and the output side (secondary side), verify that under a single fault, hazardous voltages do not appear at the unit output side (secondary side). Fig 6. Conducted EMC (150KHz-30MHz) test result, the upper trace is the limit of EN55022 Class B specification Input Transient Withstand (ITW) The unit can withstand input transient voltage with 100V/100ms pulse and never be damaged. Broadband TelCom Power, Inc. – 1719 S. Grand Avenue, Santa Ana, CA 92705 U.S.A. P 6 of 11 Tel.: 714-259-4888 • Fax: 714-259-0840 • www.btcpower.com • Email: [email protected] PS S25-48-5 Rev 3 16-1-04 BTCPower TM Technical Specification S25-48-5, S25-48-5N 48Vin 5Vout 5.0A Characterization General information This unit has many operational characterized aspects including thermal derating, efficiency, start up and overshoot, output ripple & noise, dynamic response, over current protection curve and etc. Efficiency with nominal input (48V) at different ambient temperatures (25°C, 40°C and 55°C) is also given in Fig 12. Dynamic Response The following pages contain specific plots or waveforms associated with the unit. Additional comments for specific data are provided below. The dynamic response of the unit at load step is shown in Fig 13. The output load current change from 50% to 75% and return to 50% at the slew of 0.1A/µs. The input is 48V and a filter of 10µF tantalum capacitor plus a 1µF ceramic capacitor is put parallel to the output. Test Conditions Ripple and Noise All data presented were taken with the unit soldered to a test board, which is a 0.060” thick printed circuit board. No heat sink was used during all measurements. No airflow was used except in the de-rating test. The output voltage waveform has been measured at full load condition, with 10µF tantalum capacitor plus 1µF Ceramic capacitor closely parallel to the unit’s output. Fig 14 shows the output ripple and noise waveform. For the input line, a 1µF /100V ceramic capacitor has been used during all these tests. On the output side, a 10µF tantalum capacitor with Esr < 0.12Ω and 1µF ceramic capacitor has been used. The capacitors on both the input and output sides were close to the unit. NOTE: It is important to make sure that the components on the unit do not exceed their rating. Start up The startup scenarios are explained in Fig 7 and 8. The measured waveforms showing the turn on transient are given in Fig 9 and 10, for both positive and negative logic control units. Thermal De-rating For thermal de-rating test, the output current vs. the ambient temperature and the airflow rates has been measured, and the results are given in Fig 15. The ambient temperature varies between 50°C and 85°C with the airflow of 0, 100 and 200LFM (0, 0.5m/s and 1m/s). Others Other curve and waveforms presented include the output voltage vs. current curve (Fig 16) and the input current ripple waveform at full load condition (Fig 17) Efficiency Efficiency vs. load current curve at different inputs of 36V, 48V and 75V is given in Fig 11. The ambient temperature is 25°C. Broadband TelCom Power, Inc. – 1719 S. Grand Avenue, Santa Ana, CA 92705 U.S.A. P 7 of 11 Tel.: 714-259-4888 • Fax: 714-259-0840 • www.btcpower.com • Email: [email protected] PS S25-48-5 Rev 3 16-1-04 BTCPower TM Technical Specification S25-48-5, S25-48-5N 48Vin 5Vout 5.0A Start up Information Scenario #1: Initial Start up from power supply On/Off function enabled, the unit starts via input voltage Vin, see Fig 7. Time t0 Comments On/Off pin is On: system front-end power is switched on, Vin to unit begins to rise. t1 Vin crosses Under Voltage Lockout protection circuit threshold: the unit enabled to be on t2 The unit begins to turn on ( unit turn-on delay). t3 Unit output voltage reaches 100% of normal voltage. For this example, the unit total start up time (t3- t1) is typically 200us. Scenario #2: Initial Start up using On/Off Pin With Vin previously powered, the unit starts via On/Off pin, see Fig 8. Time t0 t1 t2 t3 Comments Vin at nominal value. Arbitrary time when On/Off pin is enabled (Unit enabled) End of unit turn-on delay Unit Vout reaches 100% of nominal voltage. Fig 7. Start up waveform For this example, the unit total start up time (t3- t1) is typically 300us. Fig 8. Start up using On/Off pin Broadband TelCom Power, Inc. – 1719 S. Grand Avenue, Santa Ana, CA 92705 U.S.A. P 8 of 11 Tel.: 714-259-4888 • Fax: 714-259-0840 • www.btcpower.com • Email: [email protected] PS S25-48-5 Rev 3 16-1-04 BTCPower TM Technical Specification S25-48-5, S25-48-5N 48Vin 5Vout 5.0A Turn-On Transient Waveforms Efficiency Curves Efficiency (%) 90 85 80 36V 75 48V 70 75V 65 1 2 3 4 5 Output current (A) Fig 9. Startup under positive logic control at Vin=48v, Iout =5A. Ch2: ON/OFF signal (1V/div) , Ch1: Output voltage (2V/div), Co=10µF tantalum capacitor + 1µF Ceramic capacitor, time scale: 200µs/div Fig 11. Efficiency vs. output current at various Input voltage The ambient temperature is 25°C. Efficiency (%) 90 85 80 25°C 75 40°C 70 55°C 65 1 2 3 4 5 Output current (A) Fig 10. Startup under negative logic control at Vin=48v, Iout =5A. Ch1: ON/OFF signal (5V/div) , Ch2: Output voltage (2V/div), Co=10µF tantalum capacitor + 1µF Ceramic capacitor, time scale: 200µs/div Fig 12. Efficiency at nominal input (48V) vs. load at different ambient temperatures of 25°C, 40°C, 55°C without air flow, the input voltage is 48V. Broadband TelCom Power, Inc. – 1719 S. Grand Avenue, Santa Ana, CA 92705 U.S.A. P 9 of 11 Tel.: 714-259-4888 • Fax: 714-259-0840 • www.btcpower.com • Email: [email protected] PS S25-48-5 Rev 3 16-1-04 BTCPower TM Technical Specification S25-48-5, S25-48-5N 48Vin 5Vout 5.0A Fig 14. Output voltage Ripple & Noise at Vin=48v, Iout=5A Co=10µF tantalum capacitor + 1µF Ceramic capacitor, ch1: 20mV/div, time scale: 2µs/div. Thermal De-Rating Curve Output current(A) Dynamic Response Waveform 6 5 4 3 0LFM 2 100FM 1 200LF M 0 50 55 60 65 70 75 80 85 Ambient Temperature(°C) Fig 15. Maximum output current vs. temperature. Both the input and output voltages are nominal . Fig 13. Dynamic response of load step at Vin=48v, Ch1: output voltage change(100mv/div), Ch2: output current step of 50%-75%-50% (2A/div). Current slew rate:0.1A/µs, Co=10µF tantalum capacitor + 1µF Ceramic capacitor, time scale: 1ms/div Output Ripples and Noise Waveform Over Current Protection Curve Fig 16. Output voltage vs current showing current limit point and converter shut down point Broadband TelCom Power, Inc. – 1719 S. Grand Avenue, Santa Ana, CA 92705 U.S.A. P 10 of 11 Tel.: 714-259-4888 • Fax: 714-259-0840 • www.btcpower.com • Email: [email protected] PS S25-48-5 Rev 3 16-1-04 BTCPower TM Technical Specification S25-48-5, S25-48-5N 48Vin 5Vout 5.0A Input Current Ripple Waveform Fig 17. Input current ripple with full output load at 48V input (50mA/div), time scale: 1µs/div Broadband TelCom Power, Inc. – 1719 S. Grand Avenue, Santa Ana, CA 92705 U.S.A. P 11 of 11 Tel.: 714-259-4888 • Fax: 714-259-0840 • www.btcpower.com • Email: [email protected] PS S25-48-5 Rev 3 16-1-04