ALH25AF48(N) Series Te c h n i c a l R e f e r e n c e N o t e s 48V Input, 5V&3.3V Dual Output 100W DC-DC Converter (Rev01) TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Asia 852-2437-9662 852-2402-4426 -1Publishing Date: 20020624 ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R Introduction Features ALH25AF48(N) half-brick dual output products 1. Two independent positive outputs provide two independent and fully regulated 2. Each output is separately trimmable positive outputs, the outputs are also separately trimmable. A remote on/off feature is includ- 3. Remote control function 4. High efficiency ed as standard. ALH25AF48(N) dual output iso5. High power density lated DC/DC converters are built using the industry standard half-brick pin-out and package 61.0mm x 57.9mm x 12.7mm (2.4" x 2.28" 6. Low output noise 7. Open frame structure x 0.5"). Typical efficiencies are 88% for the 8. Input undervoltage protection 5V/3.3V outputs. The ALH25AF48(N) dual out- 9. Short circuit protection put series are available with 2:1 input range of 10. Over current protection 36V-75V, and with output combination of 5V/3.3V at maximum current of 25 Amps and 11. Output overvoltage protection 12. Over-temperature protection output power is less than 100W. The maximum 13. current can be drawn from either output, or in any combination, as long as the total output Wide operating board temperature: -40C ~ 110C 14. No minimum load requirement current does not exceed 25 Amps and the output power is 100W. The input-output isolation is 1500Vdc. ALH25AF48(N) half-brick dual output products are designed to meet CISPR22, EN55022, UL, TUV, and CSA certifications. TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Asia 852-2437-9662 852-2402-4426 -2www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R Typical Application NOTE: CNT logic is optional. Positive Logic Control (for ALH25AF48): Low=Off, High=On. Negative Logic Control (for ALH25AF48N): Low=On, High=Off. Recommended External components: Fuse : Recommended: 10A. C1 : Recommended 100F/100V (use two parallel if Ta< -5C). C3=C5* : Recommended electrolytic capacitor of 1000F/10V(LOW ESR). C2=C4 : Recommended metallitic film capacitor of 1F/50V. Note*: For C3 and C5, the minimum output capacitor is 470F/10V. If Ta< -5C, the minimum external load capacitor is 440F( 2X220F tantalum capacitor parallel) Block Diagram +Vin -Vin 1 EMI Filter 4 +Vo1 5 -Vo1 6 TRM1 7 +Vo2 8 -Vo2 9 TRM2 OCP 2 To -Vin Feedback CNT 3 PWM PWM TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Error AMP Asia 852-2437-9662 852-2402-4426 -3www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R Model Numbering ALH 25 A F 48 N - 7 1 2 3 4 5 6 7 Note: 1--- Product series name 2--- Output rated current 3--- First rated output voltag is 5V 4--- Second rated output voltage is 3.3V 5--- Input rated voltage is 48V 6--- CNT Optional Mark: N presents negative logic, default is positive logic 7--- Pin length Default: 4.8mm 0.5mm ( 0.189in. 0.02in.) 7: 5.8mm 0.5mm ( 0.228in. 0.02in.) 6: 3.8mm 0.25mm ( 0.15in. 0.01in.) 8: 2.8mm 0.25mm ( 0.11in. 0.01in.) Ordering Information Model Number Input Voltage (V) Output Voltage (V) Output Current ( A )max Ripple & Noise (mV pp) max 48 5, 3.3 20, 25 100 ALH25AF48(N)-7 ALH25AF48(N)-6 ALH25AF48(N) 48 48 5, 3.3 5, 3.3 20, 25 20, 25 100 100 Efficiency* (%) min typ notes and conditions 86 88 Io1=20A, Io2=0A 85 87 Io1=10A, Io2=15A 80 82 Io1=0A, Io2=25A 86 88 Io1=20A, Io2=0A 85 87 Io1=10A, Io2=15A 80 82 Io1=0A, Io2=25A 86 88 Io1=20A, Io2=0A 85 87 Io1=10A, Io2=15A 80 82 Io1=0A, Io2=25A Note: *: Testing conditions are: Ta=25C, wind velocity=300ft./min. TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Asia 852-2437-9662 852-2402-4426 -4www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R Absolute Maximum Rating Characteristic Min Input Voltage(continuous) Typ Max Units -0.3 80 Vdc Input Voltage(peak/surge) -0.3 100 Vdc Board temperature -40 110 C storage temperature -55 125 C Notes 100ms non-repetitive Input Characteristics Characteristic Input Voltage Range Min Typ Max Units 36 48 75 Vdc 12 25 mAp-p Input Reflected Current Turn-off Input Voltage 30 33 35 V Turn-on Input Voltage 31 34.5 36 V Turn On Time 6 20 ms Turn On Delay 8 20 ms Typ Max Units Notes Vin=48V, Io1=10A, Io2=15A CNT Function Characteristic Min Notes Logic High 3 10 Vdc Logic Low -0.7 1.2 Vdc 2 mA Max Units Notes k Hrs 25C (board) Control Current Logic optional. General Specifications Characteristic MTBF Min Typ 1200 Isolation 1500 Vdc Pin solder temperature 260 C 5 s Hand Soldering Time Weight TEL: FAX: USA 1-760-930-4600 1-760-930-0698 80 Europe 44-(0)1384-842-211 44-(0)1384-843-355 wave solder < 15 s iron temperature 425C grams Asia 852-2437-9662 852-2402-4426 -5www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R ALH25AF48(N) Output Characteristic Characteristic Min Power Output Current Output Setpoint Voltage Typ Max Units 100 W 20/25 A Notes 4.95 5 5.05 Vdc Vin=48V, Io1=10A, Io2=15A 3.25 3.3 3.35 Vdc Vin=48V, Io1=10A,Io2=15A Vo1 0.2 %Vo Vin=36~75V, Io1=10A, Io2=15A Vo2 0.2 %Vo Vin=36~75V, Io1=10A, Io2=15A Vo1 0.5 %Vo Io1=0~20A, Io2=0A, Vin=48V Vo2 0.5 %Vo Io1=0A, Io2=0~25A, Vin=48V 2 3 %Vo DI/Dt=1A/10s 100 500 s DI/Dt=1A/10s 2 3 %Vo DI/Dt=1A/10s 100 500 s DI/Dt=1A/10s 37.5 A Io1+Io2 30 A(rms) Line Regulation Load Regulation Dynamic Response 50%-75%-50% load 25%-50%-25% load Current Limit Threshold 26 Short Circuit Current Efficiency 85 Trim Range 90 110 %Vo Over Voltage Protection Vo1 5.7 7 V Vo2 3.9 5 V -0.03 0.03 %Vo/C 100 mV 125 C Temperature Regulation 87 Ripple&Noise (mV pp) Over Temperature Protection Switching Frequency TEL: FAX: USA 1-760-930-4600 1-760-930-0698 111 250 Europe 44-(0)1384-842-211 44-(0)1384-843-355 % Vin=48V, Io1=10A, Io2=15A Both output ( 0-20MHz BW, Tboard=25C ) kHz Asia 852-2437-9662 852-2402-4426 -6www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R Characteristic Curves ALH25AF48N Typical Efficiency Vs Vin Io2 decrease by 10%, Io1 increase by 10% 100 92 90 90 Efficiency(%) Efficiency(%) ALH25AF48N Typical Efficiency Vs Vin Io2=1.5Io1 80 vin=75V 70 88 Vin=75V 86 Vin=48V vin=48V 60 84 vin=36V 50 82 1 2 3 4 5 6 7 8 9 10 Vin=36V 25 20 15 100 100 90 90 80 Vin=36V Vin=48V Vin=75V 80 Vin=36V 70 Vin=48V Vin=75V 60 50 50 2 6 10 14 18 1 USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 5 9 13 17 21 25 Io2(amps) Io1(amps) TEL: FAX: 0 ALH25AF48N Typical Efficiency vs Vin 5V:no load; 3.3V load variable Efficiency(%) Efficiency(%) ALH25AF48N Typical Efficiency vs Vin 5V: load variable; 3.3V no load 60 5 Io2(amps) Io1(Io2=1.5Io1) (amps) 70 10 Asia 852-2437-9662 852-2402-4426 -7www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R Characteristic Curves TEL: FAX: (continued ) ALH25AF48N Typical Transient Response 25%- 50%- 25%(Io2) Ch1:Vo1 Ch2:Vo2 ALH25AF48N Typical Transient Response 50%- 75%- 50%(Io2) Ch1:Vo1 Ch2:Vo2 ALH25AF48N Typical Transient Response 25%- 50%- 25%(Io1) Ch1:Vo1 Ch2:Vo2 ALH25AF48N Typical Transient Response 50%- 75%- 50%(Io1) Ch1:Vo1 Ch2:Vo2 USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Asia 852-2437-9662 852-2402-4426 -8www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R Characteristic Curves TEL: FAX: (continued ) ALH25AF48N Typical Output Voltage Startup From CNT On Ch1:Vo1 Ch2:Vo2 Ch3:CNT ALH25AF48N Typical Output Voltage Startup From CNT Off Ch1:Vo1 Ch2:Vo2 Ch3:CNT ALH25AF48N Typical Output Voltage Startup From Power Off Ch1:Vo1 Ch2:Vo2 Ch3:Vin ALH25AF48N Typical Output Voltage Startup From Power On (Ch1:Vo1 Ch2:Vo2 Ch3:Vin) USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Asia 852-2437-9662 852-2402-4426 -9www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R Characteristic Curves (continued ) ALH25AF48N Ripple&Noise Vin=75V Io1=10A Io2=15A Ch1:Vo1 Ch2:Vo2 TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Asia 852-2437-9662 852-2402-4426 -10www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R Pin Location The +Vin and -Vin input connection pins are located as shown in Figure 1. ALH25AF48(N) converters have a 2:1 input voltage range and 48 Vin converters can accept 36-75 Vdc. Care should be taken to avoid applying reverse polarity to the input which can damage the converter. Input Reverse Voltage Voltage Protection Under installation and cabling conditions where reverse polarity across the input may occur, reverse polarity protection is recommended. Protection can easily be provided as shown in Figure 2. In both cases the diode rating is 10A/100V. Placing the diode across the inputs rather than in-line with the input offers an advantage in that the diode only conducts in a reverse polarity condition, which increases circuit efficiency and thermal performance. Trim1 +Vin -Vo1 2.40 (60.96) CNT +Vin +Vin -Vin -Vin +Vo1 Trim2 -Vo2 -Vin +Vo2 2.28 (57.91) Fig.1 Pin Location (component-side view) Input Characteristic Fusing The ALH25AF48(N) power modules have no internal fuse. An external fuse must always be employed! To meet international safety requirements, a 250 Volt rated fuse should be used. Standard safety agency regulations require input fusing. Recommended fuse ratings for the ALH25AF48(N) series are 10A. TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Fig.2 Reverse Polarity Protection Circuits Europe 44-(0)1384-842-211 44-(0)1384-843-355 Input Undervoltage Protection The ALH25AF48(N) series are protected against undervoltage on the input. If the input voltage drops below the acceptable range, the converter will shut down. It will automatically restart when the undervoltage condition is removed. Input Filter Input filters are included in the converters to help achieve standard system emissions certifications. Some users however, may find that additional input filtering is necessary. The ALH25AF48(N) series have an internal switching frequency of 250 kHz, so a high frequency capacitor mounted close to the input terminals produces the best results. To reduce reflected noise, a capacitor can be added across the input as shown in Figure 3, forming a filter. A 100F/100V electrolytic capacitor is recommended for C1. Asia 852-2437-9662 852-2402-4426 -11www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R +Vin C1 -Vin Fig.3 Ripple Rejection Input Filter For conditions where EMI is a concern, a different input filter can be used. Figure 4 shows an input filter designed to reduce EMI effects. C1 is a 100F/100V electrolytic capacitor, and C2 is a 0.68F/100V metal film or ceramic high frequency capacitor. Cy1, Cy2, Cy3 and Cy4 are each 0.033F/630V high frequency ceramic capacitors. Cy5, Cy6, Cy7 and Cy8 are each 4700pF/1000V high frequency ceramic capacitors. L1 is a 1.8mH common mode choke. Co is the output capacitor, it can refer to the output capacitor of C3 and C5 in Typical Application on page 3. +Vin Cy1 +Vo1 CNT Function The ALH25AF48(N) series provide a control function allowing the user to turn the output on and off using an external circuit. ALH25AF48 series are the positive logic control and ALH25AF48N series are the negative logic control. For ALH25AF48 series applying a voltage less than 1.2V to the CNT pin will disable the output, and applying a voltage greater than 3V will enable it. For ALH25AF48N series applying a voltage less than 1.2V to the CNT pin will enable the output, and applying a voltage greater than 3V will disable it, If the remote on/off function is not used: Leave CNT pin open for positive logic. Connect CNT pin to ground for negative logic. The maximum voltage that can be applied to the CNT pin is 10V. CNT Cy5 + Co -Vin Cy3 C1 C2 -Vo1 +Vo2 L1 Cy2 Cy4 -Vin -Vo2 Fig.5 Simple Control Cy6 Cy7 + Co CNT Cy8 -Vin Fig.6 Transistor Control Fig.4 EMI Reduction Input Filter CNT When a filter inductor is connected in series with the power converter input, an input capacitor C1 should be added. An input capacitor C1 -Vin Fig.7 Isolated Control should also be used when the input wiring is long, since the wiring can act as an inductor. Failure to use an input capacitor under these conditions can produce large input voltage spikes and an unstable output. CNT -Vin Fig.8 Relay Control TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Asia 852-2437-9662 852-2402-4426 -12www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R Input-Output Characteristic Safety Consideration 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 EN60950. The input-to-output 1500VDC isolation is an operational insulation. The DC/DC power module should be installed in end-use equipment, in compliance with the requirements of the ultimate application, and is intended to be supplied by an isolated secondary circuit. When the supply to the DC/DC power module meets all the requirements for SELV(<60Vdc), the output is considered to remain within SELV limits (level 3). If connected to a 60Vdc power system, double or reinforced insulation must be provided in the power supply that isolates the input from any hazardous voltages, including the ac mains. One Vi pin and one Vo pin are to be grounded or both the input and output pins are to be kept floating. Single fault testing in the power supply must be performed in combination with the DC/DC power module to demonstrate that the output meets the requirement for SELV. The input pins of the module are not operator accessible. 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. TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Output Characteristic Minimum Load Requirement There is no minimum load requirement for ALH25AF48(N) series. Output Over-Voltage Over-Voltage Protection The over-voltage protection has a separate feedback loop which activates when the output voltage Vo1 is between 5.7~7V, and Vo2 is between 3.9~5V. Output Trimming Trimming Users can increase or decrease the output voltage by adding an external resistor between the TRIM pin and either the Vo (+ ) or Vo ( - ) pins. The trim resistor should be positioned close to the module. If the trim feature is not used, leave the TRIM pin open. Trimming up by more than 10% of the nominal output may damage the converter. Trimming down more than 10% can cause the converter to regulate improperly. Trim down and trim up circuits and equations are shown in following Figures (on the next two page). Note that at elevated output voltages the maximum power rating of the module remains the same, and the output current capability will decrease correspondingly. Asia 852-2437-9662 852-2402-4426 -13www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R pin-side view Vo2+ Vo2+ -Vin -Vin Vo2- Vo2- Trim2 Trim2 Vo1+ Load Vo1- Ru1 = CNT Vo1- Ru1 Trim1 +Vin 16 - 2.7Vo Vo - 5 ( 5.825 - Vo ) x 0.33 Vo - 3.3 Where Vo is the output voltage after trim-down. Ru2 is in k. Fig.9 Output Voltage Vo1 Trim-up Fig.11 Output Voltage Vo2 Trim-up 5.5 3.63 5.45 Output Voltage Trim-up ( volts ) Output Voltage Trim-up ( volts ) Trim1 3.3V Out: Ru2= Where Vo is the output voltage after trim-up. Ru1 is in k. 5.4 5.35 5.3 5.25 5.2 5.15 5.1 5.05 5 3.597 3.564 3.531 3.498 3.465 3.432 3.399 3.366 3.333 0 10 20 30 40 50 0 Adjustment Resistor Value (k) Fig.10 Typical Trim-up Curves for ALH25AF48(N) Series 5V Output TEL: FAX: Ru2 Vo1+ CNT +Vin Load USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 3 6 9 12 15 18 21 24 27 Adjustment Resistor Value (k) Fig.12 Typical Trim-up Curves for ALH25AF48(N) Series 3.3V Output Asia 852-2437-9662 852-2402-4426 -14www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R pin-side view Vo2+ Vo2+ -Vin -Vin Vo2- Vo2- Trim2 Trim2 Vo1+ Vo1+ CNT Rd1 = CNT Rd1 Vo1+Vin Vo1- Load +Vin Trim1 3.7Vo - 16 5 -Vo Rd2 Where Vo is the output voltage after trim-down. Rd1 is in k. Output Voltage Trim-down ( volts ) Output Voltage Trim-down ( volts ) 4.95 4.9 4.85 4.8 4.75 4.7 4.65 4.6 4.55 4.5 20 30 40 50 3.3 3.267 3.234 3.201 3.168 3.135 3.102 3.069 3.036 3.003 2.97 0 Adjustment Resistor Value (k) Fig.14 Typical Trim-down Curves for ALH25AF48(N) Series 5V Output TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 ( Vo - 2.89 ) x 0.66 3.3 - Vo Fig.15 Output Voltage Vo2 Trim-down 5 10 = Trim1 Where Vo is the output voltage after trim-down. Rd2 is in k. Fig.13 Output Voltage Vo1 Trim-down 0 Rd2 Load 1 2 3 4 5 6 7 8 Adjustment Resistor Value (k) Fig.16 Typical Trim-down Curves for ALH25AF48(N) Series 3.3V Output Asia 852-2437-9662 852-2402-4426 -15www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R Output Over-Current Protection ALH25AF48(N) series half-brick dual output products feature continuously current limiting as part of their Overcurrent Protection (OCP) circuits. When Io1+Io2 exceeds 26A, such as during a short circuit condition, the module will be in hiccup protection. Output Filters When the load is sensitive to ripple and noise, an output filter can be added to minimize the effects. A simple output filter to reduce output ripple and noise can be made by connecting a capacitor across the output as shown in Figure 17. The recommended value for the output capacitor C1 is 1000F/10V(LOW ESR). +Vout C1 Load -Vout Decoupling Noise on the power distribution system is not always created by the converter. High speed analog or digital loads with dynamic power demands can cause noise to cross the power inductor back onto the input lines. Noise can be reduced by decoupling the load. In most cases, connecting a 10 F tantalum capacitor in parallel with a 0.1F ceramic capacitor across the load will decouple it. The capacitors should be connected as close to the load as possible. Ground Loops Ground loops occur when different circuits are given multiple paths to common or earth ground, as shown in Figure 19. Multiple ground points can slightly different potential and cause current flow through the circuit from one point to another. This can result in additional noise in all the circuits. To eliminate the problem, circuits should be designed with a single ground connection as shown in Figure 20. Fig.17 Output Ripple Filter RLine RLine +Vout Load Extra care should be taken when long leads or traces are used to provide power to the load. Long lead lengths increase the chance for noise to appear on the lines. Under these conditions C2 can be added across the load as shown in Figure 18. The recommended component for C2 is 1000F/10V(LOW ESR) capacitor and connecting a 0.1F ceramic capacitor C1 in parallel generally. Load RLine -Vout RLine RLine Ground Loop RLine Fig.19 Ground Loops RLine RLine +Vout Load Load RLine -Vout RLine RLine Fig.20 Single Point Ground +Vout C1 C2 Load -Vout Fig.18 Output Ripple Filter For a Distant Load TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Parallel Power Distribution Figure 21. shows a typical parallel power distribution design. Such designs, sometimes called daisy chains, can be used for very low output currents, but are not normally recommended. The voltage across loads far from the source Asia 852-2437-9662 852-2402-4426 -16www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R can vary greatly depending on the IR drops along the leads and changes in the loads closer to the source. Dynamic load conditions increase the potential problems. I1 + I2 + I3 I2 + I3 I3 RL2 RL1 RL3 +Vout Load 1 Load 2 Load 3 -Vout RG2 RG1 RG3 RL = Lead Resistance RG = Ground Lead Resistance Fig.21 Parallel Power Distribution Radial Power Distribution Radial power distribution is the preferred method of providing power to the load. Figure 22 shows how individual loads are connected directly to the power source. This arrangement requires additional power leads, but it avoids the voltage variation problems associated with the parallel power distribution technique. +Vout RL3 RL1 RL2 Load 1 Load 2 Load 3 RG2 RG1 RG3 -Vout RL = Lead Resistance RG = Ground Lead Resistance Fig.22 Radial Power Distribution Mixed Distribution In the real world a combination of parallel and radial power distribution is often used. Dynamic and high current loads are connected using a radial design, while static and low current loads can be connected in parallel. This combined approach minimizes the drawbacks of a parallel design when a purely radial design is not feasible. Thermal Management Technologies The ALH25AF48(N) series feature high efficiency, the 5V/3.3 V output units have typical efficiency of 87% at full load. With less heat dissipation and temperature-resistant components such as ceramic capacitors, these modules exhibit good behavior during prolonged exposure to high temperatures. Maintaining the operating board temperature (Tc) within the specified range help keep internal-component temperatures within their specifications which in turn help keep MTBF from falling below the specified rating. Proper cooling of the power modules is also necessary for reliable and consistent operation. Basic Thermal Management Measuring the board temperature of the module (Tc) as the method shown in Figure 24 can verify the proper cooling. Figure 24 shows the board surface of the module and the pin locations. The module should work under 90C for the reliability of operation and TC must not exceed 110 C while operating in the final system configuration. The measurement can be made with a surface probe after the module has 11.5 (0.45) MEASURE CASE TEMPERATURE HERE Trim1 +Vin -Vo1 39.2 (1.54) CNT +Vo1 (Between MOSFET and thermal resistance) Trim2 +Vout -Vo2 RL3 RL1 Load 1 RG1 RL4 -Vin RL2 Load 2 Load 3 RG3 -Vout RG4 Dimensions: millimeters (inches) RL = Lead Resistance RG = Ground Lead Resistance Fig.23 Mixed Power Distribution TEL: FAX: USA 1-760-930-4600 1-760-930-0698 +Vo2 Load 4 RG2 Europe 44-(0)1384-842-211 44-(0)1384-843-355 component-side view Fig.24 Board Temperature Measurement Asia 852-2437-9662 852-2402-4426 -17www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R The module power dissipation then can be calculated through the equation. Because each power module output voltage has a different power dissipation curve, a plot of power dissipation versus output current over three different line voltages is given in each module-specific data sheet. The typical power dissipation curves of ALH25AF48N series are shown as figure 25 to figure 28. Power Dissipation(W) 14 12 10 Vin=36V 8 Vin=48V 6 Vin=75V 4 1 2 3 4 5 6 7 8 9 10 Io1(Io2=1.5Io1)(amps) Fig.25 ALH25AF48N Power Dissipation Curves, Io2=1.5Io1 18 Power Dissipation(W) tion below: PD = PI - PO where : PI is input power; PO is output power; PD is dissipated power. Also, module efficiency () is defined as the following equation: = PO / PI If eliminating the input power term, from two above equations can yield the equation below: PD = PO ( 1 - ) / 16 17 Vin=36V 16 Vin=48V 15 Vin=75V 14 13 12 11 10 25 20 22.5 15 17.5 10 12.5 5 7.5 0 2.5 Io2(amps) Fig.26 ALH25AF48N Power Dissipation Curves, 5V:10%increase, 3.3V:10%decrease 16 14 Power Disspation reached thermal equilibrium. It makes the assumption that the final system configuration exists and can be used for a test environment. The following text and graphs show guidelines to predict the thermal performance of the module for typical configurations that in natural or forced airflow environments. Note that Tc of module must always be checked in the final system configuration to verify proper operational due to the variation in test conditions. Thermal management acts to transfer the heat dissipated by the module to the surrounding environment. The amount of power dissipated by the module as heat (PD) is got by the equa- 12 10 Vin=36V 8 Vin=48V 6 Vin=75V 4 2 6 4 10 8 14 12 18 16 20 Io1(amps) Fig.27 ALH25AF48N Power Dissipation Curves, 5V:load variable, 3.3V:no load TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Asia 852-2437-9662 852-2402-4426 -18www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R 25 ALH25AF48N derating curves (Pd-Ta) ALH25AF48N DERATING CURVES (Pd-Ta) 20 0.1m/s 0.5m/s 1m/s 2m/s 15 Vin=36V 10 Vin=48V 5 Vin=75V 0 2 6 10 4 8 14 12 18 16 22 20 Power Dissipation(W) Power Disspation 20 15 10 5 25 0 24 0 Io2(amps) 20 40 60 80 100 120 Ambient Air Temperature(oC) The condition can be determined from the efficiency curves. Fig.28 ALH25AF48N Power Dissipation Curves, 5V:no load, 3.3V:load variable ALH25AF48N derating CURVES curves (Po-Ta) ALH25AF48N DERATING (Po -Ta) Module Derating 100 Output Power(W) 80 Experiment Setup From the experimental set up shown in figure 29, the derating curves as figure 30 can be drawn. Note that the PWB ( printed-wiring board ) and the module must be mounted vertically. The passage has a rectangular crosssection. The clearance between the facing PWB and the top of the module is kept 13 mm (0.5 in.) constantly. 60 40 0.1m/s 0.5m/s 1m/s 2m/s 20 0 0 20 40 60 80 100 120 Ambient Air Temperature(oC) Testing condition: Io2=1.5Io1 Fig.30 Forced Convection Power Derating 13(0.5) PWB facing PWB Air velocity and Ambient Temperature Testing Point Module 50.8(2.0) Air flow Dimensions: millimeters (inches). Convection Without Without Heat Sinks Heat transfer can be enhanced by increasing the airflow over the module. Figure 30 shows the maximum power that can be dissipated by the module. In the test, natural convection airflow was measured at 0.1 m/s (20 ft./min.). The 0.5 m/s to 2.0 m/s (100 ft./min. to 400 ft./min.) curves are tested with externally adjustable fans. The appropriate airflow for a given operating condition can be determined through figure 30. Fig.29 Experiment Set Up TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Asia 852-2437-9662 852-2402-4426 -19www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R Mechanical Considerations Installation Although ALH25AF48(N) series converters can be mounted in any orientation, free air-flowing must be taken. Normally power components are always put at the end of the airflow path or have the separate airflow paths. This can keep other system equipment cooler and increase component life spans. Soldering ALH25AF48(N) converters are compatible with standard wave soldering techniques. When wave soldering, the converters pins should be preheated for 20-30 seconds at 110 C, and wave soldered at 260C for less than 15 seconds. When hand soldering, the iron temperature should be maintained at 450C and applied to the converter pins for less than 5 seconds. Longer exposure can cause internal damage to the converter. Cleaning can be performed with cleaning solvent IPA or with water. MTBF The MTBF, calculated in accordance with Bellcore TR-NWT-000332 is 1,200,000 hours. Obtaining this MTBF in practice is entirely possible. ASTEC can supply replacements for converters from other manufacturers, or offer custom solutions. Please contact the Company for details. TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Asia 852-2437-9662 852-2402-4426 -20www.astec.com ALH25AF48(N) HALF-BRICK DUAL OUTPUT SERIES 3 6 V D C T O 7 5 V D C I N P U T, 1 0 0 W D C / D C C O N V E R T E R Mechanical Chart (pin-side view) 4- 1.5 (0.06) only +Vo and -Vo pins 10.2 (0.4) 61.0 (2.4) +Vo2 -Vin 7.62 (0.3) -Vo2 7.62 (0.3) Trim2 25.4 (1.0) 10.16 (0.4) +Vo1 CNT 7.62 (0.3) 10.16 (0.4) -Vo1 7.62 (0.3) +Vin 12.70 (0.5) 4.8 (0.19) 5- 1.0 (0.04) except Vo pins Trim1 48.26 (1.9) 57.9 (2.28) mm (inches) Tolerances: Inches .xx !0.020 .xxx !0.010 Pins >4mm <4mm Millimeters .x !0.5 .xx !0.25 !0.02inch ( !0.5mm) !0.01inch ( !0.25mm) 12.7 (0.5) 5.8(0.23)* Note*: Pin length is optional. Detailed information can refer to the Model Numbering on page 4. TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Asia 852-2437-9662 852-2402-4426 -21www.astec.com PART NUMBER DESCRIPTION ss pp c - 0 iv L - iv = Input Voltage 05 = Range centered on 5V 12 = Range centered on 12V 24 = 18 to 36(2:1), 9 to 36V(4:1) 36 = 20 to 60V 46 = 18V to 75V (4:1) 48 = Typ 36 to 75V xxx f - yy h n p - mx-Options p = Pin Length Omit this digit for Standard 5mm 6 = 3.8mm, 7= 5.8mm 8 = 2.8mm Enable Logic Polarity Omit for Positive Enable Logic N = Negative Enable Except: AK60C-20H, BK60C-30H Omit for Negative Logice P = Positive Logic c = Pinout compatability A= Astec Footprint or "non Lucent" footprint C= Ind Std, Exact Lucent drop in pp = Package Type 40 = 1" x 2" SMD 42 = 1.5" x 2" SMD 45 = 1.45" X 2.3" (1/4 Brk) 60 = 2.4" X 2.3" (1/2 Brk) 80 = Full size 4.6" x 2.4" 72= 2.35" X 3.3 (3/4 Brk) H = High Efficiency (Synch rect.) Omit H if Conventional Diode (low Eff) yy = Output Current ie. 08 = 8 Amps f = # of Outputs F = Single Output D = Dual Output xxx = Output Voltage Format is XX.X (ie 1.8V = 018) ss = Series AA = 1/2brick Dual (Old designator) mx = Options M1,M2 = .25" Height Heatsink M3,M4 = .5" height Heatsink M5.M6 = 1.0" Height Heatsink AK = Ind Std sizes (1/4, 1/2, full) <150W AM/BM = Full size, astec pin out AL = Half size, astec pin-out BK = Ind Std size =>150W or feature rich AV = Avansys Product Note: For some products, they may not conform with the PART NUMBER DESCRIPTION above absolutely. REVISION Q ATTACHMENT I Page 1 of 2 NEW PART NUMBER DESCRIPTION A c s ii V1 V2 V3 Output Voltage A = 5.0V F = 3.3V G = 2.5V D = 2.0V / 2.1V Y = 1.8V M = 1.5V K = 1.2V J = 0.9V Vin - e t p Mx E = 7.5V B = 12V, C = 15V L = 8V, H = 24V, R = 28V Omit V2 and V3 if Single Output Omit V3 if Dual Output ie for Dual Output 5 and 3.3V V1 =A, V2 = F, V3 =Omit V1 =A, V2 = F, V3 =Omit ii = Output Current Max ie 60 = 60 Amps Vin = Input Voltage range 300 = 250V to 450V 48 = 36V to 75V 24 = 18V to 36V 03 = 1.8V to 5.0V 08 = 5.0V to 13.0V PFC: Power Factor Corrected S = Size F = Full Brick H = Half Brick Q = Quarter Brick S = 1 X 2 18 Pin SMT E = 1 X 2 Thru Hole C = (.53X1.3X.33) SMT (Austin Lite drop in) V = Conventional Package (2X2.56") or ( A = SIP W = Convent pkg (Wide 2.5X3) R = 1 X 1 Thru Hole A = SIP T = 1.6 X 2 E = Enable Logic for > 15W Omit this digit for Positive enable N = Negative Logic E = Enable Logic for < 15W Omit this digit for no enable option 1 = Negative Logic 4 = Positive Logic c = Construction E = Enhanced Thermals (Baseplate or adapter plate) I = Integrated (Full Featured) Hong Kong models L = Low Profile (Open Frame, No case - Isolated) P = Open Frame (SIP or SMT) non-isolated Trim for 1W to 15W 9 = Trim Added P = Pin Length Omit this digit for Standard 5mm 6 = 3.8mm 8 = 2.8mm 7 = 5.8 mm Mx - Factory Options customer Specific Note: For some products, they may not conform with the NEW PART NUMBER DESCRIPTION above absolutely. REVISION Q ATTACHMENT I Page 2 of 2