a 15 watt tc dual series dc/dc converters 2401 stanwell drive concord, california 94520 ph: 925/687-4411 or 800/542-3355 fax: 925/687-3333 www.calex.com email: sales@calex.com 1 3/2001 features ! wide input voltage range ! efficiencies of 82% typical ! 1544 vdc isolation ! small 2.02" x 1.62" case ! overvoltage and overtemperature protection ! five year warranty description these 48 volt, dual output converters are designed to provide a wide range of power solutions. their extra wide input range of 20 to 72 vdc covers both the common american and european telecom standards plus 24 volt industrial control applications. for flexibility, the output voltage can be adjusted with a trim pin to compensate for voltage drops or to achieve non- standard voltages. a remote on/off function maximizes battery life. the tc dual series continues the calex tradition of reliable design by including transient overvoltage suppressor diode protection. overcurrent and overtemperature protection circuits are also standard. all calex products are backed by a five year warranty. 15 watt tc dual series block diagram t r a h c n o i t c e l e s l e d o m e g n a r t u p n i c d v t u p t u o c d v t u p t u o a m n i mx a m c t 5 2 6 . 2 1 d 8 4 0 2* 2 72 1 5 2 6 c t 0 0 5 . 5 1 d 8 4 0 2* 2 75 1 0 0 5 * ul recognition only applies up to 60 vdc
a 15 watt tc dual series dc/dc converters 2401 stanwell drive concord, california 94520 ph: 925/687-4411 or 800/542-3355 fax: 925/687-3333 www.calex.com email: sales@calex.com 2 3/2001 * s r e t e m a r a p t u p t u o l e d o mc t 5 2 6 . 2 1 d 8 4c t 0 0 5 . 5 1 d 8 4s t i n u e g a t l o v t u p t u o2 1 5 1 c d v e g n a r d a o l d e t a r n i m x a m 0 5 2 6 0 0 0 5 a m e g n a r e g a t l o v n i m p y t x a m 0 0 9 . 1 1 0 0 0 . 2 1 0 0 1 . 2 1 0 0 9 . 4 1 0 0 0 . 5 1 0 0 1 . 5 1 c d v ) 4 ( n o i t a l u g e r d a o l d a o l l l u f % 0 0 1 - % 0 p y t x a m 5 1 . 0 4 . 0 % ) 5 ( n o i t a l u g e r s s o r c d a o l % 0 0 1 - % 5 2 p y t x a m 5 . 1 0 . 3 % n o i t a l u g e r e n i l c d v x a m - n i m = n i v p y t x a m 4 0 . 0 2 . 0 % ) 6 ( y t i l i b a t s m r e t t r o h sp y t2 0 . 0 b d ) 1 ( w b z h m 0 2 - 0 , e s i o n r o t i c a p a c l a n r e t x e f 1 . 0 h t i w r o t i c a p a c l a n r e t x e o n h t i w p y t p y t 0 3 0 7 p - p v m p - p v m t n e i c i f f e o c e r u t a r e p m e t p y t x a m 0 5 0 5 1 c / m p p ) 0 1 ( p m a l c e g a t l o v r e v op y t8 1c d v o t n o i t c e t o r p t i u c r i c t r o h s s t u p t u o l l a r o f n o m m o c l a m r e h t d n a g n i t i m i l t n e r r u c h t i w n o i t c e t o r p s u o u n i t n o c s e u q i n h c e t d a o l r e v o notes * all parameters measured at 25c, nominal input voltage and full rated load unless otherwise noted. refer to the calex application notes for the definition of terms, measurement circuits and other information. (1) noise is measured per calex application notes. measurement bandwidth is 0-20 mhz. (2) an input capacitor must be used for proper operation of the converter. see the application note on sizing the input capacitor. (3) see the typical application note. also refer to calex application notes on fuse sizing. (4) load regulation for the outputs is specified as the voltage change when both outputs are changed from maximum to minimum at the same time. (5) cross regulation is defined as the change in one output when the other output is changed from full load to 25% of full load. the converter can be run at no load on either or both outputs with no damage. (6) short term stability is specified after a 60 minute warmup at full load, constant line and recording the drift over a 24 hour period. (7) the transient response is specified as the time required to settle from a 50 to 75 % step load change (rise time of step = 2 s) to a 1% error band. (8) dynamic response is the peak overshoot during a transient as defined in note 7 above. (9) the input ripple rejection is specified for dc to 120 hz ripple with a modulation amplitude of 1% of vin. (10) for module protection only, see also note 3. (11) the logic on/off pin is open collector ttl, cmos, and relay compatible. the input to this pin is referenced to pin 2, -input and is protected to +100 vdc. (12) case is tied to pin 1, + input. (13) the case thermal impedance is specified as the case temperature rise over ambient per package watt dissipated. (14) specifications subject to change without notice. * s r e t e m a r a p t u p n i l e d o mc t 5 2 6 . 2 1 d 8 4c t 0 0 5 . 5 1 d 8 4s t i n u e g n a r e g a t l o v n i m p y t x a m 0 . 0 2 0 . 8 4 * 0 . 2 7 c d v ) 2 ( ) 1 ( e l p p i r d e t c e l f e rp y t0 6 6p - p a m d a o l l l u f t n e r r u c t u p n i d a o l o n p y t p y t 4 8 3 5 1 8 3 5 a m y c n e i c i f f ep y t1 82 8% y c n e u q e r f g n i h c t i w sp y t0 2 1z h k s m 0 0 1 e g a t l o v r e v o t u p n i m u m i x a mx a m5 8c d v r o r r e t u p t u o % 1 , e m i t n o - n r u tp y t2 s m e s u f d e d n e m m o c e rp y t) 3 (s p m a * ul recognition only applies up to 60 vdc
a 15 watt tc dual series dc/dc converters 2401 stanwell drive concord, california 94520 ph: 925/687-4411 or 800/542-3355 fax: 925/687-3333 www.calex.com email: sales@calex.com 3 3/2001 n i pn o i t c n u f 1t u p n i + 2t u p n i - 4f f o / n o 5t u p t u o + 6n m c t u p t u o 7t u p t u o - 8m i r t bottom view side view mechanical tolerances unless otherwise noted: x.xx dimensions: 0.010 inches x.xxx dimensions: 0.005 inches figure 1. typical application sizing the input capacitor for maximum reliability the 15 watt tc dual series dc/dc converter must use a capacitor of sufficient ripple handling capability connected across the input pins. the probable result of undersizing (over stressing) this capacitor is increased self heating and shortening of the capacitors and hence your system ? s life. oversizing the capacitor can have a negative effect on your product ? s cost and size, although this kind of overdesign does not result in shorter life of any components. there is no one optimum value for this capacitor. the size and capacity are dependent on the following factors: 1) expected ambient temperature and your temperature derating guidelines. 2) your ripple current derating guidelines. 3) the maximum load expected on the converter. 4) the minimum input voltage expected on the converter. 5) the statistical probability that your system will spend a significant amount of time at any worst case extreme. factors 1 and 2 are determined by your system design guidelines. these can range from 50% to 100% of the manufacturer ? s rated maximum, although a usual derating factor is 70% of manufacturer ? s maximum limit. 70% derating means that if the capacitor manufacturer says the capacitor can do 1a rms and 100 vdc you would not use the part over 15 watt tc dual typical application an input capacitor is required for proper operation (see figure 1). the trim and on/off pins can be safely left floating if they are not used. the input fuse should not be omitted. the fuse prevents unlimited current from flowing in the case of a catastrophic system failure. an input capacitor is required for proper operation. see note text. * s n o i t a c i f i c e p s l a r e n e g s l e d o m l l as t i n u ) 1 1 ( n o i t c n u f f f o / n o l e v e l c i g o l n o g n i t a o l f n i p e v a e l r o n i m0 . 8c d v l e v e l c i g o l f f ox a m0 . 2c d v e c n a t s i s e r t u p n ip y t0 0 1s m h o k t n e r r u c e l d i r e t r e v n o c w o l n i p f f o / n o p y t2 a m ) 2 1 ( n o i t a l o s i e g a t l o v n w o d k a e r b e g a k a e l a 0 1 t u p t u o - t u p n i n i m4 4 5 1c d v t u p t u o o t t u p n i e c n a t i c a p a c p y t0 5 4f p n o i t c n u f m i r t t u p t u o e c n a t s i s e r t u p n ip y t0 4s m h o k e g n a r g n i m m a r g o r pn i m4 3 - , 5 +% l a t n e m n o r i v n e e g n a r g n i t a r e p o e s a c g n i t a r e d o n n i m x a m 0 4 - 0 0 1 c e g n a r e g a r o t s n i m x a m 5 5 - 5 0 1 c ) 3 1 ( e c n a d e p m i l a m r e h tp y t0 1t t a w / c n w o d t u h s l a m r e h t e r u t a r e p m e t e s a c p y t5 0 1c l a r e n e g t h g i e w t i n up y t4 2 . 2z o t i k g n i t n u o m s i s s a h c8 s m s l a v o r p p a y c n e g ae t o n e e s , 0 5 9 1 l u note: on nominal 48vin models ul recognition only applies up to 60 vdc
a 15 watt tc dual series dc/dc converters 2401 stanwell drive concord, california 94520 ph: 925/687-4411 or 800/542-3355 fax: 925/687-3333 www.calex.com email: sales@calex.com 4 3/2001 maximum) because these usually have the highest ripple current capability per unit volume. be careful to compare apples to apples. some manufacturers specify their capacitors at 85 c and others specify at 105 c. the manufacturers give temperature derating guidelines, so all capacitors should be normalized to your maximum ambient (plus 5 to account for self heating) before making a selection. since the 15 watt tc dual series operates at 120 khz the frequency usually does not have to be derated since most modern low esr capacitors are rated at 100 khz. one note: the temperature derating multipliers are set up on the basis of the same life as would be expected at 105 c. the life of a capacitor operating at a significantly lower temperature will not be greater if the ripple current in the part is increased over the 105 c rating. this means that a capacitor rated for 1a rms current at 105 c and 2a rms at 50 c will have the same life if used at either point, while the same capacitor used at 1a rms and 50 c will have a longer life. suggested capacitor sources suitable capacitors can be found from the following sources: united chemi-con sxe, rxc, rz and rza series suggested part: sxe100vb221m12.5x35ll 220 f, 100v, 105 c rated esr = 0.087 ohms, allowable ripple = 1.04 a nichicon pr and pf suggested part: upr100102mphrh 1000f, 100v, 105 c rated esr = 0.047 ohms, allowable ripple = 1.32 a panasonic hfe series suggested part: ecea2afe221l 220f, 100v, 105 c rated esr = 0.089 ohms, allowable ripple = 1.04 a the suggested capacitors will work worst case for any line and load condition. they may be oversized for your application, however. see the discussion above on capacitor sizing. remote on/off circuit operation the remote on/off pin is best applied as follows: ! to turn the unit off, the on/off pin should be tied to the - input pin. this is best done by an open collector arrangement or contact closure. ! to turn the unit on, let the on/off pin float. ! if the remote on/off pin is not used, it may be safely left floating. there is a 100k internal pullup resistor inside the unit to +9 volts dc. other applications of the on/off function can be found in the calex application note: ? understanding the remote on/off function. ? 700 ma rms and 70 vdc. surge voltage rating should also be evaluated against any expected voltage surges when selecting a capacitor working voltage. factors 3 and 4 determine the worst case ripple current. the reflected ripple current increases with output load and it increases as the input voltage decreases. so if you are running with a solid 48 vdc input and at 50% load your capacitors required ripple current rating would decrease by nearly 2.7:1 under what would be required for operation at 20 vdc with full load (see the ? input ripple ? curve). factor 5 is not easy to quantify. at calex we can make no assumptions about a customer ? s system so we design for continuous operation at worst case extremes. however, you can make educated assumptions about your system ? s usage. it might not be strategically or economically sound to design a system to survive in a worst case environment if you know that no systems are likely to be in such an environment long term. example of capacitor sizing given the following conditions select the minimum size capacitor needed to give reliable performance: converter .............................................. 48d12.625tc minimum input voltage ......................... 40 vdc maximum input voltage ........................ 52 vdc maximum load ..................................... 470 ma maximum ambient temperature .......... 40 c your capacitor voltage derating guideline ..... 70% of maximum specification your capacitor current derating guideline ..... 70% of maximum specification solution looking at the 15 watt tc dual series ? reflected ripple vs. line input ? curve at 40 vdc input and 470 ma output (75% of rated load) the reflected input ripple can be read as 590 ma rms. from the derating guidelines the capacitor ? s rated voltage and ripple current can be found. capacitor voltage rating is calculated as: v = x maximum expected input v = (1/0.7) x 52 vdc = 74 volts or greater the next larger standard value is 80 vdc. capacitor ripple current rating is calculated as: i = x reflected ripple i = (1/0.7) x 590 ma = 843 ma rms or greater at 45 c (40 c ambient + 5 c for self heating). a capacitor selection can now be made. look only at controlled low esr types (where the esr is specified as a 1 voltage derating factor 1 current derating factor
a 15 watt tc dual series dc/dc converters 2401 stanwell drive concord, california 94520 ph: 925/687-4411 or 800/542-3355 fax: 925/687-3333 www.calex.com email: sales@calex.com 5 3/2001 figure 2. output trim methods proper application of the trim pin the trim pin is used to adjust the output voltage slightly to compensate for voltage drops in the system ? s wiring. figure 2 shows the proper application of the trim pin. either a 10 k trimpot or a fixed resistor may be used. the tc series can be adjusted easily for other non- standard output voltages. to get 8 or 9 volts for rf applications a 12 volt output converter can be used. the output power must be limited to 15 watts when trimming the output up (the output current must be reduced to keep a constant power output). when trimming the output down, the output current must be kept at or below the maximum current listed for that model. temperature derating guidelines care must be taken in the application of all power devices. be sure to account for the self heating in your instrument due to the power converter and the loads. for minimum temperature gradient, the hottest components should be mounted at the bottom of your system (bottom of a vertical pcb) and the coolest components at the top of the system. this will help to even out the temperature of the entire system and prevent temperature gradients. the 15 watt tc dual series has a thermal impedance of 10 c per package watt dissipated. in normal operation the 15 watt tc dual series can be expected to run at 81 % efficiency at 48 vdc and full load. this means that the 15 watt tc dual series is dissipating nearly 3.5 watts internally at full load. this translates to a package temperature rise of 35 c (10 c/ watt x 3.5 watts dissipated). the maximum rated case temperature for the 15 watt tc series is 100 c. this means that in the absence of other heat sources (including the load that the tc is powering) and with at least 3 inches of clearance the 15 watt tc dual series could be expected to operate at an ambient of 65 c. additional heat sinking or cooling air flow can extend the ambient temperature of operation significantly. in the event of system cooling blockage or failure, the thermal shut-off of the 15 watt tc dual series will prevent any catastrophic power converter failure. when the ambient temperature cools below the thermal limit temperature the unit will restart.
a 15 watt tc dual series dc/dc converters 2401 stanwell drive concord, california 94520 ph: 925/687-4411 or 800/542-3355 fax: 925/687-3333 www.calex.com email: sales@calex.com 6 3/2001 typical performance (tc=25 c, vin=nom vdc, rated load). 20 24 28 32 36 40 44 48 52 56 60 64 68 72 line input (volts) 75 80 85 90 efficiency (%) efficiency vs. line input (12v output) 100% full load 50% full load 10 100 1000 10000 100000 1000000 frequency (hz) .01 .1 1 10 output impedance (ohms) output impedance vs. frequency 20 24 28 32 36 40 44 48 52 56 60 64 68 72 line input (volts) 0.0 0.2 0.4 0.6 0.8 1.0 reflected rms ripple (amps) input ripple vs. line input (12v output) 100% full load 50% full load 75% full load -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 case temperature (deg c) -0.35 -0.30 -0.25 -0.20 -0.15 -0.10 -0.05 -0.00 0.05 normalized output (%) output voltage vs. case temperature 0 8 16 24 32 40 48 56 64 72 line input (volts) 0.0 0.3 0.6 0.9 1.2 input current (amps) input current vs. line input (12v output) 100% full load 50% full load 0 50 100 150 200 250 300 350 400 output load (%) 0 20 40 60 80 100 120 output voltage (%) output voltage vs. output load (12v output) 0 102030405060708090100 load (%) 60 70 80 90 efficiency (%) efficiency vs. load (12v output) line = 20vdc line = 48vdc line= 72vdc -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 ambient temperature (deg c) 0 20 40 60 80 100 120 output power (%) derating infinite heat sink no heat sink safe operating area
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