half and full bridge motor drives audio power amplifiers headphones cellular phones, pcmcia, pda ideal for single supply systems 5v - peripheral 12v - automotive 28v - avionic 4707 dey road liverpool, n.y. 13088 (315) 701-6751 features: iso-9001 certified by dscc m.s.kennedy corp. extremely compact surface mount package low cost dual high power amplifier wide supply voltage range: 5v to 40v high output current: 2a high efficiency: |vs-2.2v| at 2a internal current limit wide common mode range (includes negative supply voltage) low distortion equivalent schematic the msk 173 is a high power dual operational amplifier. each amplifier is capable of delivering two amps of current to the load. the msk 173 is an excellent low cost alternative for bridge mode configurations since both amplifiers are packaged together and will track thermally. the wide common mode range includes the negative rail, facilitating single supply applications. it is possible to have a "ground based" input driving a single supply amplifier with ground acting as the second or "bottom" supply of the amplifier. the output stage is current limit protected to approximately 4.0 amps. the msk 173 is packaged in an extremely space efficient 10 pin power soic package. the msk 173-1 is packaged in a 10 pin flatpack. consult the factory for other packaging options if desired. description: 1 all power pins must be electrically connected for proper operation. pin-out information 1 2 3 4 5 -input 1 +input 1 -vcc +input 2 -input 2 +vcc output 1 +vcc output 2 +vcc rev. h 8/00 the heat sink of the package and the lid are electrically connected to -vcc. the heat sink tab must be connected to the system -vcc. heat sink 10 9 8 7 6 typical applications 173/173-1 high power dual operational amplifier MSK173 MSK173-1 mil-prf-38534
1 2 3 4 5 6 static supply voltage range input offset voltage drift power supply rejection common mode rejection total noise output output voltage swing output current peak current limit power bandwidth crosstalk capacitive load transfer characteristics slew rate open loop voltage gain (split supply) total; v in =0v v in =0v v cm =0v full temp. d v cc =15v v cm =10vdc r l =500 w a v =1 c l =1500pf v out =max v out =28v pp i out =1a f=1khz a v =+1v/v f=10hz r l =500 w -65c to +150c 300c -55c to+125c -40c to +85c 3.0c/w 12.0c/w storage temperature lead temperature case operating temperature (MSK173b,173b-1 ) (MSK173,173-1) thermal resistance (dc) junction to case msk 173 msk 173-1 total supply voltage output current (within s.o.a.) input voltage (differential) input voltage (common mode) junction temperature 40v 3a pk v cc +v cc , -v cc -0.5v 150c absolute maximum ratings t st t ld t c r th v cc i out v ind v in t j unless otherwise noted v cc =15vdc. devices shall be capable of meeting the parameter, but need not be tested. typical parameters are for reference only. industrial grade devices shall be tested to subgroups 1 and 4 unless otherwise requested. military grade devices ('b' suffix) shall be 100% tested to subgroups 1,2,3 and 4. consult factory for availability of militar y grade devices. 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 group a subgroup - 1 2 3 1 2, 3 - - - - - - 4 - - - - - 4 - typ. 15 35 50 30 0.5 2.0 20 35 75 80 85 0.1 14.2 3.0 4.0 13.6 68 0.22 1.2 100 min. 2.5 - - - - - - - - 60 60 - 14 2.0 - - 60 - 0.5 80 min. 2.5 - - - - - - - - 60 60 - 14 2.0 - - - - 0.5 80 max. 20 60 - - 15 - - 1000 - - - 1.0 - - - - - - - - typ. 15 35 - - 2 - 20 35 75 80 85 0.1 14.2 3.0 4.0 13.6 68 0.22 1.2 100 units v ma ma ma mv mv v/c na na db db mv v a a khz db f v/s db parameter max. 20 50 75 50 10 15 50 500 1000 - - 1.0 - - - - - - - - test conditions electrical specifications notes: quiescent current v in =0v offset voltage input bias current 2 4 4 MSK173 MSK173-1 2 2 2 2 2 2 2 2 2 1 2 MSK173b MSK173b-1 rev. h 8/00
application notes safe operating area (soa) amplifier stability since both output transistors in this amplifier are npn, consid- eration must be taken when stabilizing the output. a one ohm resistor, 0.1uf capacitor snubber network should be added ex- ternally from the output to -vcc on each amplifier. this con- figuration minimizes local output stage oscillations. as always, adequate power supply bypassing is a necessity for ampli- fier stability. a parallel combination of a 4.7uf electrolytic (for every amp of output current) and a 0.01uf ceramic disc capaci- tor should be connected as close as possible to the package power supply pins to ground. if the inductive load is driven near steady state conditions al- lowing the output to drop more than 6v below the supply rail while the amplifier is current limiting, the inductor should be capacitively coupled or the supply voltage must be lowered to meet the soa criteria. it is a good practice to also connect reverse biased fast recovery diodes to the output for protection against sustained high energy flyback. vcc 20v 15v 10v 5v capacitive load 200uf 500uf 5mf 50mf inductive load 7.5mh 25mh 35mh 150mh safe operating area curves are a graphical representation of all of the power limiting factors involved in the output stage of an operational amplifier. three major power limiting factors are; output transistor wire bond carrying capability, output transis- tor junction temperature and secondary breakdown effects. to see if your application is meeting or exceeding the limitations of the safe operating area curves, perform the following steps: 1. find the worst case output power dissipation. for a split supply, purely resistive load application, this occurs when v out =1/2 v cc . 2. take the values of (v cc -v out ) and the corresponding out- put current and find their intersection on the safe operating area curves. 3. verify this point is below the safe operating area curves. this is a simple task for purely resistive loads, for reactive loads the following table will save extensive analysis. under tran- sient conditions, capacitive and inductive loads up to the fol- lowing maximum are usually safe. parallel connection yields single 4a amplifier bidirectional motor drive 3 rev. h 8/00
application notes continued heat sinking to determine if a heat sink is necessary for your applica- tion and if so, what type, refer to the thermal model and governing equation below. thermal model: 1.) find driver power dissipation p d = [(quiescent current) x (+v cc - (-v cc ))] + [(v cc -v o ) x i out ] = (75ma) x (24v) + (2v) x (0.5a) + (2v) x (0.5a) = 1.8w + 2w = 3.8w 2.) for conservative design, set t j =+150c. 3.) for this example, worst case t a =+25c 4.) r q jc = 3.0c/w 5.) rearrange governing equation to solve for r q sa r q sa = ((t j - t a )/p d ) - (r q jc ) - (r q cs ) = ((150c - 25c) / 3.8w) - (3c/w) @ 29.9c/w the heat sink in this example must have a thermal resis- tance of no more than 30c/w to maintain a junction temperature of no more than +150c . example: in our example the amplifier application requires each out- put to drive a 10 volt peak sine wave across a 20 ohm load for 0.5 amp of output current. for a worst case analysis we will treat the 0.5 amp peak output current as a d.c. output current. the power supplies are 12vdc. the device is the soic version. universal evaluation pc board layout the msk 173 is a highly thermally conductive device and the thermal path from the package to the internal junc- tions is very short. standard surface mount techniques should be used when soldering the device into a circuit board. a hole can be cut in the printed circuit board to allow the heat sink of the package to be thermally bonded to an external heat sink for high power applications. governing equation: t j =p d x (r q jc + r q cs + r q sa ) + t a where t j = junction temperature p d = total power dissipation r q jc = junction to case thermal resistance r q cs = case to heat sink thermal resistance r q sa = heat sink to ambient thermal resistance t c = case temperature t a = ambient temperature t s = sink temperature the heat sink and lid of the msk 173 are electrically con- nected to the negative power supply rail. the user is urged to keep this in mind when designing the printed circuit card the msk 173 will be placed in. there should be no printed circuit traces making contact with the case of the device except for -vcc. the -vcc plane or ground for single supply systems, can be used to pull heat away from the device and must be connected electrically to the heat sink. device soldering case connection 4 rev. h 8/00
typical performance curves 5 rev. h 8/00
mechanical specifications esd triangle indicates pin 1. all dimensions are 0.010 inches unless otherwise labeled. MSK173 6 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. part number MSK173 MSK173b MSK173-1 MSK173b-1 industrial/non-hermetic military-mil-prf-38534 industrial/non-hermetic military-mil-prf-38534 10 pin power soic 10 pin power soic 10 pin flatpack 10 pin flatpack 3.0 3.0 12 12 screening level package style q q q q q jc (c/w) ordering information m.s. kennedy corp. 4707 dey road, liverpool, new york 13088 phone (315) 701-6751 fax (315) 701-6752 www.mskennedy.com MSK173-1 rev. h 8/00
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