voute voutd voutc voutb vouta nc gnd2 gnd2 gnd2 fb typical applications 4707 dey road liverpool, n.y. 13088 (315) 701-6751 mil-prf-38534 certified 5910rh m.s.kennedy corp. features: satellite system power supplies switching power supply post regulators constant voltage/current regulators microprocessor power supplies rad tolerant ultra low dropout adjustable positive linear regulator equivalent schematic typical applications description: the msk 5910rh is a rad tolerant adjustable linear regulator capable of delivering 5.0 amps of output current. the typical dropout is only 0.11 volts at 1 amp. an external shutdown/reset function is ideal for power supply sequencing. this device also has latching overload protection that requires no external current sense resistor. the msk 5910rh is radiation tolerant and specifically designed for many space/satellite applications. the device is packaged in a hermetically sealed 20 pin flatpack that can be lead formed for surface mount applications. pin-out information vina vinb vinc vind vine vbias gnd1 gnd1 latch shutdown total dose tested to 300k rad ultra low dropout for reduced power consumption external shutdown/reset function latching overload protection adjustable output using two external resistors output current limit surface mount package available with lead forming low input voltage for maximum efficiency up to 5a output current available to dscc smd #5962-05220 1 2 3 4 5 6 7 8 9 10 rev. i 3/06 1 20 19 18 17 16 15 14 13 12 11
input voltage range input bias voltage feedback voltage feedback pin current quiescent current bias current line regulation load regulation dropout voltage minimum output current output voltage range output current limit shutdown threshold shutdown hysteresis ripple rejection phase margin gain margin equivalent noise voltage thermal resistance storage temperature range lead temperature range (10 seconds) power dissipation junction temperature absolute maximum ratings 10.0v 10.0v 5a -55c to +125c -40c to +85c bias supply voltage supply voltage output current case operating temperature range msk5910k/h/e rh MSK5910RH -65c to +150c 300c see soa curve 150c 1 2 3 4 5 6 7 8 9 t st t ld p d t c +v bias +v in i out t c unless otherwise specified, v bias =v in =5.0v, r1=1.62k, v shutdown =0v and i out =10ma. i out is subtracted from i q measurement. guaranteed by design but not tested. typical parameters are representative of actual device performance but are for reference o nly. industrial grade and "e" suffix devices shall be tested to subgroups 1 and 4 unless otherwise requested. military grade devices ("h" suffix) shall be 100% tested to subgroups 1,2,3 and 4. subgroup 5 and 6 testing available upon request. subgroup 1,4 t c =+25c subgroup 2,5 t c =+125c subgroup 3,6 t a =-55c output current limit is tested with a low duty cycle pulse to minimize junction heating and is dependent on the values of v in , v out and case temperature. see typical performance curves. contact factory for post radiation limits. continuous operation at or above absolute maximum ratings may adversely effect the device performance and/or life cycle. notes: group a subgroup 1,2,3 1,2,3 1 2,3 1,2,3 1,2,3 1,2,3 1 2,3 1 2,3 1 2,3 1 2,3 - 1 2,3 1 2,3 1 2,3 4 5,6 4,5,6 4,5,6 4,5,6 - 10ma i out 1.0a v bias v in i out = 1.0a r1=187 ? v fb =1.265v 10ma i out 1.0a i in +i bias, v bias =v in =7.5v not including i out v bias =7.5v i out =10ma 2.8v v in 7.5v r1=187 ? 10ma i out 1.0a r1=976 delta fb=1% i out =1.0a 2.8v v in 7.5v r1=187 ? v in =7.5v v in =2.5v v out =1.5v v out 0.2v (off) v out =nominal (on) difference between voltage threshold of v sdi (on) and v sdi (off) f=1khz to 10khz 10ma i out 1.0a 1.0v=v in -v out i out =450ma i out =45oma referred to feedback pin junction to case @ 125c output device typ. - 5.0 1.265 - - 14 2 0.01 - 0.06 - 0.11 0.14 8 9 - 3.6 - 1.3 1.3 0.02 0.03 - - 80 30 - 7.3 test conditions max. 7.5 7.5 1.305 1.305 5.0 20 4 0.50 0.50 0.80 0.80 0.40 0.40 10 10 7.0 4.0 - 1.6 1.6 0.2 0.2 - - - - 50 8.4 min. 2.0 2.8 1.225 1.225 0 - - - - - - - - - - 1.5 3.2 3.0 1.0 1.0 - - 20 20 30 10 - - min. 2.0 2.8 1.202 - 0 - - - - - - - - - - 1.5 3.2 - 1.0 - - - 20 - 30 10 - - max. 7.5 7.5 1.328 - 5.0 20 4 0.60 - 1.0 - 0.45 - 10 - 7.0 4.0 - 1.6 - 0.2 - - - - - 50 9.0 typ. - 5.0 1.265 - - 14 2 0.01 - 0.06 - 0.11 - 8 - - 3.6 - 1.3 - 0.02 - - - 80 30 - 7.3 v v v v a ma ma %v out %v out %v out %v out v v ma ma v a a v v v v db db degrees db v rms c/w msk5910k/h/e msk5910 parameter electrical specifications 2 rev. i 3/06 units 1 8 2 2 2 7 2 2 2 2 2 2 8 2 7 9
application notes vin a,b,c,d,e - these pins provide the input power connection to the msk 5910rh. this is the supply that will be regulated to the output. all five pins must be connected for proper opera- tion. vbias - this pin provides power to all internal circuitry including bias, start-up, thermal limit and overcurrent latch. vbias volt- age range is 2.8v to 7.5v. vbias should be kept greater than or equal to vin. gnd1 - internally connected to input ground, these pins should be connected externally by the user to the circuit ground and the gnd2 pins. latch - the msk 5910rh has a timed latch-off circuit which provides overcurrent protection. an overcurrent or output short condition will saturate the internal drive transistor. the time-out latch will then be triggered and turn off the regulator. the time- out period is determined by an external capacitor connected between the latch and gnd pins. once the overcurrent condi- tion is removed, the latch can be reset by pulling the shut- down pin high, grounding the latch pin or cycling power off, then on. holding the latch pin low disables current limiting. un- der normal conditions, the voltage at the latch pin is zero. when the device is latched off, the voltage at the latch pin will be 1.6v at 25c. shutdown - there are two functions to the shutdown pin. it may be used to disable the output voltage or to reset the latch pin. to activate the shutdown/reset functions the user must apply a voltage greater than 1.3v to the shutdown pin. the output voltage will turn on when the shutdown pin is pulled below the threshold voltage. if the shutdown pin is not used, it should be connected to ground. fb - the fb pin is the inverting input of the internal error ampli- fier. the non-inverting input is connected to an internal 1.265v reference. this error amplifier controls the drive to the output transistor to force the fb pin to 1.265v. an external resistor divider is connected to the output, fb pin and ground to set the output voltage. gnd2 - internally connected to output ground, these pins should be connected externally by the user to the circuit ground and the gnd1 pins. vout a,b,c,d,e - these are the output pins for the device. all five pins must be connected for proper operation. typically, large bulk capacitance is required at the output of a linear regulator to maintain good load transient response. how- ever, with the msk 5910rh this is not the case. a 47f surface mount tantalum capacitor in parallel with a 0.1f ceramic ca- pacitor from the output to ground should suffice under most conditions. if the user finds that tighter voltage regulation is needed during output transients, more capacitance may be added. if more capacitance is added to the output, the bandwidth may suffer. as previously mentioned, the latch pin provides over cur- rent/output short circuit protection with a timed latch-off circuit. the latch off time out is determined with an external capacitor connected from the latch pin to ground. the time-out period is equal to the time it takes to charge this external capacitor from 0v to 1.6v. the latch charging current is provided by an internal current source. this current is a function of bias voltage and temperature (see latch charging current curve). for instance, at 25c, the latch charging current is 7.2a at vbias=3v and 8a at vbias=7v. in the lat ch-off mode, some additional current will be drawn from the bias supply. this additional latching current is also a function of bias voltage and temperature (see latching current curve). the msk 5910rh current limit function is directly affected by the input and output voltages. custom current limit is available; contact the factory for more information. 3 rev. i 3/06 power supply bypassing to maximize transient response and minimize power supply transients it is recommended that a 33f minimum tantalum capacitor is connected between vin and ground. a 0.1f ce- ramic capacitor should also be used for high frequency bypass- ing. start up options the msk 5910rh starts up and begins regulating immediately when vbias and vin are applied simultaneously. applying vbias before vin starts the msk 5910rh up in a disabled or latched state. when starting in a latched state the device output can be enabled either by pulling the latch pin low to drain the latch ca- pacitor or pulsing the shutdown pin high. the shutdown pulse duration is partially dependent upon the size of the latch capacitor and should be characterized for each application; 30us is typically adequate for a 1uf latch capacitor at 25c. a momentary high pulse on the shutdown pin can be achieved using the rc circuit below if vin rises rapidly. the resistor and capacitor must be selected based on the required pulse duration, the rise character- istic of vin and the shutdown pin threshold (see shutdown pin threshold and current curves). the shutdown pin can be held high and pulled low after vin comes up or the latch pin held low and released after vin comes up to ensure automatic startup when applying vbias before vin. ei- ther of the basic circuits below can be adapted to a variety of applications for automatic start up when vbias rises before vin. pin functions output capacitor selection overcurrent latch-off/latch pin capacitor selection
application notes cont. 4 rev. i 3/06 heat sink selection to select a heat sink for the msk 5910rh, the follow- ing formula for convective heat flow may be used. governing equation: t j = p d x (r jc + r cs + r sa ) + t a where t j = junction temperature p d = total power dissipation r jc = junction to case thermal resistance r cs = case to heat sink thermal resistance r sa = heat sink to ambient thermal resistance t a = ambient temperature power dissipation=(v in -v out ) x i out next, the user must select a maximum junction tem- perature. the absolute maximum allowable junction tem- perature is 150c. the equation may now be rearranged to solve for the required heat sink to ambient thermal resistance (r sa ). example: an msk 5910rh is connected for v in =+5v and v out =+3.3v. i out is a continuous 1a dc level. the ambient temperature is +25c. the maximum desired junction temperature is +125c. r jc =8.5c/w and r cs =0.15c/w for most thermal greases power dissipation=(5v-3.3v) x (1a) =1.7watts solve for r sa: 125c - 25c 1.7w = 50.2c/w in this example, a heat sink with a thermal resistance of no more than 50c/w must be used to maintain a junction temperature of no more than 125c. v out =1.265(1+r1/r2) output voltage selection as noted in the above typical applications circuit, the formula for output voltage selection is a good starting point for this output voltage selection is to set r2=1k. by rearranging the formula it is simple to calculate the final r1 value. table 1 below lists some of the most probable resistor combinations based on industry standard usage. table 1 r1 r2 1+ v out =1.265 v out 1.265 -1 r1=r2 1.5 1.8 2.0 2.5 2.8 3.3 4.0 5.0 r2 ( ? ? ? ? ? ) 1k 1k 1k 1k 1k 1k 1k 1k r1 (nearest 1%) ( ? ? ? ? ? ) 187 422 576 976 1.21k 1.62k 2.15k 2.94k r sa = -8.5c/w - 0.15c/w output voltage (v) typical applications circuit thermal limiting the msk 5910rh control circuitry has a thermal shut- down temperature of approximately 150c. this ther- mal shutdown can be used as a protection feature, but for continuous operation, the junction temperature of the pass transistor must be maintained below 150c. proper heat sink selection is essential to maintain these condi- tions.
typical performance curves rev. i 3/06 5
radiation performance curves rev. i 3/06 6
industrial extended reliability 7 rev. i 3/06 note: all dimensions are 0.010 inches unless otherwise labeled. esd triangle indicates pin 1. ordering information MSK5910RH msk5910erh msk5910hrh screening level mil-prf-38534 class h mil-prf-38534 class k dscc smd 5962-05220 msk5910krh weight=3.5 grams typical mechanical specifications leads straight part number note: see dscc smd 5962-05220 for dscc part number options.
all dimensions are 0.010 inches unless otherwise labeled. esd triangle indicates pin 1. rev. i 3/06 the information contained herein is believed to be accurate at the time of printing. msk reserves the right to make changes to its products or specifications without notice, however, and assumes no liability for the use of its products. please visit our website for the most recent revision of this datasheet. contact msk for mil-prf-38534 class h, class k and appendix g (radiation) status. m.s. kennedy corp. 4707 dey road, liverpool, new york 13088 phone (315) 701-6751 fax (315) 701-6752 www.mskennedy.com ordering information 8 weight=3.3 grams typical mechanical specifications continued industrial extended reliability MSK5910RHg msk5910erhg msk5910hrhg screening level mil-prf-38534 class h mil-prf-38534 class k dscc smd 5962-05220 msk5910krhg leads gull wing part number note: see dscc smd 5962-05220 for dscc part number options.
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