AVO75 Series DC/DC Converter TRN AVO75 Series DC/DC Converter Technical Reference Notes Industry Standard Eighth Brick: 36~75V Input, 1.2V~12V Single Output Features * * * * * Industry standard eighth brick: 2.28" x 0.9'' x 0.34'' Options * * Choice of positive logic or negative logic for CNT function Choice of short pins or long pins Description * * * * * * * * * * * Delivers up to 25A output current Industry standard eighth brick foot print 57.9mm x 22.9mm x 8.5mm (2.28" x 0.9" x 0.34") Basic isolation Ultra high efficiency: 92% at 5V full load (Vin = 48Vdc) Improved thermal performance: full load at 55C at 1m/s (200LFM) for 5Vo High power density Low output noise 2:1 wide input voltage of 36V-75V CNT function Remote sense Trim function: +10%/-20% Input under-voltage lockout Output over-current protection Output over-voltage protection Over-temperature protection RoHS compliant The AVO75 series DC/DC converter is a new open frame DC/DC converter for optimum efficiency and power density. The series provides up to 25A output current in an industry standard eighth brick, which makes it an ideal choice for small space, high current and low voltage applications. The AVO75 series uses an industry standard eighth brick: 57.9mm x 22.9mm x 8.9mm (2.28" x 0.9" x 0.35") and standard pin-out configuration, provides CNT and trim functions. AVO75 series can provide 1.2V ~ 12V single output, and outputs are isolated from inputs. The series can achieve ultra high efficiency, and for most applications, a heat sink is not required. TEL: (86) 755-86010808 BOM: 31020683 www.emersonnetworkpower.com.cn DATE: 2008-12-03 1/32 REV1.3 AVO75 Series DC/DC Converter TRN Module Numbering AVO 75 - 48 S 1V5 P - 4 Pin length CNT logic, P---positive logic control, default is negative logic control . Output rated voltage: 1V2--1.2V, 1V5--1.5V, 1V8--1.8V, 2V5--2.5V, 3V3--3.3V, 05--5V, 12--12V Output number: S ---single output, D---dual output Input rated voltage Output rated power Series name TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 2/32 AVO75 Series DC/DC Converter TRN Electrical Specifications Unless otherwise indicated, specifications apply over all operating input voltage and temperature conditions. Standard test condition on a single unit is as follows: Tc (board): 25 C +Vin: 48V 2% -Vin: return pin for +Vin CNT: connected to -Vin for negative logic open for positive logic +Vout: -Vout: +Sense: -Sense: Trim (Vadj): connected to load connected to load (return) connected to +Vout connected to -Vout open Input Specifications Parameter Symbol Min Typ Max Unit VI 36 48 75 VDC II,max - - 2.5 A Input Reflected-ripple Current (5Hz to 20MHz, 12H source impedance, TA = 25 C) II - - 20 mAp-p Supply Voltage Rejection (1kHz) - 50 60 - dB Operating Input Voltage Maximum Input Current (VI = 0 to VI,max, Io = Io,max) Caution: This power module is not internally fused. An input line fuse must always be used. TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 3/32 AVO75 Series DC/DC Converter TRN Absolute Maximum Ratings Stresses in excess of the absolute maximum ratings can cause permanent damage to the device. These are absolute stress ratings only. Functional operation of the device is not implied at these or any other conditions in excess of those given in the operational sections of the IPS. Exposure to absolute maximum ratings for extended periods can adversely affect device reliability. Parameter Device Symbol Min Typ Max Unit All VI 0 - 75 Vdc All VI, trans 0 - 100 Vdc All Ta -40 - 85 C Operating Board Temperature All Tc - - 100 C Storage Temperature All TSTG -55 - 125 C Operating Humidity All - - - 85 % All - 2000 Vdc Continuous Input Voltage Transient (100ms) Operating Ambient Temperature (See Thermal Consideration) Basic Input-Output Isolation (Conditions: 1mA for 60 sec, slew rate of 1500V/10sec) Output Power TEL: (86) 755-86010808 1.2V 30 1.5V 37.5 1.8V 45 2.5V Po,max 0 - 62.5 3.3V 66 5V 75 12V 75 www.emersonnetworkpower.com.cn W 4/32 AVO75 Series DC/DC Converter TRN Output Specifications Parameter Output ripple and noise peak-to-peak (5Hz to 20MHz) (across 1F @50V, X7R ceramic capacitor & 470F @25V LOW ESR aluminum capacitor) External load capacitance Output voltage setpoint (VI=VI,min to VI,max: Io=Io,max; Ta=25C) Output regulation Line (VI,min to VI,max) TEL: (86) 755-86010808 Device Symbol Min Typ 1.2V 50 1.5V 55 1.8V 45 2.5V - - 50 3.3V 50 5V 55 12V 55 Max Unit - mVp-p 1.2V 10,000 1.5V 10,000 1.8V 10,000 2.5V - 220 470 10,000 3.3V 10,000 5V 5000 12V 1000 1.2V 1.18 1.2 1.22 1.5V 1.48 1.5 1.52 1.8V 1.77 1.8 1.83 2.46 2.5 2.54 3.3V 3.25 3.3 3.35 5V 4.95 5 5.05 12V 11.85 12 12.15 2.5V Vo,set 1.2V 1 1.5V 1 1.8V 1 2.5V - - 1 3.3V 1 5V 4 12V 9 www.emersonnetworkpower.com.cn - F Vdc mV 5/32 AVO75 Series DC/DC Converter TRN Parameter Load (Io,min to Io,max) Temperature (Tc=-40 C to +100C) Rated output current Output current-limit inception (hiccup) Efficiency (VI=VI,nom; 100%Io,max ; TA=25C) Efficiency (VI=VI,nom ; 50%Io,max; Ta=25C) TEL: (86) 755-86010808 Device Symbol Min Typ 1.2V 1 1.5V 1 1.8V 1 2.5V - - 1 3.3V 1 5V 5 12V 5 All - - - Max Unit - mV 0.02 %Vo/C 1.2V, 25 1.5V 25 1.8V 25 2.5V Io 0 - 25 3.3V 20 5V 15 12V 6.3 1.2V 28 35 1.5V 28 35 1.8V 28 35 2.5V Io 28 - 35 3.3V 22 28 5V 16.5 21 12V 6.9 10 1.2V 88 1.5V 87 1.8V 89 2.5V - - 90.5 3.3V 91 5V 92 12V 91 1.2V 87 1.5V 88 1.8V 88.5 2.5V - - 89.5 3.3V 91 5V 91 12V 90 www.emersonnetworkpower.com.cn A A - % - % 6/32 AVO75 Series DC/DC Converter TRN Output Specifications (Cont) Parameter Device Load change from Io = 50% to 75% to 50% Io,max Symbol Min Typ 1.2V 60 1.5V 50 1.8V 50 2.5V - 60 3.3V 85 5V 110 Dynamic response 12V 150 (Io/t=1A/10s, VI=VI,nom; Ta=25C) 1.2V 300 1.5V 115 1.8V 125 Peak deviation settling Time (to Vo,nom) Load change from Io=50% to 75% to 50% Io,max 2.5V - 70 3.3V 70 5V 120 12V 120 1.2V 130 1.5V 130 1.8V 120 2.5V - 170 3.3V 130 Dynamic response 5V 130 (Io/t=1A/1s; 12V 120 1.2V 300 1.5V 100 1.8V 115 VI=VI,nom; Ta=25C, additional 220F load capacitor) Peak deviation settling time (to Vo,nom) 2.5V Max - 150 3.3V 80 5V 130 12V 320 Unit mV - sec - mv - sec 20 msec Turn-On time (Io=Io,max; Vo within 1%) All - - - Output voltage overshoot (Io=Io,max; Ta=25C) All - - 0 %Vo Switching frequency All - 310 kHz TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 7/32 AVO75 Series DC/DC Converter TRN Feature Specifications Parameter Device Symbol Min Typ Max Unit Logic low All -0.7 - 1.2 V Logic high All 3.5 - 12 V Enable pin current Logic low All - - 1.0 mA (leakage current, @10V) Logic high All - - - A 80 - 110 %Vo Enable pin voltage Output voltage adjustment range Output over-voltage (hiccup) Over-temperature protection (auto-recovery) All* - 1.2V 1.4 2.0 1.5V 1.8 2.5 1.8V 2.2 3.0 2.5V Vo,clamp 3.0 - 3.8 V 3.3V 3.9 5.0 5V 6.0 7.5 12V 14.4 18 All 110 120 135 C Under-voltage Lockout Turn-on point All - 31 34 36 V Turn-off point All - 30 33 35 V AVO75-48S12-6/D under-voltage lockout Turn-on point All - 34.8 37 38 V Turn-off point All - 33.8 35.5 37 V Isolation capacitance All - - 1000 - PF Isolation resistance All - 10 - - M Calculated MTBF (Io=Io,max; Tc=25C) All - - 2,500,000 - Hours Weight All - - - 30 g(oz.) Note: Output voltage adjustment rang of 12V module is 90% to 110%. TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 8/32 AVO75 Series DC/DC Converter TRN Characteristic Curves 90 85 85 80 80 Vin=36V 75 Vin=48V Vin=75V 70 0 5 10 15 20 75 Efficiency (%) Effiency(%) 90 70 65 36V 48V 75V 60 25 55 Load(A) 0 5 10 15 20 25 Load (A) Fig. 1 Typical efficiency of AVO75-48S1V2 Fig. 2 Typical efficiency of AVO75-48S1V5 95 90 Effiency(%) Effiency(%) 90 85 80 Vin=36V 75 5 10 15 20 Vin=36V Vin=48V Vin=75V Vin=75V 0 80 75 Vin=48V 70 85 70 25 0 5 10 Load(A) Fig. 3 20 25 Load(A) Typical efficiency of AVO75-48S1V8 Fig. 4 95 Typical efficiency of AVO75-48S2V5 95 90 Effiency(%) 90 Ef f iciency(%) 15 85 80 36V 48V 75V 75 2 4 6 8 10 12 14 16 18 85 80 Vin=36V 75 Vin=48V Vin=75V 70 20 0 3 6 Typical efficiency of AVO75-48S3V3 TEL: (86) 755-86010808 12 15 Load(A) Load (A) Fig. 5 9 Fig. 6 Typical efficiency of AVO75-48S05 www.emersonnetworkpower.com.cn 9/32 AVO75 Series DC/DC Converter TRN 95 Effiency(%) 90 85 80 Vin=36V Vin=48V 75 Vin=75V 70 0 1 2 3 4 5 6 Output current(A) Typical efficiency of AVO75-48S12 1.4 1.2 1.6 1 0.8 0.6 0.4 1.2 1.4 0.2 0 0 Fig. 8 5 10 15 20 25 Output Current (A) 30 35 Output voltage (V) Output Voltage (V) Fig. 7 1 0.8 0.6 0.4 0.2 0 0 Typical output over-current of AVO75-48S1V2 Fig. 9 5 10 15 20 25 Output current (A) 30 35 40 Typical output over-current of AVO75-48S1V5 Output Voltage (V) Output Voltage (V) 3 1.8 1.5 1.2 0.9 0.6 0.3 2 1.5 1 0.5 0 0 0 Fig. 10 2.5 5 10 15 20 25 Output Current (A) 30 Typical output over-current of AVO75-48S1V8 TEL: (86) 755-86010808 0 35 Fig. 11 5 10 15 20 25 Output Current (A) 30 35 Typical output over-current of AVO75-48S2V5 www.emersonnetworkpower.com.cn 10/32 3.5 6 3 5 Output Voltage (V) Output VoltageV AVO75 Series DC/DC Converter TRN 2.5 2 1.5 1 0.5 4 3 2 1 0 0 0 0 5 10 15 20 25 30 35 4 8 12 Output Current (A) 40 16 20 Output Current A Fig. 12 Typical output over-current of AVO75-48S3V3 Fig. 13 Typical output over-current of AVO75-48S05 14 Output Voltage (V) 12 10 8 6 4 2 0 0 Fig. 14 2 4 6 Output Current (A) 10 Typical output over-current of AVO75-48S12 7 5 6 4 3 2 Vin=36V 1 Vin=48V Vin=75V 0 0 5 10 15 20 25 Power dissipation (W) Dissipation(W) 8 5 4 3 2 36V 48V 75V 1 0 0 Load(A) 5 10 15 20 25 Load (A) Fig. 15 Typical power dissipation of AVO75-48S1V2 TEL: (86) 755-86010808 Fig. 16 Typical power dissipation of AVO75-48S1V5 www.emersonnetworkpower.com.cn 11/32 7 6 5 4 3 2 1 0 9 8 7 Dissipation(W) Dissipation(W) AVO75 Series DC/DC Converter TRN Vin=36V 0 5 10 15 6 5 4 3 Vin=48V 2 Vin=75V 1 20 Vin=36V Vin=48V Vin=75V 0 25 0 5 10 Load(A) Fig. 17 Fig. 18 8 25 Typical power dissipation of AVO75-48S2V5 8 Dissipation(W) Pow er Dissipation (W) 20 Load(A) Typical power dissipation of AVO75-48S1V8 6 4 2 36V 48V 75V 0 6 4 Vin=36V 2 Vin=48V Vin=75V 0 0 2 4 6 8 10 12 14 16 18 3 6 20 9 12 15 Load(A) Load (A) Fig. 19 15 Typical power dissipation of AVO75-48S3V3 Fig. 20 Typical power dissipation of AVO75-48S05 Dissipation(W) 10 8 6 4 Vin=36V 2 Vin=48V Vin=75V 0 0 1 2 3 4 5 6 Output current(A) Fig. 21 TEL: (86) 755-86010808 Typical power dissipation of AVO75-48S12 www.emersonnetworkpower.com.cn 12/32 AVO75 Series DC/DC Converter TRN Fig. 22 AVO75-48S1V2 typical transient response to step decrease in load from 50% to 25% of full load, room temperature, 48Vdc input Fig. 23 AVO75-48S1V2 typical transient response to step increase in load from 50% to 75% of full load, room temperature, 48Vdc input Fig. 24 AVO75-48S1V5 typical transient response to step decrease in load from 50% to 25% of full load, room temperature, 48Vdc input Fig. 25 AVO75-48S1V5 typical transient response to step increase in load from 50% to 75% of full load, Fig. 26 AVO75-48S1V5 typical transient response to step decrease in load from 50% to 25% of full load, Fig. 27 AVO75-48S1V5 typical transient response to step increase in load from 50% to 75% of full load, room temperature, 48Vdc input (Io/t=0.1A/1s) room temperature, 48Vdc input (Io/t=0.1A/1s) TEL: (86) 755-86010808 room temperature, 48Vdc input (Io/t=1A/1s) www.emersonnetworkpower.com.cn 13/32 AVO75 Series DC/DC Converter TRN Fig. 28 AVO75-48S1V5 typical transient response to step decrease in load from 50% to 25% of full load, Fig. 29 AVO75-48S1V5 typical transient response to step increase in load from 50% to 75% of full load, room temperature, 48Vdc input (Io/t=1A/1s) room temperature, 48Vdc input (Io/t=1A/1s) Fig. 30 AVO75-48S1V8 typical transient response to step decrease in load from 50% to 25% of full load, Fig. 31 AVO75-48S1V8 typical transient response to step increase in load from 50% to 75% of full load, room temperature, 48Vdc input (Io/t=0.1A/1s) room temperature, 48Vdc input (Io/t=0.1A/1s) Fig. 32 AVO75-48S1V8 typical transient response to step decrease in load from 50% to 25% of full load, Fig. 33 AVO75-48S1V8 typical transient response to step increase in load from 50% to 75% of full load, room temperature, 48Vdc input (Io/t=1A/1s) room temperature, 48Vdc input (Io/t=1A/1s) TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 14/32 AVO75 Series DC/DC Converter TRN Fig. 34 AVO75-48S2V5 typical transient response to step decrease in load from 50% to 25% of full load, Fig. 35 AVO75-48S2V5 typical transient response to step increase in load from 50% to 75% of full load, room temperature, 48Vdc input (Io/t=0.1A/1s) room temperature, 48Vdc input (Io/t=0.1A/1s) Fig. 36 AVO75-48S2V5 typical transient response to step decrease in load from 50% to 25% of full load, Fig. 37 AVO75-48S2V5 typical transient response to step increase in load from 50% to 75% of full load, room temperature, 48Vdc input (Io/t=1A/1s) room temperature, 48Vdc input (Io/t=1A/1s) Fig. 38 AVO75-48S3V3 typical transient response to step decrease in load from 50% to 25% of full load, Fig. 39 AVO75-48S3V3 typical transient response to step increase in load from 50% to 75% of full load, room temperature, 48Vdc input (Io/t=0.1A/1s) room temperature, 48Vdc input (Io/t=0.1A/1s) TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 15/32 AVO75 Series DC/DC Converter TRN Fig. 40 AVO75-48S3V3 typical transient response to step decrease in load from 50% to 25% of full load, Fig. 41 AVO75-48S3V3 typical transient response to step increase in load from 50% to 75% of full load, room temperature, 48Vdc input (Io/t=1A/1s) room temperature, 48Vdc input (Io/t=1A/1s) Fig. 42 AVO75-48S05 typical transient response to step decrease in load from 50% to 25% of full load, Fig. 43 AVO75-48S05 typical transient response to step increase in load from 50% to 75% of full load, room temperature, 48Vdc input (Io/t=0.1A/1s) room temperature, 48Vdc input (Io/t=0.1A/1s) Fig. 44 AVO75-48S05 typical transient response to step decrease in load from 50% to 25% of full load, Fig. 45 AVO75-48S05 typical transient response to step increase in load from 50% to 75% of full load, room temperature, 48Vdc input (Io/t=1A/1s) room temperature, 48Vdc input (Io/t=1A/1s) TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 16/32 AVO75 Series DC/DC Converter TRN Fig. 46 AVO75-48S12 typical transient response to step decrease in load from 50% to 25% of full load, Fig. 47 AVO75-48S12 typical transient response to step increase in load from 50% to 75% of full load, room temperature, 48Vdc input (Io/t=0.1A/1s) room temperature, 48Vdc input (Io/t=0.1A/1s) Fig. 48 AVO75-48S12 typical transient response to step decrease in load from 50% to 25% of full load, Fig. 49 AVO75-48S12 typical transient response to step increase in load from 50% to 75% of full load, room temperature, 48Vdc input (Io/t=1A/1s) room temperature, 48Vdc input (Io/t=1A/1s) Fig. 50 Typical output ripple voltage of AVO75-48S1V2 room temperature, Io=Io,max Fig. 51 Typical output ripple voltage of AVO75-48S1V5 room temperature, Io=Io,max TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 17/32 AVO75 Series DC/DC Converter TRN Fig. 52 Typical output ripple voltage of AVO75-48S1V8 room temperature, Io=Io,max Fig. 53 Typical output ripple voltage of AVO75-48S2V5 room temperature, Io=Io,max Fig. 54 Typical output ripple voltage of AVO75-48S3V3 room temperature, Io=Io,max Fig. 55 Typical output ripple voltage of AVO75-48S05 room temperature, Io=Io,max Fig. 56 Typical output ripple voltage of AVO75-48S12 room temperature, Io=Io,max TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 18/32 AVO75 Series DC/DC Converter TRN Fig. 57 Fig. 59 Fig. 61 AVO75-48S1V2 typical start-up from power on AVO75-48S1V5 typical start-up from power on AVO75-48S1V8 typical start-up from power on TEL: (86) 755-86010808 Fig. 58 AVO75-48S1V2 typical start-up from CNT on Fig. 60 AVO75-48S1V5 typical start-up from CNT on Fig. 62 AVO75-48S1V8 typical start-up from CNT on www.emersonnetworkpower.com.cn 19/32 AVO75 Series DC/DC Converter TRN Fig. 63 AVO75-48S2V5 typical start-up from power on Fig. 65 Fig. 67 AVO75-48S3V3 typical start-up from power on AVO75-48S05 typical start-up from power on TEL: (86) 755-86010808 Fig. 64 AVO75-48S2V5 typical start-up from CNT on Fig. 66 AVO75-48S3V3 typical start-up from CNT on Fig. 68 AVO75-48S05 typical start-up from CNT on www.emersonnetworkpower.com.cn 20/32 AVO75 Series DC/DC Converter TRN Fig. 69 AVO75-48S12 typical start-up from power on TEL: (86) 755-86010808 Fig. 70 AVO75-48S12 typical start-up from CNT on www.emersonnetworkpower.com.cn 21/32 AVO75 Series DC/DC Converter TRN Feature Description CNT Function The converter is equipped with a primary ON/OFF pin used to remotely turn the converter on or off via a system signal. Two CNT logic options are available. For the positive logic model a system logic low signal will turn the unit off. For the negative logic model a system logic high signal will turn the converter off. For negative logic models where no control signal will be used the ON/OFF pin should be connected directly to -Vin to ensure proper operation. For positive logic models where no control signal will be used the ON/OFF pin should be left unconnected. The following Fig. shows a few simple CNT circuits. CNT CNT -Vin -Vin Simple CNT Transistor CNT CNT CNT -Vin -Vin Isolated CNT Fig. 71 Relay CNT CNT circuits drops in distribution and maintain a regulated voltage at the point of load. When the converter is supporting loads far away, or is used with undersized cabling, significant voltage drop can occur at the load. The best defense against such drops is to locate the load close to the converter and to ensure adequately sized cabling is used. When this is not possible, the converter can compensate for a drop of up to 10%Vo, through use of the sense leads. When used, the + Sense and - Sense leads should be connected from the converter to the point of load as shown in Fig. 72, using twisted pair wire, or parallel pattern to reduce noise effect. The converter will then regulate its output voltage at the point where the leads are connected. Care should be taken not to reverse the sense leads. If reversed, the converter will trigger OVP protection. When not used, the +Sense lead must be connected with +Vo, and -Sense with -Vo. Although the output voltage can be increased by both the remote sense and by the trim, the maximum increase for the output voltage is not the sum of both. The maximum increase is the larger of either the remote sense or the trim. Note that at elevated output voltages the maximum power rating of the module remains the same, and the output current capability will decrease correspondingly. Remote Sense +Vo The AVO75 converter can remotely sense both lines of its output which moves the effective output voltage regulation point from the output terminals of the unit to the point of connection of the remote sense pins. This feature automatically adjusts the real output voltage of the AVO75 in order to compensate for voltage TEL: (86) 755-86010808 +S +Sense Twisted pair Load -Sense -S -Vo Fig. 72 Sense connections www.emersonnetworkpower.com.cn 22/32 AVO75 Series DC/DC Converter TRN Trim =(1.98-1.8)x100/1.8=10 The +Vo output voltage of the AVO75 series can be trimmed with the trim pin provided. Applying a resistor to the trim pin through a voltage divider from the output will cause the +Vo output to increase by up to 10%or decrease by up to 20%. Trimming up by more than 10% of the nominal output may activate the OVP circuit or damage the converter. Trimming down more than 20% can cause the converter to regulate improperly. If the trim pin is not needed, it should be left open. Radj -up = 5.1 x 1.8 x (100 + 10 ) 510 - - 10.2(k ) 1.225 x 10 10 Radj -up = 21.23( k ) Trim down With an external resistor between the TRIM and -SENSE pins, the output voltage set point decreases (see Fig. 74). Vo(+) Vi(+) SENSE(+) CNT TRIM Trim up With an external resistor connected between the TRIM and +SENSE pins, the output voltage set point increases (see Fig. 73). Vi(+) SENSE(+) Radj-up TRIM Vi(-) SENSE(-) Vi(-) Vo(-) Fig. 74 Trim down circuit The following equation determines the required external-resistor value to obtain a percentage output voltage change of 1%. For output voltage: 1.2V ~ 12V Vo(+) CNT RLOAD Radj-down RLOAD SENSE(-) Radj -down = Vo(-) 510 - 10.2(k) % Note: = (Vnom-Vo) % 100/Vnom Fig. 73 Trim up circuit The following equation determines the required external-resistor value to obtain a percentage output voltage change of 1%. For Output Voltage: 1.5V ~ 12V 5.1x Vnom x (100 + % ) 510 Radj -up = - - 10.2(k) 1.225 x % % For output voltage: 1.2V 5.1x Vnom x (100 + % ) 510 Radj -up = - - 10.2(k) 0. 6 x % % Note: =(Vnom-Vo)x100/Vnom Vtrim tolerance: < 2%, Radj tolerance: 1% For example: trim up the output of Vtrim tolerance: <2%, Radj tolerance: 1% For example: trim down the output of AVO75-48S1V8 to 1.62V. =(1.8-1.62)x100/1.8=10 Radj -down = 510 - 10.2(k) 10 Radj - down = 40.8(k) Although the output voltage can be increased by both the remote sense and by the trim, the maximum increase for the output voltage is not the sum of both. The maximum increase is the larger of either the remote sense or the trim. AVO75-48S1V8 to 1.98V. TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 23/32 AVO75 Series DC/DC Converter TRN Note that at elevated output voltages the maximum power rating of the module remains the same, and the output current capability will decrease correspondingly. Minimum Load Requirements There is no minimum load requirement for the AVO75 series modules. Output Capacitance High output current transient rate (high di/dt) of changing loads might require high values of output capacitance to supply the instantaneous energy requirement to the load. To minimize the output voltage transient drop during this transient, low Equivalent Series Resistance (ESR) capacitors may be required, since a high ESR will produce a correspondingly higher voltage drop during the current transient. 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 C1 across the output as shown in Fig.75. The recommended value for the output capacitor C1 is 470F. +Vout C1 Load +Vout Load C1 C2 -Vout Fig. 76 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 10F tantalum or ceramic 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 Fig.77. Multiple ground points can gave slightly different potentials 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 Fig.78. -Vout Fig. 75 +Vo Output ripple filter 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 C1 can be added across the load, with a 1F ceramic capacitor C2 in parallel generally as shown in Fig. 76. TEL: (86) 755-86010808 RLine RLine Load Load -Vo RLine RLine RLine Ground R Loop Fig. 77 www.emersonnetworkpower.com.cn Ground loops 24/32 AVO75 Series DC/DC Converter TRN +Vo RLine Load -Vo over-temperature condition is removed, the converter will automatically restart. RLine RLine Load RLine Design Consideration RLine Typical Application Fig. 78 Single point ground F1 Output Over-current Pro tection +Vin Vin Cin AVO75 series DC/DC converters feature foldback current limiting as part of their Over-current Protection (OCP) circuits. When output current exceeds 110 to 140% of rated current, such as during a short circuit condition, the module will work on intermittent mode, also can tolerate short circuit conditions indefinitely. When the over-current condition is removed, the converter will automatically restart. Output Over-Voltage Protection The output over-voltage protection consists of circuitry that monitors the voltage on the output terminals. If the voltage on the output terminals exceeds the over voltage protection threshold, then the module will work on intermittent mode. When the over-voltage condition is removed, the converter will automatically restart. The protection mechanism is such that the unit can continue in this condition until the fault is cleared. Over-Temperature Protection These modules feature an over-temperature protection circuit to safeguard against thermal damage. The module will work on intermittent mode when the maximum device reference temperature is exceeded. When the TEL: (86) 755-86010808 S1 CNT1 -Vin Fig. 79 +Vout +Sense TRM Co1Co2 LOAD -Sense -Vout Typical application F1: Fuse. Use external fuse with a rating of 5A (fast blow type) for each unit. Cin: Recommended input capacitor. Use 47F/100V high frequency low ESR electrolytic type capacitor Co1: Recommended 1F/10V ceramic capacitor Co2: Recommended output capacitor Use 470F/10V high frequency low ESR electrolytic type capacitor. If Ta<-5C, use 220F tantalum capacitor parallel with a 470F/10V high frequency low ESR electrolytic capacitor. Note: The AVO75 modules cannot be used in parallel mode directly! Fusing The AVO75 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. www.emersonnetworkpower.com.cn 25/32 AVO75 Series DC/DC Converter TRN Standard safety agency regulations require input fusing. Recommended fuse ratings is 5A for the AVO75 Series. Note: the fuse is fast blow type. reverse polarity condition, which increases circuit efficiency and thermal performance. Input Reverse Voltage Protection Fig. 80 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 Fig. 80. In both cases the diode used is rated for 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 +Vin +Vin -Vin -Vin Reverse polarity protection circuit EMC For conditions where EMI is a concern, a different input filter can be used. Fig. 81 shows a filter designed to reduce EMI effects. AVO75 series can meet EN55022 CLASS A shown Fig. 81. +Vin +Vout CY3 * CY1 CY7 U CY9 Vin+ L1 CY5 Vout+ CX1 +Sense * CNT Cout1 Cout2 Trim Cin1 CY2 CX2 CY4 -Sense CY8 Vin- Vout- CY10 CY6 -Vin -Vout Fig. 81 EMI reduction filter Recommended values: Component Value/Rating Component Value/Rating CY1, CY2, CY5, CY6 4700PF/250VAC Cin1 47F/100V CX1 2.2/100V CX2 1F/100V CY7, CY8, CY9, CY10 1000PF/250VAC Cout1 470F/10V (low ESR capacitor) CY3, CY4 0.47 Cout2 1F/10V L1 1.8mH TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 26/32 AVO75 Series DC/DC Converter TRN 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 AVO75 series input-to-output isolation is a basic 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 input pin and one output 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. Note: To comply with the published safety standards, the following must be observed when using this built-in converter. 1. The built-in converter is intended for use as a component part of other equipment. When installing the power supply and marking input TEL: (86) 755-86010808 and output connections, the relevant safety standards e.g. UL 60950-1; IEC 60950-1/VDE 0805; EN60950-1; CAN/CSA-22.2NO. 60950-1-03 must be complied with, especially the requirements for creepage distances, clearances and distance through insulation between primary and earth or primary and secondary. 2. The output power taken from the built-in converter must not exceed the rating given on the built-in converter. 3. The built-in converter is not intended to be repaired by service personnel in case of failure or component defect (unit can be thrown away). 4. The maximum ambient temperature around the converter must not exceed 55C. 5. An external forced air cooling (CFM: 80.2, Speed: 1m/s, distance from unit: 20cm) shall be used for unit operate with full load and ambient up to 55C. 6. The built-in converter has no in-line fuse. For safety purpose, a fast acting UL listed fuse or UL recognized fuse rated 5A/250V needs to be connected to the input side as external protection. Thermal Consideration Thermal management is an important part of the system design. AVO75 series modules have ultra high efficiency at full load, and the module exhibit good performance during pro-longed exposure to high temperatures. However, to ensure proper and reliable operation, sufficient cooling of the power module and power derating is needed over the entire temperature range of the module. Considerations includes ambient temperature, airflow and module power derating. www.emersonnetworkpower.com.cn 27/32 AVO75 Series DC/DC Converter TRN 25 Output Current Io (A) Measuring the thermal reference point of the module as the method shown in Fig. 82 can verify the proper cooling. 20 2m/s 15 1.5m/s 1m/s 10 0.5m/s 5 0m/s 0 25 Thermistor Thermocouple location Fig. 83 Temperature measurement location Module Derating With 48V input, 55C ambient temperature, and 200LFM airflow, AVO75 series are rated for full power. For operation above ambient temperature of 55C, the output power must be derated as shown in Fig.83 to Fig.89. Meantime, airflow at least 200LFM over the converter must be provided to make the module working properly. It is recommended that the temperature of the thermal reference point be measured using a thermocouple. Temperature on the PCB at the thermocouple location shown in Fig. 82 should not exceed 125C in order to operate inside the derating curves as shown Fig. 83 to Fig 89. The use of output power derating curve is shown in the following example. Example What is the minimum airflow necessary for a AVO75-48S3V3 operating at VI = 48V, an output current of 20A, and a maximum ambient temperature of 55C? Solution Given: VI=48V, Io=20A, Ta=55C Determine airflow (v) (use Fig. 83 to Fig.89): v=1m/s. (200ft/min) TEL: (86) 755-86010808 AVO75-48S1V2 output power derating 25 Output Current Io (A) Fig. 82 85 Airflow direction from -Vin to +Vin; Vin=48V Thermocouple 20 2m/s 15 1.5m/s 10 1m/s 0.5m/s 5 0m/s 0 25 Fig. 84 40 55 70 TEMPERATURE, Ta ( ) 85 AVO75-48S1V5 output power derating Airflow direction from -Vin to +Vin; Vin=48V 25 Output Current Io (A) Notice: The thermocouple must not touch the pads of the thermistor 40 55 70 TEMPERATURE, Ta ( ) 20 2m/s 15 1.5m/s 10 1m/s 0.5m/s 5 0m/s 0 25 Fig. 85 40 55 70 TEMPERATURE, Ta ( ) 85 AVO75-48S1V8 output power derating Airflow direction from -Vin to +Vin; Vin=48V www.emersonnetworkpower.com.cn 28/32 AVO75 Series DC/DC Converter TRN 7 Output Current Io (A) Output Current Io (A) 25 20 2m/s 15 1.5m/s 10 1m/s 0.5m/s 5 0m/s 6 5 2m/s 4 1.5m/s 3 1m/s 2 0.5m/s 1 0m/s 0 0 25 Fig. 86 40 55 70 TEMPERATURE, Ta ( ) 85 AVO75-48S2V5 output power derating 25 Fig. 89 40 55 70 TEMPERATURE, Ta ( ) 85 AVO75-48S12 output power derating Airflow direction from -Vin to +Vin; Vin=48V Airflow direction from -Vin to +Vin; Vin=48V Output Current Io (A) 20 15 MTBF 2m/s 1.5m/s 10 1m/s 0.5m/s 5 0m/s 0 25 Fig. 87 40 55 70 TEMPERATURE, Ta ( ) 85 AVO75-48S3V3 output power derating Airflow direction from -Vin to +Vin; Vin=48V Output Current Io (A) 15 12 2m/s 9 The MTBF, calculated in accordance with Bellcore TR-NWT-000332, is 2,500,000 hours. Obtaining this MTBF in practice is entirely possible. If the board temperature is expected to exceed +25C, then we also advise an oriented for the best possible cooling in the air stream. Emerson Network Power can supply replacements for converters from other manufacturers, or offer custom solutions. Please contact the factory for details. 1.5m/s 1m/s 6 Mechanical Considerations 0.5m/s 3 0m/s 0 25 Fig. 88 40 55 70 TEMPERATURE, Ta ( ) 85 Installation AVO75-48S05 output power derating Airflow direction from -Vin to +Vin; Vin=48V TEL: (86) 755-86010808 Although AVO75 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. www.emersonnetworkpower.com.cn 29/32 AVO75 Series DC/DC Converter TRN Soldering AVO75 series converters are compatible with standard wave soldering techniques. When wave soldering, the converter pins should be preheated for 20 ~ 30 seconds at 110C, and wave soldered at 260C for less than 10 seconds. TEL: (86) 755-86010808 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. www.emersonnetworkpower.com.cn 30/32 AVO75 Series DC/DC Converter TRN Mechanical Chart (Top & pin side view) 57.9[2.28] 15.24[0.600] 22.9[0.90] 1 TOP VIEW 2 7.62[0.300] 4 5 6 7 3 8 15.24[0.600] 50.80[2.000] 8.5[0.34] 1.0 0.10 See Note 2 L 1.5 0.10 See note 3 2.0 0.1 Pin Length Option 8.5[0.34] Device Code Suffix TOLERANCES: XXmm=+/-0.5mm X.XXmm=+/-0.25mm L -4 4.8mm+/-0.5mm -6 3.8mm+/-0.5mm -8 2.8mm+/-0.25mm NONE 5.8mm+/-0.5mm Notes: 1, Un-dimensioned components are for visual reference only. 2, Pins 1~3, 5~7 are 1.0mm diameter with 2.0mm diameter standoff shoulders. 3. Pins 4, 8 are 1.5mm diameter with no standoff shoulders. Pin No. Function Pin No. Function 1 +Vin 5 +Sense 2 CNT 6 Trim 3 -Vin 7 -Sense 4 +Vo 8 -Vo TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 31/32 AVO75 Series DC/DC Converter TRN Ordering Information Input voltage (V) Output voltage (V) Output current (A) Ripple and noise (mV pp) AVO75-48S1V2 36~75 1.2 25 50 87 AVO75-48S1V5 36~75 1.5 25 55 88 AVO75-48S1V8 36~75 1.8 25 45 89 AVO75-48S2V5 36~75 2.5 25 50 90 AVO75-48S3V3 36~75 3.3 20 50 91 AVO75-48S05 36~75 5 15 55 92 AVO75-48S12 36~75 12 6.3 55 91 Model number Efficiency (%) Typ. Typ. Pb Hg Cd PBB PBDE 6 Cr SJ/T-11363-2006 x SJ/T-11363-2006 1 2 3 AVO75 TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 32/32 Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Emerson Network Power: AVO75-48S1V2P-4 AVO75-48S2V5-4 AVO75-48S2V5P-4 AVO75-48S12P-4 AVO75-48S05-6 AVO75-48S1V8-4 AVO75-48S05P-4 AVO75-48S1V8P-4 AVO75-48S05-4 AVO75-48S3V3-4 AVO75-48S1V2-4