AEH Half-brick 24V Input Series Te c h n i c a l R e f e r e n c e N o t e s 24V Input, 2.5V, 3.3V, 5V Output 50-150 Watt DC-DC Converter -1TEL: 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 www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Introduction Design Features The AEH 24Vin series comes in a industry stan- ! High Efficiency dard half-brick package of 2.4" x 2.28" x 0.5" ! High power density ! Low output noise ! Metal baseplate series is available with 2:1 input range of 18- ! CNT function 36V. Outputs of 2.5V, 3.3V, and 5V are fully iso- ! Remote sense lated from input and the isolation voltage is ! Trim function ! Input under-voltage lockout ! Output short circuit protection Designed using a synchronous rectification ! Output current limiting topology, AEH 24Vin series incorporates simple ! Output over-voltage protection structure, good electrical performance and high ! Overtemperature protection ! High input-output isolation voltage and footprint, and incorporates the super high efficiency up to 87% in 2.5V output and high power density up to 54.8W/in3. The AEH 24Vin 1500Vdc. The typical efficiencies are 88% for the 5V output, 87% for the 3V output, and 86% for the 2.5V output. reliability. Standard features include input LVP, OCP, output OVP, short circuit protection, and over-temperature protection. Using aluminum based plate, the maximum case temperature Options can reach 100 C without derating. The AEH 24Vin series is designed to meet CISPR22, FCC Class A, 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 ! Heat sink available for extended operation ! Choice of remote on/off logic configuration Asia 852-2437-9662 852-2402-4426 -2www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Typical Application Fuse* +Vin +Sense +Vo CNT Vin Trim CASE C1* C3 C4 C2* Load -Vo -Vin -Sense Fuse*: Use external fuse ( fast blow type ) for each unit. 50W output : 10A fuse 75W output : 15A fuse 100W output : 20A fuse 150W output : 40A fuse C1*: Recommended input capacitor C1 -20 oC ~ +100 oC : m 100uF/63V electrolytic or ceramic type capacitor. -40 oC ~ +100 oC : m 100uF/63V ceramic type capacitor only. C2*: Recommended output capacitor C2 -20 oC ~ +100 oC : 2200uF/10V (electrolytic capacitor) -40 oC ~ +100 oC : For this temperature range, use two pieces of the recommended capacitor above. C3: Recommended 4700pF/2000V C4: Recommended 1F/10V 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 -3www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Block Diagram Ordering Information Model Number Input Voltage Output Voltage Output Current Ripple (mV rms) Noise (mV pp) AEH10G24 AEH10F24 AEH10A24 *AEH15G24 *AEH15F24 *AEH15A24 AEH20G24 AEH20F24 AEH20A24 *AEH30G24 *AEH30F24 *AEH30A24 18-36V 18-36V 18-36V 18-36V 18-36V 18-36V 18-36V 18-36V 18-36V 18-36V 18-36V 18-36V 2.5V 3.3V 5V 2.5V 3.3V 5V 2.5V 3.3V 5V 2.5V 3.3V 5V 10A 10A 10A 15A 15A 15A 20A 20A 20A 30A 30A 30A 40 40 40 40 40 40 40 40 40 40 40 40 150 150 150 150 150 150 150 150 150 150 150 150 Efficiency min typ 84% 85% 86% 84% 85% 86% 84% 85% 86% 84% 84% 86% 86% 87% 88% 86% 87% 88% 86% 87% 88% 86% 86% 88% *: detailed information refering to the factory 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 AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Absolute Maximum Rating Characteristic Min Typ Max Units Input Voltage(continuous) -0.3 40 Vdc Input Voltage(peak/surge) -0.3 50 Vdc Case temperature -40 100 C storage temperature -55 125 C Notes 100ms non-repetitive Input Characteristics Characteristic Min Typ Max Units Input Voltage Range 18 24 36 Vdc 25 80 mAp-p Input Reflected Current Turn-off Input Voltage 14 15.5 17 V Turn-on Input Voltage 15 16.5 18 V 15 25 ms Typ Max Units 15 Vdc 1.2 Vdc 2 mA Turn On Time Notes Control Function Characteristic Logic High Min 3 Logic Low Control Current Notes Reverse logic option "P" available General Specifications Characteristic MTBF Min Typ 1,880 Units Notes k Hrs Bellcore TR332, Tc=30C Isolation 1500 Vdc Pin solder temperature 260 C wave solder < 10 s 5 s iron temperature 425C Hand Soldering Time Weight TEL: FAX: Max USA 1-760-930-4600 1-760-930-0698 70 Europe 44-(0)1384-842-211 44-(0)1384-843-355 grams Asia 852-2437-9662 852-2402-4426 -5www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t AEH10G24 Output Characteristics Characteristic Min Typ Max Units Power 25 W Output Current 10 A Output Setpoint Voltage 2.45 Notes 2.5 2.55 Vdc Vin=24V, Io=10A Line Regulation 0.02 0.2 %Vo Vin=18~36V, Io=10A Load Regulation 0.1 0.5 %Vo Io=0~10A, Vin=24V Dynamic Response 50-75% load 1 %Vo Ta=25C, DI/Dt=1A/10s 100 s Ta=25C, DI/Dt=1A/10s 1 %Vo Ta=25C, DI/Dt=1A/10s 100 s Ta=25C, DI/Dt=1A/10s 50-25% load Current Limit Threshold 11 12.5 Short Circuit Current A 17 A 86 % Efficiency 84 Trim Range 90 110 %Vo 3 3.9 V Sense Compensation 0.5 V Temperature Regulation 0.02 %Vo/C Over Voltage Protection Setpoint TEL: FAX: 14 Vin=24V, Io=10A 0.25V each leg Ripple (rms) 20 mV ( 0 to 20MHz Bandwidth ) Noise (p-p) 100 mV ( 0 to 20MHz Bandwidth ) Over Temperature Protection 105 C Switching Frequency 180 kHz 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 -6www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t AEH10F24 Output Characteristics Characteristic Min Typ Max Units Power 33 W Output Current 10 A Output Setpoint Voltage 3.25 Notes 3.3 3.35 Vdc Vin=24V, Io=10A Line Regulation 0.02 0.2 %Vo Vin=18~36V, Io=10A Load Regulation 0.1 0.5 %Vo Io=0~10A, Vin=24V 1 %Vo Ta=25C, DI/Dt=1A/10s 100 s Ta=25C, DI/Dt=1A/10s 1 %Vo Ta=25C, DI/Dt=1A/10s 100 s Ta=25C, DI/Dt=1A/10s Dynamic Response 50-75% load 50-25% load Current Limit Threshold 11 12.5 Short Circuit Current TEL: FAX: 14 A 17 A 87 % Efficiency 85 Vin=24V, Io=10A Trim Range 90 110 %Vo Over Voltage Protection Setpoint 3.9 5.0 V Sense Compensation 0.5 V Temperature Regulation 0.02 %Vo/C 0.25V each leg Ripple (rms) 20 mV ( 0 to 20MHz Bandwidth ) Noise (p-p) 100 mV ( 0 to 20MHz Bandwidth ) Over Temperature Protection 105 C Switching Frequency 270 kHz 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 -7www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t AEH10A24 Output Characteristics Characteristic Min Typ Max Units Power 50 W Output Current 10 A Output Setpoint Voltage 4.92 Notes 5.0 5.08 Vdc Vin=24V, Io=10A Line Regulation 0.02 0.2 %Vo Vin=18~36V, Io=10A Load Regulation 0.1 0.5 %Vo Io=0~10A, Vin=24V 1 %Vo Ta=25C, DI/Dt=1A/10s 100 s Ta=25C, DI/Dt=1A/10s 1 %Vo Ta=25C, DI/Dt=1A/10s 100 s Ta=25C, DI/Dt=1A/10s Dynamic Response 50-75% load 50-25% load Current Limit Threshold 11 12 Short Circuit Current A 17 A 87 % Efficiency 86 Trim Range 90 110 %Vo 5.75 7 V Sense Compensation 0.5 V Temperature Regulation 0.02 %Vo/C Over Voltage Protection Setpoint Ripple (rms) TEL: FAX: 14 Vin=24V, Io=10A 0.25V each leg 20 mV ( 0 to 20MHz Bandwidth ) Noise (pp) 100 mV ( 0 to 20MHz Bandwidth ) Over Temperature Protection 105 C Switching Frequency 330 kHz 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 AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t AEH20G24 Output Characteristics Characteristic Min Typ Max Units Power 50 W Output Current 20 A Output Setpoint Voltage 2.45 Notes 2.5 2.55 Vdc Vin=24V, Io=20A Line Regulation 0.02 0.2 %Vo Vin=18~36V, Io=20A Load Regulation 0.1 0.5 %Vo Io=0~20A, Vin=24V 1.5 %Vo Ta=25C, DI/Dt=1A/10s 100 s Ta=25C, DI/Dt=1A/10s 1.5 %Vo Ta=25C, DI/Dt=1A/10s 100 s Ta=25C, DI/Dt=1A/10s Dynamic Response 50-75% load 50-25% load Current Limit Threshold 22 25 Short Circuit Current A 30 A 86 % Efficiency 84 Trim Range 90 110 %Vo 3 3.9 V Sense Compensation 0.5 V Temperature Regulation 0.02 %Vo/C Over Voltage Protection Setpoint Ripple (rms) TEL: FAX: 28 Vin=24V, Io=20A 0.25V each leg 20 mV ( 0 to 20MHz Bandwidth ) Noise (pp) 100 mV ( 0 to 20MHz Bandwidth ) Over Temperature Protection 105 C Switching Frequency 180 kHz 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 AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t AEH20F24 Output Characteristics Characteristic Min Typ Max Units Power 66 W Output Current 20 A Output Setpoint Voltage 3.25 Notes 3.3 3.35 Vdc Vin=24V, Io=20A Line Regulation 0.02 0.2 %Vo Vin=18~36V, Io=20A Load Regulation 0.1 0.5 %Vo Io=0~20A, Vin=24V 1.5 %Vo Ta=25C, DI/Dt=1A/10s 100 s Ta=25C, DI/Dt=1A/10s 1.5 %Vo Ta=25C, DI/Dt=1A/10s 100 s Ta=25C, DI/Dt=1A/10s Dynamic Response 50-75% load 50-25% load Current Limit Threshold 22 25 Short Circuit Current A 30 A 87 % Efficiency 86 Trim Range 90 110 %Vo Over Voltage Protection Setpoint 3.9 5.0 V Sense Compensation 0.5 V Temperature Regulation 0.02 %Vo/C Ripple (rms) TEL: FAX: 28 Vin=24V, Io=20A 0.25V each leg 20 mV ( 0 to 20MHz Bandwidth ) Noise (pp) 100 mV ( 0 to 20MHz Bandwidth ) Over Temperature Protection 105 C Switching Frequency 330 kHz 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 AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t AEH20A24 Output Characteristics Characteristic Min Typ Max Units Power 100 W Output Current 20 A Output Setpoint Voltage 4.92 Notes 5.0 5.08 Vdc Vin=24V, Io=20A Line Regulation 0.02 0.2 %Vo Vin=18~36V, Io=20A Load Regulation 0.1 0.5 %Vo Io=0~20A, Vin=24V 1.5 %Vo Ta=25C, DI/Dt=1A/10s 100 s Ta=25C, DI/Dt=1A/10s 1.5 %Vo Ta=25C, DI/Dt=1A/10s 100 s Ta=25C, DI/Dt=1A/10s Dynamic Response 50-75% load 50-25% load Current Limit Threshold 22 24.5 Short Circuit Current A 30 A 88 % Efficiency 86 Trim Range 90 110 %Vo Over Voltage Protection Setpoint 5.75 7.0 V Sense Compensation 0.5 V Temperature Regulation 0.02 %Vo/C Ripple (rms) TEL: FAX: 28 Vin=24V, Io=20A 0.25V each leg 20 mV ( 0 to 20MHz Bandwidth ) Noise (pp) 100 mV ( 0 to 20MHz Bandwidth ) Over Temperature Protection 105 C Switching Frequency 330 kHz 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 -11www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Characteristic Curves (at 25 C ) Typical Efficiency AEH10F24 90 90 85 85 Efficiency (%) Efficiency (%) Typical Efficiency AEH10G24 80 75 70 Vin=18V 65 75 70 Vin=18V Vin=24V 65 Vin=24V Vin=36V 60 0 2 4 6 8 Vin=36V 60 10 0 2 4 6 8 Io Typical Efficiency AEH10A24 Typical Efficiency AEH20G24 90 90 85 85 80 80 75 70 75 70 Vin=18V 65 Vin=18V 65 Vin=24V Vin=24V Vin=36V 60 Vin=36V 60 0 2 4 6 8 10 0 4 8 Io 16 90 90 85 85 80 75 70 80 75 70 Vin=18V 65 Vin=18V 65 Vin=24V Vin=36V 60 4 8 12 16 20 60 0 Io TEL: FAX: USA 1-760-930-4600 1-760-930-0698 20 Typical Efficiency AEH20A24 Efficiency (%) Efficiency (%) 12 Io Typical Efficiency AEH20F24 0 10 Io Efficiency (%) Efficiency (%) 80 Vin=24V Vin=36V 4 8 12 16 20 Io Europe 44-(0)1384-842-211 44-(0)1384-843-355 Asia 852-2437-9662 852-2402-4426 -12www.astec.com AV E H i g h E f f i c i e n c y S e r i e s H a l f - B r i c k P o w e r C o n v e r t e r s 1 8 V D C t o 3 6 V D C I n p u t , 5 0 - 1 5 0 Wa t t Characteristic Curves Typical Output Overcurrent Characteristics AEH10F24 3 4 2.4 3.2 Output Voltage (volts) Output Voltage (volts) Typical Output Overcurrent Characteristics AEH10G24 (at 25 C ) 1.8 Vin=18V 1.2 Vin=24V Vin=36V 0.6 0 2.4 Vin=18V 1.6 Vin=24V Vin=36V 0.8 0 0 3 6 9 12 15 0 3 Output Curent (amps) 15 3 5 Output Voltage (volts) Output Voltage (volts) 12 Typical Output Overcurrent Characteristics AEH20G24 6 4 Vin=18V 3 Vin=24V 2 Vin=36V 1 0 2.4 Vin=18V 1.8 Vin=24V Vin=36V 1.2 0.6 0 3 6 9 12 15 0 18 7 14 21 28 Output Curent (amps) Output Curent (amps) Typical Output Overcurrent Characteristics AEH20F24 Typical Output Overcurrent Characteristics AEH10A24 6 Output Voltage (volts) 3.5 Output Voltage (volts) 9 Output Curent (amps) Typical Output Overcurrent Characteristics AEH10A24 2.8 Vin=18V 2.1 Vin=24V Vin=36V 1.4 5 4 Vin=18V 3 Vin=24V Vin=36V 2 1 0.7 0 6 12 18 24 30 0 USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 5 10 15 20 25 30 Output Curent (amps) Output Curent (amps) TEL: FAX: 6 Asia 852-2437-9662 852-2402-4426 -13www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Characteristic Curves (at 25 C ) Typical Input-Output Characteristics AEH10G24 Typical Input-Output Characteristics AEH10F24 2.5 Input Current (amps) Input Current (amps) 2 1.5 1 0.5 0 2 1.5 1 0.5 0 0 10 20 30 40 0 Input Voltage (volts) 40 Input Current (amps) 4 3 2 1 0 3 2 1 0 0 10 20 30 40 0 10 Input Voltage (volts) 20 30 40 Input Voltage (volts) Typical Input-Output Characteristics AEH20F24 Typical Input-Output Characteristics AEH20A24 8 Input Current (amps) 5 Input Current (amps) 30 Typical Input-Output Characteristics AEH20G24 4 4 3 2 1 0 6 4 2 0 0 10 20 30 40 0 USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 10 20 30 40 Input Voltage (volts) Input Voltage (volts) TEL: FAX: 20 Input Voltage (volts) Typical Input-Output Characteristics AEH10A24 Input Current (amps) 10 Asia 852-2437-9662 852-2402-4426 -14www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t T ransient response TEL: FAX: (24V rated input, variable load, at 25 C) Typical Transient Response to Step Load Change from 25%-50%-25%Iomax AEH10G24 Typical Transient Response to Step Load Change from 25%-50%-25%Iomax AEH10F24 Typical Transient Response to Step Load Change from 25%-50%-25%Iomax AEH10A24 Typical Transient Response to Step Load Change from 25%-50%-25%Iomax AEH20G24 Typical Transient Response to Step Load Change from 25%-50%-25%Iomax AEH20F24 Typical Transient Response to Step Load Change from 25%-50%-25%Iomax AEH20A24 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 -15www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t T ransient response TEL: FAX: (24V rated input, variable load, at 25 C) Typical Transient Response to Step Load Change from 75%-50%-75%Iomax AEH10G24 Typical Transient Response to Step Load Change from 75%-50%-75%Iomax AEH10F24 Typical Transient Response to Step Load Change from 75%-50%-75%Iomax AEH10A24 Typical Transient Response to Step Load Change from 50%-75%-50%Iomax AEH20G24 Typical Transient Response to Step Load Change from 50%-75%-50%Iomax AEH20F24 Typical Transient Response to Step Load Change from 75%-50%-75%Iomax AEH20A24 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 -16www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Characteristic Curves TEL: FAX: (24V rated input voltage, full load, at 25 C) Typical Start-Up from Power On AEH10G24 Typical Start-Up from Power On AEH10F24 Typical Start-Up from Power On AEH10A24 Typical Start-Up from Power On AEH20G24 Typical Start-Up from Power On AEH20F24 Typical Start-Up from Power On AEH20A24 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 -17www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Characteristic Curves TEL: FAX: (24V rated input voltage, full load, at 25 C) Typical Shut-down from Power Off AEH10G24 Typical Shut-down from Power Off AEH10F24 Typical Shut-down from Power Off AEH10A24 Typical Shut-down from Power Off AEH20G24 Typical Shut-down from Power Off AEH20F24 Typical Shut-down from Power Off AEH20A24 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 AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Characteristic Curves TEL: FAX: (24V rated input voltage, full load, at 25 C) Typical Start-Up Transient with Remote On/Off AEH10G24 Typical Start-Up Transient with Remote On/Off AEH10F24 Typical Start-UpTransient with Remote On/Off AEH10A24 Typical Start-UpTransient with Remote On/Off AEH20G24 Typical Start-UpTransient with Remote On/Off AEH20F24 Typical Start-UpTransient with Remote On/Off AEH20A24 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 AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Characteristic Curves TEL: FAX: (24V rated input voltage, full load, at 25 C) Typical Shut-down Transient with Remote On/Off AEH10G24 Typical Shut-downTransient with Remote On/Off AEH10F24 Typical Shut-downTransient with Remote On/Off AEH10A24 Typical Shut-downTransient with Remote On/Off AEH20G24 Typical Shut-downTransient with Remote On/Off AEH20F24 Typical Shut-downTransient with Remote On/Off AEH20A24 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 AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Characteristic Curves TEL: FAX: (24V rated input voltage, full load, at 25 C) Typical Output Ripple Voltage AEH10G24 Typical Output Ripple Voltage AEH10F24 Typical Output Ripple Voltage AEH10A24 Typical Output Ripple Voltage AEH20G24 Typical Output Ripple Voltage AEH20F24 Typical Output Ripple Voltage AEH20A24 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 AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Characteristic Curves TEL: FAX: (24V rated input voltage, full load, at 25 C) Overvoltage Protection AEH10G24 Overvoltage Protection AEH10F24 Overvoltage Protection AEH10A24 Overvoltage Protection AEH20G24 Overvoltage Protection AEH20F24 Overvoltage Protection AEH20A24 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 -22www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Pin Location The +Vin and -Vin input connection pins are located as shown in Figure 1. AEH 24Vin converters have a 2:1 input voltage range and can accept 18-36 Vdc. Care should be taken to avoid applying reverse polarity to the input which can damage the converter. Standard safety agency regulations require input fusing. Recommended fuse ratings for the AEH 24Vin Series are shown in Table 1. Table 1 Series Fuse Rating(24Vin) 50W 75W 100W 150W 10A 15A 20A 40A Top View 5.1 (0.2) 61.0 (2.4) 7.62 (0.3) +Vin +Vout CNT +Sense 10.16 (0.4) 10.16 (0.4) 7.62 (0.3) 15.24 (0.6) Trim 7.62 (0.3) Case -Sense -Vin -Vout 10.16 (0.4) 10.16 (0.4) Mounting Inserts M3 thru hole x4 4.8 (0.19) 48.26 (1.9) mm (inches) 57.9 (2.28) Length optional 5.8 (0.228) default 12.7 (0.5) 7- 1.0 (0.04) all pins except +Vo and -Vo Pin Length Option 4.80mm ! 0.5mm 0.189in. ! 0.020in. 3.80mm ! 0.25mm 0.150in. ! 0.010in. 2.80mm ! 0.25mm 0.110in. ! 0.010in. 5.8mm ! 0.5mm 0.228in. ! 0.02in. 2- 2.0 (0.09) only +Vo and -Vo Device Code Suffix -4 -6 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 determined by the power of the converter. Diodes should be rated as shown in Table1. 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. -8 none Fig.1. Dimensions Input Characteristic Fusing: The AEH 24Vin 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. If one of the input lines is connected to chassis ground, then the fuse must be placed in the other input line. TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 +Vin +Vin -Vin -Vin Fig.2. Reverse Polarity Protection Circuits Input Undervoltage Protection The AEH 24Vin series is 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. Asia 852-2437-9662 852-2402-4426 -23www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t 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 AEH 24Vin 2.5Vout series has an internal switching frequency of 180kHz 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/63V electrolytic capacitor is recommended for C1. +Vin C1 -Vin Control Function Two remote on/off options are available. Negative logic 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. Positive logic applying a voltage larger than 3V to the CNT pin will enable the output, and applying a voltage less than 1.2V will disable it. Positive logic, device code suffix " P " . Negative logic, device code suffix nothing is the factory-preferred. If the CNT pin is left open, the converter will default to " control off " operation in negative logic, but default to " control on " in positive logic. The maximum voltage that can be applied to the control pin is 15V. Fig.3. Ripple Rejection Input Filter CNT 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. L1, L2 is a 2mH common mode choke. 1uF Vin+ 4700pF 4700pF 4700pF CNT 1000pF 1uF L2 L1 220uF DC/DC + 1uF 1000pF 4700pF -Vin Fig.5. Simple Control 4700pF 2200uF RL 4700pF -Vin VinCase 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. TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 CNT -Vin Fig.8. Relay Control Asia 852-2437-9662 852-2402-4426 -24www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Input-Output Characteristic Case Grounding: For proper operation of the module, the case or baseplate of the AEH 24Vin module does not require a connection to a chassis ground. If the 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 AEH module is not in a metallic enclosure in a system, it may be advisable to directly ground the case to reduce electric field emissions. Leaving the case floating can help to reduce magnetic field radiation from common mode noise currents. If the case has to be grounded for safety or other reasons, an inductor can be connected to chassis at DC and AC line frequencies, but be left floating at switching frequencies. Under this condition, the safety requirements are met and the emissions are minimized. 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 non-SELV power system, Output Characteristic double or reinforced insulation must be provided in the power supply that isolates the input Minimum Load Requirements: from any hazardous voltages, including the ac There no minimum load required for the AEH mains. One Vi pin and one Vo pin are to be 24Vin series modules. grounded or both the input and output pins are TEL: FAX: to be kept floating. Single fault testing in the Remote Sensing: power supply must be performed in combina- The AEH 24Vin converter can remotely sense tion with the DC/DC power module to demon- both lines of its output which moves the effec- strate that the output meets the requirement for tive output voltage regulation point from the out- SELV. The input pins of the module are not put of the unit to the point of connection of the operator accessible. remote sense pins. This feature automatically Note: Do not ground either of the input pins of adjusts the real output voltage of the AEH the module, without grounding one of the output 24Vin in order to compensate for voltage drops pins. This may allow a non-SELV voltage to in distribution and maintain a regulated voltage appear between the output pin and ground. at the point of load. 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 -25www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t When the converter is supporting loads far Output Trimming: Trimming: away, or is used with undersized cabling, sig- Users can increase or decrease the output volt- nificant voltage drop can occur at the load. The age set point of a module by connecting an best defense against such drops is to locate the external resistor between the TRIM pin and load close to the converter and to ensure ade- either the SENSE (+ ) or SENSE ( - ) pins. The quately sized cabling is used. When this is not trim resistor should be positioned close to the possible, the converter can compensate for a module. If not using the trim feature, leave drop of up to 0.5V, through use of the sense the TRIM pin open. leads. Trimming up by more than 10% of the nominal When used, the + and - Sense leads should be output may damage the converter or trig the connected from the converter to the point of OVP protection. Trimming down more than load as shown in Figure 9 using twisted pair 10% can cause the converter to regulate wire. The converter will then regulate its output improperly. Trim down and trim up circuits and voltage at the point where the leads are con- the corresponding configuration are shown in nected. Care should be taken not to reverse the Figure 10 to Figure 15 next page. sense leads. If reversed, the converter will trig- Note that at elevated output voltages the ger the OVP protection and turn off. When not maximum power rating of the module used, the +Sense lead must be connected remains the same, and the output current with +Vo directly, and -Sense with -Vo. Also capability will decrease correspondingly. note that the output voltage and the remote sense voltage offset must be less than the min- Output Over-Current Protection: imum overvoltage trip point. Note that at ele- AEH 24Vin series DC/DC converters feature vated output voltages the maximum power foldback current limiting as part of their rating of the module remains the same, and Overcurrent Protection (OCP) circuits. When the output current capability will decrease output current exceeds 110 to 140% of rated correspondingly. current, such as during a short circuit condition, the output will shutdown immediately, and can tolerate short circuit conditions indefinitely. +Vout +Sense +S When the overcurrent condition is removed, the converter will automatically restart. Twisted Pair Load -Sense -S -Vout Fig.9. Sense Connections 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 -26www.astec.com VI(+) VO(+) ON/OFF SENSE(+) Radj-up CASE RLOAD TRIM VI(-) SENSE(-) VO(-) Vo(100+y) (100+2y) Radj-up = y 1.26y where y is the adjusting percentage of the voltage. Radj-up is in kohms. 0 < y < 10 270 240 210 180 150 120 90 60 30 0 0 2 VI(+) 90 80 70 60 50 40 30 20 10 0 3 4 5 6 7 8 9 10 VO(+) ON/OFF SENSE(+) CASE RLOAD TRIM Radj-down VI(-) SENSE(-) VO(-) 100 -2 y where y is the adjusting percentage of the voltage. Radj-down is in kohms. 0 < y < 10 Radj-down= 0 1 2 3 4 5 6 7 8 9 10 Fig.11. Resistor Selection for Trimming Up 2.5V Outputs 200 180 160 140 120 100 80 60 40 20 0 0 1 2 3 4 5 6 7 8 9 10 Fig.14. Circuit Configuration and Equation to Trim Down Output Voltage 100 90 80 70 60 50 40 30 20 10 0 % Change In Output Voltage y Fig.12. Resistor Selection for Trimming Up 3.3V Outputs TEL: FAX: 1 Fig.13. Resistor Selection for Trimming Up 5V Outputs 100 % Change In Output Voltage (y) Adjustment Resistor Value (k) 300 % Change In Output Voltage (y) Adjustment Resistor Value (k) Adjustment Resistor Value (k) Fig.10. Circuit Configuration and Equation to Trim Up Output Voltage Adjustment Resistor Value (k) AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 0 1 2 3 4 5 6 7 8 9 10 % Change In Output Voltage (y) Fig.15. Resistor Selection for Trimming Down Output Voltage Asia 852-2437-9662 852-2402-4426 -27www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t 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 16. The recommended value for the output capacitor C1 is 2,200F/10V. +Vout C1 Load -Vout 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 18. 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 19. Fig.16. Output Ripple Filter RLine RLine +Vout 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 15. The recommended component for C2 is 2200F/10V capacitor and connecting a 0.1F ceramic capacitor C1 in parallel generally. Load Load RLine -Vout RLine RLine Ground Loop RLine Fig. 18. Ground Loops RLine RLine +Vout Load +Vout C1 C2 -Vout Load RLine RLine -Vout Fig.17. Output Ripple Filter For a Distant Load 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 TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Load RLine Europe 44-(0)1384-842-211 44-(0)1384-843-355 Fig. 19. Single Point Ground Output Over-Voltage Over-Voltage Protection: The over-voltage protection has a separate feedback loop which activates when the output voltage is between 120% and 140% of the nominal output voltage. When an over-voltage condition occurs, a " turn off " signal was sent to the input of the module, and shut off the output. The module will restart after power on again. Asia 852-2437-9662 852-2402-4426 -28www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Parallel Power Distribution Figure 20 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 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 RL2 RL1 +Vout Load 1 Load -Vout RG2 RG1 Fig.20. Parallel Power Distribution RL = Lead Resistance Radial Power Distribution Radial power distribution is the preferred method of providing power to the load. Figure 21 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 RG1 Load 2 Load 3 RG2 RG3 -Vout RL = Lead Resistance RG = Ground Lead Resistance design when a purely radial design is not feasible. +Vout Europe 44-(0)1384-842-211 44-(0)1384-843-355 Load 2 Load 3 Load 4 RG2 RG3 -Vout RG4 RL = Lead Resistance RG = Ground Lead Resistance Fig. 22. Mixed Power Distribution Redundant Operation A common requirement in high reliability systems is to provide redundant power supplies. The easiest way to do this is to place two converters in parallel, providing fault tolerance but not load sharing. Oring diodes should be used to ensure that failure of one converter will not cause failure of the second. Figure 23 shows such an arrangement. Upon application of power, one of the converters will provide a slightly higher output voltage and will support the full load demand. The second converter will see a zero load condition and will "idle". If the first converter should fail, the second converter will support the full load. When designing redundant converter circuits, Shottky diodes should be used to minimize the forward voltage drop. The voltage drop across the Shottky diodes must also be considered when determining load voltage requirements. +Vout -Vout 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 USA 1-760-930-4600 1-760-930-0698 RL4 RL2 Load 1 RG1 Fig.21. Radial Power Distribution TEL: FAX: RL3 RL1 Load +Vout -Vout Fig. 23. Redundant Operation Asia 852-2437-9662 852-2402-4426 -29www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Thermal Management Technologies AEH 24V input series features high efficiency and the module have typical efficiency high up to 88% 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 case 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 case temperature of the module (Tc) as the method shown in Figure 24 can verify the proper cooling. Figure 24 shows the metal surface of the module and the pin locations. The module should work under 90C for the reliability of operation and TC must not exceed 100 C while operating in the final system configuration. The measurement can be made with a surface probe after the module has reached thermal equilibrium. If a heat sink is mounted to the case, make the measurement as close as possible to the indicated position. 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 include heat sinks 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 condi- TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 tions. Thermal management acts to transfer the heat 29.0 (1.14) 30.5 (1.2) VI (+) MEASURE CASE TEMPERATURE HERE VO (+) ON/OFF + SEN CASE - SEN VI (-) VO (-) TRIM Top View Dimensions: millimeters (inches) Fig.24. Case Temperature Measurement dissipated by the module to the surrounding environment. The amount of power dissipated by the module as heat (PD) is got by the equation 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- )/ 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 curve of AEH series are shown as figure 25 to figure 30. Asia 852-2437-9662 852-2402-4426 -30www.astec.com 5.5 8 5 7 4.5 4 3.5 3 Vin=18V Vin=24V 2.5 Power Dissipation (W) Power Dissipation (W) AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t 6 5 4 Vin=18V 3 Vin=24V Vin=36V Vin=36V 2 2 0 1 2 3 4 5 6 7 8 9 10 0 2 4 8 10 12 14 16 Fig.25. AEH10G24 Power Dissipation Curves 5.5 9 Power Dissipation (W) 10 5 4.5 4 3.5 3 Vin=18V 2.5 Vin=24V 8 7 6 5 Vin=18V 4 Vin=24V Vin=36V 0 1 2 3 4 5 6 7 8 9 Vin=36V 3 10 0 2 4 9 18 8 16 7 6 5 Vin=18V 4 Vin=24V Vin=36V 3 2 3 4 5 6 7 8 9 Fig.27. AEH20F24 Power Dissipation Curves USA 1-760-930-4600 1-760-930-0698 10 12 14 16 18 20 10 14 12 10 Vin=18V 8 Vin=24V Vin=36V 6 0 2 Europe 44-(0)1384-842-211 44-(0)1384-843-355 4 6 8 10 12 14 16 18 20 Output Current (A) Output Current (A) TEL: FAX: 8 Fig.29. AEH20G24 Power Dissipation Curves Power Dissipation (W) Power Dissipation (W) Fig.26. AEH10A24 Power Dissipation Curves 1 6 Output Current (A) Output Current (A) 0 20 Fig.28. AEH10F24 Power Dissipation Curves 6 2 18 Output Current (A) Output Current (A) Power Dissipation (W) 6 Fig.30. AEH20A24 Power Dissipation Curves Asia 852-2437-9662 852-2402-4426 -31www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Module Derating Experiment Setup From the experimental set up shown in figure 31, the derating curves as figure 32 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. FACING PWB Example 1. How to calculate the minimum airflow required to maintain a desired Tc? If a AEH20A24 module operates with a 24V line voltage, a 20 A output current, and a 40 C maximum ambient temperature, What is the minimum airflow necessary for the operating? Determine PD ( referenced Fig.30. ) with condition: VI = 24 V lO = 20 A Get: PD = 15 W And with TA = 40 C Determine airflow ( Fig.32. ): v = 1.5 m/s (300 ft./min.) PWB MODULE AIR VELOCITY AND AMBIENT TEMPERATURE MEASURED BELOW THE MODULE 76 (3.00) AIRFLOW 19 (0.75) Dimensions: millimeters (inches). Fig.31. Experiment Set Up 21 4.0 m/s (800 ft./min.) 3.0 m/s (600 ft./min.) 2.0 m/s (400 ft./min.) 1.5 m/s (300 ft./min.) 1.0 m/s (200 ft./min.) Power Dissipation , PD (W) 18 15 12 9 0.5 m/s (100 ft./min.) 6 0.1 m/s (20 ft./min.) Natural Convection 3 0 0 10 20 30 40 50 60 70 80 90 100 Local Ambient Temperature, T A (C) Fig.32. Forced Convection Power Derating without Heat Sink TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Convection Without Without Heat Sinks Heat transfer can be enhanced by increasing the airflow over the module. Figure 32 shows the maximum power that can be dissipated by the module. In the test, natural convection airflow was measured at 0.05 m/s to 0.1 m/s (10 ft./min. to 20 ft./min.). The 0.5 m/s to 4.0 m/s (100 ft./min. to 800 ft./min.) curves are tested with externally adjustable fans. The appropriate airflow for a given operating condition can be determined through figure 32. Europe 44-(0)1384-842-211 44-(0)1384-843-355 Example 2. How to calculate the maximum output power of a module in a certain convection and a max. TA? What is the maximum power output for a AEH20A24 operating at following conditions: VI = 24 V; v = 1.5 m/s (300 ft./min.); TA = 40 C. Determine PD ( Fig.32. ) PD = 15W Determine IO (Fig.30): IO = 20 A Calculate PO: Asia 852-2437-9662 852-2402-4426 -32www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t PO = (VO) x (IO) = 5 x 20 = 100 W Although the two examples above use 100 C as the maximum case temperature, for extremely high reliability applications, one may design to a lower case temperature as shown in Example 4 on page 35. Heat Sink Configuration Several standard heat sinks are available for the AEH 24Vin 50 W to 150 W modules as shown in Figure 33 to Figure 35. The heat sinks mount to the top surface of the module with screws torqued to 0.56 N-m (5 in.- 57.0 (2.24) 4.9(0.193) 11.8 (0.465) Dimensions: millimeters (inches). 89.1(3.51) lb). A thermally conductive dry pad or thermal grease is placed between the case and the heat sink to minimize contact resistance (typically 0.1 C/W to 0.3 C/W) and temperature differential. Nomenclature for heat sink configurations is as follows: WDxyyy40 where: x = fin orientation: longitudinal (L) or trans verse (T) yyy = heat sink height (in 100ths of inch) For example, WDT5040 is a heat sink that is transverse mounted (see Figure 35) for a 61 mm x 57.9 mm (2.4 in.x 2.28 in.) module with a heat sink height of 0.5 in. Fig.33. Non Standard Heatsink 1/2 IN. (WDL05040) 1 IN. (WDL10040) 61 (2.4) 1 1/2 IN. (WDL15040) 57.9 (2.28) Heatsink Mounting Advice A crucial part of the thermal design strategy is the thermal interface between the baseplate of the module and the heatsink. Inadequate measures taken here will quickly negate any other attempts to control the baseplate temperature. For example, using a conventional dry insulator can result in a case-heatsink thermal impedance of >0.5 C/W, while use one of the recommended interface methods (silicon grease or thermal pads available from Avansys) can Fig.34. Longitudinal Fins Heat Sink 1/2 IN. (WDT05040) 1 IN. (WDT10040) 57.9 (2.28) 1 1/2 IN. (WDT15040) 61 (2.4) Fig.35. Transverse Fins Heat Sink TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 Fig.36. Heat Sink Mounting Asia 852-2437-9662 852-2402-4426 -33www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t result in a case-heatsink thermal impedance around 0.1C/W. Natural Convection with Heat Sink The power derating for a module with the heat sinks ( shown as figure 25 to figure 30) in natural convection is shown in figure 35. In this test, natural convection generates airflow about 0.05 m/s to 0.1 m/s ( 10ft./min to 20ft./min ). Figure 37 can be used for heat-sink selection in natural convection environment. POWER DISSIPATION, PD (W) 35 30 1 1/2 in. 1 in. 1/2 in. 1/4 in. NONE 25 20 15 10 5 0 0 10 20 30 40 50 60 70 80 90 100 Basic Thermal Model There is another approach to analyze module thermal performance, to model the overall thermal resistance of the module. This presentation method is especially useful when considering heat sinks. The following equation can be used to calculate the total thermal resistance . RCA = TC, max / PD Where RCA is the module thermal resistance; TC, max is the maximum case temperature rise; PD is the module power dissipation. In this model, PD, TC, max, and RCA are equals to current flow, voltage drop, and electrical resistance, respectively, in Ohm's law, as shown in Figure 38. Also, TC, max is defined as the difference between the module case temperature (TC) and the inlet ambient temperature (TA). TC, max = TC TA Where TC is the module case temperature; TA is the inlet ambient temperature. LOCAL AMBIENT TEMPERATURE, TA (C) Fig.37. Heat Sink Power Derating Curves, Natural Convection Example 3. How to select a heat sink? What heat sink would be appropriate for a AVE100-24S05 in a natural convection environment at nominal line, 2/3 load, and maximum ambient temperature of 40C? Determine PD ( referenced Fig.30. ) with condition: VI = 24 V IO = 2/3 (20) = 13 A TA = 40 C Get: PD = 10.5 W Determine Heat Sink (Fig.37.): no heat sink allows up to TA = 30 C 1/4 in. allows up to TA = 40 C TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Europe 44-(0)1384-842-211 44-(0)1384-843-355 BMPM PD = BMPM THERMAL RESISTANCE Fig.38. Basic Thermal Resistance Model For AEH 24Vin Series 50W to 150W converters, the module's thermal resistance values versus air velocity have been determined experimentally and shown in figure 39. The highest values on each curve represents the point of natural convection. Figure 39 is used for determining thermal performance under various conditions of airflow and heat sink configurations. Asia 852-2437-9662 852-2402-4426 -34www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Case-Ambient Thermal Resistance R CA (C/W) 8 7 1 in. HEAT SINK 1/2 in. HEAT SINK 1/4 in. HEAT SINK NO HEAT SINK 6 5 4 3 2 1 0 0 0.5 (100) 1.0 (200) 1.5 (300) 2.0 (400) 2.5 (500) 3.0 (600) Air Velocity m/s (ft./min.) Fig.39. Case-to-Ambient Thermal Resistance Curves; Either Orientation Example 4. How to determine the allowable minimum airflow to heat sink combinations necessary for a module under a desired Tc and a certain condition? Although the maximum case temperature for the AEH Series converters is 100 C, you can improve module reliability by limiting Tc,max to a lower value. How to decide? For example, what is the allowable minimum airflow for AEH 100W heat sink combinations at desired Tc of 80 C? The working condition is as following: VI = 24 V, IO = 20 A, TA = 40 C Determine PD ( Fig.30. ) PD = 15 W Then solve RCA: RCA = TC, / PD RCA = (TC - TA) / PD RCA = (80 - 40) / 15 = 2.7C/W determine air velocity from figure 39: If no heat sink: v = 3 m/s (600 ft./min.) If 1/4 in. heat sink: v = 2 m/s (400 ft./min.) If 1/2 in. heat sink: v = 1.4 m/s (280 ft./min.) If 1 in. heat sink: v = 0.5 m/s (100 ft./min.) TEL: FAX: USA 1-760-930-4600 1-760-930-0698 Example 5. How to determine case temperature ( Tc ) for the various heat sink configurations at certain air velocity? What is the allowable Tc for AEH 24Vin 100W heat sink configurations at desired air velocity of 2.0 m/s, and it is operating at a 24 V line voltage, a 20 A output current, a 40 C maximum ambient temperature? Determine PD ( Fig.30. ) with condition: VI = 24 V, IO = 20 A, TA = 40 C, v = 2.0 m/s (400 ft./min.). Get: PD = 15 W Determine TC: TC = (RCA x PD) + TA Determine the corresponding thermal resistances ( RCA ) from Figure 39 : No heat sink: RCA = 3.8 C/W TC = (3.8 x 15) + 40 = 97 C 1/4 in. heat sink: RCA = 2.8 C/W TC = (2.8 x 15) + 40 = 82 C 1/2 in. heat sink: RCA = 2.0 C/W TC = (2.0 x 15) + 40 = 70 C 1 in. heat sink: RCA = 1.2 C/W TC = (1.2 x 15) + 40 = 58 C In this configuration, the heat sink would not need and the power module does not exceed the maximum case temperature of 100 C. max Europe 44-(0)1384-842-211 44-(0)1384-843-355 AEH 24Vin Series Mechanical Considerations Installation Although AEH 24Vin 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 Asia 852-2437-9662 852-2402-4426 -35www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t component life spans. Top View Soldering AEH 24Vin series converters are compatible with standard wave soldering techniques. When wave soldering, the converter pins should be preheated for 20-30 seconds at 110 C, and wave soldered at 260C for less than 10 seconds. When hand soldering, the iron temperature should be maintained at 425C 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. 5.1 (0.2) 61.0 (2.4) 7.62 (0.3) +Vin +Vout CNT +Sense 10.16 (0.4) 10.16 (0.4) 7.62 (0.3) 15.24 (0.6) Trim 7.62 (0.3) Case -Sense -Vin -Vout 10.16 (0.4) 10.16 (0.4) Mounting Inserts M3 thru hole x4 4.8 (0.19) 48.26 (1.9) mm (inches) 57.9 (2.28) Length optional 5.8 (0.228) default 12.7 (0.5) 7- 1.0 (0.04) all pins except +Vo and -Vo MTBF: Pin Length Option The MTBF, calculated in accordance with Bellcore TR-NWT-000332 is 1,880,000 hours. Obtaining this MTBF in practice is entirely possible. If the ambient air temperature is expected to exceed +25C, then we also advise a heatsink on the AEH, oriented for the best possible cooling in the air stream. 2- 2.0 (0.09) only +Vo and -Vo Device Code Suffix 4.80mm ! 0.5mm 0.189in. ! 0.020in. 3.80mm ! 0.25mm 0.150in. ! 0.010in. 2.80mm ! 0.25mm 0.110in. ! 0.010in. 5.8mm ! 0.5mm 0.228in. ! 0.02in. -4 -6 -8 none Mechnical chart Avansys can supply replacements for converters from other manufacturers, or offer custom solutions. Please contact the Avansys factory 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 -36www.astec.com AEH 24V Input Half-Brick Series Power Converters 2 . 5 V, 3 . 3 V, 5 V O u t p u t , 5 0 - 1 5 0 Wa t t Recommend Hole Pattern 57.9 (2.28) Max 4.8 (0.19) 48.3 (1.90) I +Vin 35.56 (1.400) 50.8 (2.00) Control 48.26 (1.900) +VO 35.56 (1.400) +Sense 25.40 (1.000) Trim 25.40 (1.000) Case 10.16 (0.400) -Vin -Sense 17.78 10.16 (0.700) (0.400) 61.0 (2.40) Max -VO 5.1 (0.20) 12.7 (0.50) Mounting Inserts Module Outline 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 -37www.astec.com