? 2000 calirornia micro devices corp. all rights reserved. 12/5/2000 215 topaz street, milpitas, california 95035 tel: (408) 263-3214 fax: (408) 263-7846 www.calmicro.com california micro devices cmpwr300 1 500ma smartor tm dual regulator with v aux switch features ? 8-pin power soic package ? continuous 3.3v output from three inputs ? complete power management solution ?v cc , v sby regulator supplies 500ma output ? built-in hysteresis when selecting input supplies ? integrated switch has very low r ds(on) 0.12 w (typ.) ? large bypass capacitors on inputs not required applications ? pci adapter cards with wake-on-lan ? network interface cards (nics) ? multiple power systems ? systems with standby capabilities product description the cmpwr300 is a dual input regulator with v aux switch ca- pable of delivering 3.3v/500ma continuously. the output power is provided from three independent input voltage sources on a prioritized basis. power is always taken in priority using the fol- lowing order v cc , v sby , and v aux . when v cc (5v) or v sby is present, the device automatically en- ables the regulator and produces a stable 3.3v output at v out . when only v aux (3.3v) is present, the device provides a low impedance direct connection (0.12 w typ.) from v aux to v out . all the necessary control circuitry needed to provide a smooth and automatic transition between all three supplies has been incorporated. this allows both v cc and v sby to be dynamically switched without loss of output voltage. c0621199 cmpwr300? is a trademark of california micro devices corp. pin diagram typical application circuit simplified electrical schematic t s r a d n a n o i t a m r o f n i g n i r e d r o t r a p d e g a k c a pr e b m u n t r a p g n i r e d r o s n i pe l y t sg n i k r a m t r a p 8r e w o p c i o sa s 0 0 3 r w p m c when placing an order please specify desired shipping: tubes or tape & reel.
california micro devices ?2000 california micro devices corp. all rights reserved. 12/5/2000 215 topaz street, milpitas, california 95035 tel: (408) 263-3214 fax: (408) 263-7846 www.calmicro.com cmpwr300 2 s g n i t a r m u m i x a m e t u l o s b a r e t e m a r a pg n i t a rt i n u ) m b h ( n o i t c e t o r p d s e0 0 0 2v v c c v y b s e g a t l o v t u p n i5 . 0 - d n g , 0 . 6 +v v x u a e g a t l o v t u p n i5 . 0 - d n g , 0 . 4 +v e g n a r e r u t a r e p m e t e g a r o t s0 5 1 + o t 0 4 - t n e i b m a g n i t a r e p o0 7 + o t 0 o c n o i t c n u j g n i t a r e p o5 2 1 + o t 0 : n o i t a p i s s i d r e w o p 1 e t o n 0 . 1w s n o i t i d n o c g n i t a r e p o r e t e m a r a pe g n a rt i n u v , c c v y b s 5 2 . 0 0 . 5v v x u a 3 . 0 3 . 3v ) t n e i b m a ( e r u t a r e p m e t0 7 + o t 0 o c t n e r r u c d a o l0 0 5 o t 0a m c t x e % 0 1 0 1 m f s c i t s i r e t c a r a h c g n i t a r e p o l a c i r t c e l e ) e s i w r e h t o d e i f i c e p s s s e l n u s n o i t i d n o c g n i t a r e p o r e v o ( l o b m y sr e t e m a r a ps n o i t i d n o cn i mp y tx a mt i n u v t u o e g a t l o v t u p t u o r o t a l u g e ri > a m 0 0 5 d a o l a m 0 >5 3 1 . 30 3 . 35 6 4 . 3v i t u o t n e r r u c t u p t u o r o t a l u g e r 0 0 50 0 8a m v d a o l r n o i t a l u g e r d a o lv c c i , v 5 = d a o l a m 0 0 5 o t a m 0 5 =0 2v m v e n i l r n o i t a l u g e r e n i lv c c i , v 5 . 5 o t v 5 . 4 = d a o l a m 5 =2v m v l e s c c v c c e g a t l o v t c e l e s 0 5 . 40 6 . 4 v s e d c c v c c e g a t l o v t c e l e s e dv y b s >v s e d y b s r ov x u a t n e s e r p0 9 . 30 2 . 4v v l e s y b s v y b s e g a t l o v t c e l e sv c c , l e s c c i d a o l a m 0 =0 . 10 . 3 v n e h w ( c c ) t n e s e r p t o n s iv s e d c c v > c c v > t u o 5 1 . 05 2 . 0a m v t u o v > c c 1 0 . 02 0 . 0 i y b s v y b s t n e r r u c y l p p u sv y b s v > , l e s y b s i d a o l a m 0 =0 . 10 . 3 v n e h w ( c c ) t n e s e r p t o n s iv s e d y b s v > y b s v > t u o 5 1 . 05 2 . 0a m v t u o v > y b s 1 0 . 02 0 . 0 i x u a v x u a t n e r r u c y l p p u sv c c v r o y b s v > t u o 5 0 . 01 . 0a m v c c v d n a y b s ? 2000 calirornia micro devices corp. all rights reserved. 12/5/2000 215 topaz street, milpitas, california 95035 tel: (408) 263-3214 fax: (408) 263-7846 www.calmicro.com california micro devices cmpwr300 3 interface signals v cc is the primary power source which is given priority when present. if this connection is made within a few inches of the main input filter, a bypass capacitor may not be necessary. otherwise a bypass filter capacitor in the range of 1 m f to 10 m f will ensure adequate filtering. the voltage level on v cc is compared to an internal threshold voltage to determine which power source is to be selected. in order to prevent regulator dropout from occurring, the threshold has been programmed to ensure v cc is deselected prior to dropout, which prevents loss of output regulation when switching between v cc and v sby . typically the threshold is set to 4.2v. once v cc falls below this level, the output voltage is immediately derived from the auxiliary power source. to prevent chatter during this transition, the threshold has a built-in hysteresis of 300mv which results in only v cc being selected once the voltage level exceeds 4.50v (typically). v sby is the standby 5v supply power source, which is given priority when v cc is not present. the internal regulator will remain enabled until such time that v sby falls below the disable threshold level (4.2v typically). if the v sby connection is made within a few inches of the main input filter, a bypass capacitor may not be necessary. otherwise a bypass filter capacitor in the range of 1 m f to 10 m f will ensure adequate filtering. v aux is the auxiliary low voltage power source. this supply is only used when neither the v cc nor v sby is available. under these conditions an internal switch is enabled and provides a very low impedance connection directly between v out and v aux . v out is the output voltage. power is provided from the regulator or via the low impedance auxiliary switch. this output requires a capacitance of 10 m f to ensure regulator stability and minimize the peak output disturbance during power supply changeover. gnd provides the reference for all voltages. s l a n g i s e c a f r e t n i n i pl o b m y sn o i t p i r c s e d 1v y b s v n e h w r o t a l u g e r r o f t u p n i ) v 5 ( e g a t l o v y l p p u s y b d n a t s c c . v 2 . 4 w o l e b s l l a f 2v c c . r o t a l u g e r r o f t u p n i ) v 5 ( e g a t l o v y l p p u s y r a m i r p 3v t u o v r e h t i e n e h w r o t a l u g e r ) v 3 . 3 ( t u p t u o e g a t l o v r o t a l u g e r c c v r o y b s . t n e s e r p s i 4v x u a . h c t i w s e c n e d e p m i w o l r o f t u p n i ) v 3 . 3 ( e g a t l o v y l p p u s y r a i l i x u a 8 - 5d n g. s e g a t l o v l l a r o f e c n e r e f e r
california micro devices ?2000 california micro devices corp. all rights reserved. 12/5/2000 215 topaz street, milpitas, california 95035 tel: (408) 263-3214 fax: (408) 263-7846 www.calmicro.com cmpwr300 4 typical dc characteristics unless stated otherwise, all dc characteristics were measured at room temperature with a nominal v cc supply voltage of 5.0 volts and an output capacitance of 10 m f. fig 1.1. line regulation of the regulator is shown here. at maximum rated load conditions (500ma), a 100mv drop in regulation occurs when the line voltage falls below 3.8v. for light load conditions (100ma), regulation is maintained for line voltages as low as 3.5v. in normal operation the regulator is deselected at 4.2v, which ensures a regulation output drop of less than 100mv is maintained. fig 1.2. load regulation (pulse condition) performance is shown up to and beyond the rated load. a change in load from 10% to 100% of rated (50ma to 500ma) results in an output voltage change of about 20mv. this translates into an effective output impedance of less than 50m w . fig 1.3. v aux switch resistance is shown across a broad range of v aux supply level. from 2.7v and 3.6v, it only varies from about 130m w down to 110m w . fi g 1.2. load re g ulation (pulse condition) 3.24 3.26 3.28 3.30 3.32 3.34 3.36 0 200 400 600 800 load current [ma] vout [v] fi g 1.1. line re g ulation 3.05 3.10 3.15 3.20 3.25 3.30 3.35 3.0 3.5 4.0 4.5 5.0 vcc [v] vout [v] 100ma load 500ma load fig 1.3. vaux switch resistance vs. vaux 60 80 100 120 140 160 180 200 2.7 3 3.3 3.6 vaux [v] resistance [mohm]
? 2000 calirornia micro devices corp. all rights reserved. 12/5/2000 215 topaz street, milpitas, california 95035 tel: (408) 263-3214 fax: (408) 263-7846 www.calmicro.com california micro devices cmpwr300 5 fig 1.4. ground current is shown across the entire range of load conditions. the ground current has minimal variation across the range of load conditions and shows only a slight increase at maximum load due to the current limit protection circuitry. fig 1.5. v cc supply current of the device is shown across the entire v cc range for both v aux present (3.3v) and absent (0v). in the absence of v aux , the supply current remains fixed at approximately 1ma when v cc reaches the voltage level of about 2.5v. at this point the regulator is enabled and a supply current of 1.0ma is conducted. when v aux is present, the v cc supply current is less than 10ua until v cc exceeds v aux , at which point v cc then powers the controller (0.15ma). when v cc reaches v select , the regulator is enabled. fig 1.4. ground current 0.0 0.5 1.0 1.5 2.0 0 100 200 300 400 500 load current [ma] i gnd [ma] fig 1.5. vcc supply current (no load) 10 100 1000 10000 12345 vcc [v] i cc [a] va u x = 0 v vaux = 3.3v
california micro devices ?2000 california micro devices corp. all rights reserved. 12/5/2000 215 topaz street, milpitas, california 95035 tel: (408) 263-3214 fax: (408) 263-7846 www.calmicro.com cmpwr300 6 the transient characterization test setup shown below includes the effective source impedance of the v cc supply (r s ). this was measured to be approximately 0.2 w . it is recommended that this effective source impedance be no greater than 0.25 w to ensure precise switching is maintained during v cc selection and deselection. both the rise and fall times during v cc power-up/down sequencing were controlled to be around 10 millisecond duration. this is considered to represent worst case conditions for most application circuits. a maximum rated load current of 500ma was used during characterization, unless specified otherwise. during a selection or deselection transition the dc load current is switching from v aux to v cc and vice versa, or from v sby to v cc . in addition to the normal load current there may also be an in-rush current for charging/discharging the load capacitor. the total current pulse being applied to either v aux or v cc is equal to the sum of the dc load and the corresponding in-rush current. transient currents in excess of one amp can readily occur for brief intervals when either supply commences to power the load. the oscilloscope traces of v cc power-up/down show the full bandwidth response at the v cc and v out pins under full load (500ma) conditions. see application note ap-211 for more details. cold start and full power down (fig 2.1 to 2.6) cold start power up and power down from v cc , v sby and v aux . the output voltage follows the input very smoothly with no disturbance. as soon as the v cc or v sby input voltage reaches about 2v, v out starts rising. it reaches 3.3v when v cc or v sby equals 3.8v. v out remains valid until v cc or v sby drops below 3.8v. v cc power changeover (fig 2.7 to 2.12) power transitions between the main v cc and the standby or the auxiliary sources under 375ma load. the transition between v cc and v sby shows a small disturbance of 80mv on v out . transitions between v cc and v aux show a disturbance of about 120mv on v out . during power up condition, v cc experiences 100mv disturbance. this is due to the in-rush current during the power switching. the built-in hysteresis of 300mv ensures the regulator remains turned on throughout the transient. load and line transient response (fig 2.13 to 2.16) the load transient response shows a 5ma to 500ma step load with minimal disturbance on v out of 80mv. an initial transient overshoot of 80mv occurs and the output settles to its final voltage within a few microseconds. the dc voltage disturbance on the output is approximately 25mv, which demonstrates the regulator output impedance of 50mw. the line step response shows a small disturbance of 25mv on the output when v cc steps from 4.5v to 5.5v. when falling from 5.5v to 4.5v, the output is almost unchanged typical transient characteristics
? 2000 calirornia micro devices corp. all rights reserved. 12/5/2000 215 topaz street, milpitas, california 95035 tel: (408) 263-3214 fax: (408) 263-7846 www.calmicro.com california micro devices cmpwr300 7 typical transient characteristics - cold start and full power down fig 2.1 v cc cold start fig 2.2 v cc full power down fig 2.3 v sby cold start fig 2.4 v sby full power down fig 2.5 v aux cold start fig 2.6 v aux full power down
california micro devices ?2000 california micro devices corp. all rights reserved. 12/5/2000 215 topaz street, milpitas, california 95035 tel: (408) 263-3214 fax: (408) 263-7846 www.calmicro.com cmpwr300 8 typical transient characteristics - v cc power changeover fig 2.7 v cc power up (v sby = 5v) fig 2.8 v cc power down (v sby = 5v) fig 2.9 v cc power up (v aux = 3.3v) fig 2.10 v cc power down (v aux = 3.3v) fig 2.11 v cc power up (v aux = 3.1v) fig 2.12 v cc power down (v aux = 3.1v)
? 2000 calirornia micro devices corp. all rights reserved. 12/5/2000 215 topaz street, milpitas, california 95035 tel: (408) 263-3214 fax: (408) 263-7846 www.calmicro.com california micro devices cmpwr300 9 typical transient characteristics - load and line transient response fig 2.13 v cc load transient response rising fig 2.14 v cc load transient response falling fig 2.15 v cc load step response rising fig 2.16 v cc load step response falling
california micro devices ?2000 california micro devices corp. all rights reserved. 12/5/2000 215 topaz street, milpitas, california 95035 tel: (408) 263-3214 fax: (408) 263-7846 www.calmicro.com cmpwr300 10 thermal dissipation of junction heat consists primarily of two paths in series. the first path is the junction to the case ( q jc ) thermal resistance which is defined by the package style, and the second path is the case to ambient ( q ca ) thermal resistance, which is dependent on board layout. the overall junction to ambient ( q ja ) thermal resistance is equal to: q ja = q jc + q ca for a given package style and board layout, the operating junction temperature is a function of junction power dissipation p junc , and the ambient temperature, resulting in the following thermal equation: t junc = t amb + p junc ( q jc ) + p junc ( q ca ) = t amb + p junc ( q ja ) the CMPWR300SA is housed in a thermally enhanced package where the gnd pins (5 through 8) are integral to the leadframe (fused leadframe). when the device is mounted on a double sided printed circuit board with two square inches of copper allocated for ?heat spreading?, the resulting q ja is 50c/w. typical thermal characteristics based on a maximum power dissipation of 1.0w (2vx500ma) with an ambient of 70c the resulting junction temperature will be: t junc = t amb + p junc ( q ja ) = 70c + 1.0w (50c/w) = 70c + 50c = 120c all thermal characteristics of the CMPWR300SA were measured using a double sided board with two square inches of copper area connected to the gnd pins for ?heat spreading?. measurements showing performance up to junction temperature of 125c were performed under light load conditions (5ma). this allows the ambient temperature to be representative of the internal junction temperature. note: the use of multi-layer board construction with power planes will further enhance the thermal performance of the package. in the event of no copper area being dedicated for heat spreading, a multi-layer board construction will typically provide the CMPWR300SA with an overall q ja of 70c/w which allows up to 780mw to be safely dissipated. fig 3.1. output voltage vs. temperature. this shows the regulator v out performance up to the maximum rated junction temperature. the overall 125c variation in junction temperature causes an output voltage change of about 30mv.
? 2000 calirornia micro devices corp. all rights reserved. 12/5/2000 215 topaz street, milpitas, california 95035 tel: (408) 263-3214 fax: (408) 263-7846 www.calmicro.com california micro devices cmpwr300 11 fig 3.2. output voltage (rated) vs. temperature. this shows the regulator steady state performance when fully loaded (500ma) in an ambient temperature up to the rated maximum of 70c. the output variation at maximum load is below 10mv across the normal temperature operating. fig 3.3. thresholds vs. temperature. this shows the regulator select/deselect threshold variation up to the maximum rated junction temperature. the overall 125c change in junction temperature causes a 30mv variation in the select threshold voltage (regulator enable). the deselect threshold level varies about 30mv over the 125c change in junction temperature. this results in the built-in hysteresis have a minimal variation of 40mv over the entire operating junction temperature range. the hysteresis increases with temperature up to 240mv at 125c. fig 3.4. v aux switch resistance vs. temperature. this shows the v aux switch on resistance variation up to the maximum rated junction temperature. the overall 125c change in junction temperature causes a 80m w variation in the switch resistance. the switch resistance remains below 0.2 w , even at a junction temperature of 125c. typical thermal characteristics cont?d fig 3.3. thresholds vs. temperature 4.1 4.2 4.3 4.4 4.5 0 25 50 75 100 125 150 junction temperature [c] threshold [v] vselect vdeselect fig 3.4. vaux switch resistance vs. temperature 0 40 80 120 160 200 0255075100125 junction temperature [c] resistance [mohm] fi g 3.2. output volta g e (rated) vs. temperature 3.280 3.290 3.300 3.310 3.320 0 10203040506070 ambient temperature [ c] vout [v] 500ma load
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