8170 thompson road cicero, n.y. 13039 m.s.kennedy corp. (315) 699-9201 features: ultra fast rise time - 2.8ns typical wide bandwidth - 200 mhz typical variable gain - 0 to 100 v/v on board reference output 50 vpp output voltage swing blanking capability user adjustable brightness and contrast 25,000 v/sec slew rate replaces tp1900 and max 445 high performance, high voltage video display driver 1900 high resolution mono-chrome displays high resolution rgb displays high speed, high voltage amplification for ate typical applications pin-out information 1 2 3 4 5 6 7 8 ground v ref v off v gain ground +input -input v ee 9 10 11 12 13 14 15 16 v ee v cc blank ground ground ground ground v cb description: the msk 1900 is a high performance, high voltage, variable gain video amplifier capable of directly driving high resolu- tion video displays. the msk 1900 features differential inputs and a linearly adjustable gain stage with an output offset adjustment which allows it to be a versatile performer well suited for many applications. a ttl level blanking input is available to set the output to a predetermined black level independent of signal input. the msk 1900 is packaged in a cost effective, 24 pin power dip which can be bolted directly to a heat sink for efficient thermal management. equivalent schematic iso-9001 certified by dscc 1 rev. b 9/99 17 18 19 20 21 22 23 24 v cb n/c output v ee v ee ground ground ground note: all pins must be connected for proper operation if labeled.
static quiescent current high voltage supply thermal resistance to case input input bias current common base current blank input current offset adjust input current gain adjust input current blank input pulse width common mode rejection ratio input impedance input capacitance blank mode input rejection d v gain adjust rejection d v power supply rejection ratio output reference output voltage output current blank mode output current (min offset) output current (max offset) voltage gain (rp=200 w ) bandwidth transition times linearity error gain linearity thermal distortion absolute maximum ratings storage temperature range lead temperature range (solder 10 seconds) junction temperature case operating temperature msk 1900 thermal resistance (junction to case) -25c to +150c +300c +150c 0c to +70c 7.5c/w +v hv +v cc -v ee v id v gain v off v blank v cb electrical specifications parameter 2 tc=25c unless otherwise specified 1 test conditions typ. 55 -75 60 8 1 30 500 300 2 2 - 40 20k 2 - - 30 5.5 0 10 100 100 225 2.8 - - - msk 1900 min. - - 20 - - - - - - - 30 - 10k - - - 25 5.2 -3 0.5 80 80 - - - - - units 2 2 2 2 2 2 2 high voltage supply(wrt vcb) positive supply voltage negative supply voltage differential input voltage gain adjust input voltage offset adjust input voltage blank input voltage common base supply +65v +12v -12v 2v -0.6v to +6v -0.6v to +6v -0.6v to +6v 20v t st t ld t j t c o jc 2 2 2 2 3 2 3 2 1 2 3 4 +v cc = +10v, -v ee = -10.5v, +v hv = +70v, v cb = +10v, v blank = 0.4v, c l = 6pf, rp = 200 w , v gain = v off = v in = 0v unless otherwise specified. parameters shall be guaranteed by design if not tested. typical parameters are representative of actual device performance but are for reference only. faster rise times are obtained without using test sockets. in addition, a peaking network must be used to achieve best perform ance. output voltage d v is the difference between +v hv and v out . notes: v cm =0v@+10v v cm =0v@-10.5v wrt v cbb v cm =0v v cb =10v v blank =0.4v v blank =2.4v v off =1v v gain =5v normal operation v cm =0.5v f=10hz either input f=dc either input v blank =2.4v v in =0.3v d v gain =5v +v cc and -vee=nom 5% i out <2ma v blank =2.4v v off =1v v gain =0v v off =0v v gain =5v v off =5v v gain =0v v in =0.6v f=10khz v gain =5v either input v off =0v v gain =3v t r =t f <0.5ns v off =1v v gain =1v v off =1v v cm =0.5v v off =1v v in =0.2v v cm =0.5v max. 70 -100 65 10 50 40 600 400 10 10 - - - - 0.4 2.0 - 5.8 +3 25 120 120 - - 2 2 2 ma ma v c/w a ma a a a a ns db w pf v v db v ma ma ma v/v mhz ns %gs % %gs 2 2 2 2 2 rev. b 9/99 4 4 2
the v gain control (contrast) input is designed to allow the user to vary the video gain. by simply applying a dc voltage from 0v to v ref , the video gain can be linearly adjusted from 0 to 100v/v. the v gain input should be connected to the v ref pin through a 5k w pot to ground. for convenient stable gain adjustment, a 0.1f bypass capacitor should be connected near the v gain input pin to prevent output instability due to noisy sources. digital gain control can be accomplished by connect- ing a d/a converter to the v gain pin. however, some tempera- ture tracking performance may be lost when using an external dc voltage source other than v ref for gain adjustment. the overall video output of the msk 1900 can be charac- terized using the following expression: vpp=v hv -v out v hv -v out =(v in )(v gain )(rp)(0.08) here is a sample calculation for the MSK1900: given information v in =0.7v v gain =1vdc rp=200 w (external) v hv =70vdc v hv -v out =(0.7v)(1v)(.08)(200 w ) v hv -v out =11.2vpp nominal the expected video output would swing from approximately +70v to +58.8v assuming that v off =0v. this calculation should be used as a nominal result because the overall gain may vary as much as 10% due to internal high speed device varia- tions. changing ambient conditions can also effect the video gain of the amplifier slightly. it is wise to connect all video amplifiers to a common heat sink to maximize thermal tracking when multiple amplifiers are used in applications such as rgb systems. additionally, only one of the v ref outputs should be shared by all three amplifiers. this voltage should be buffered with a suitable low-drift op-amp for best tracking performance. application notes power supplies the input stage of the msk 1900 requires power supplies of +10v and -10.5v for optimum operation. the negative power supply can be increased to -12v if -10.5v is not available, but additional power dissipation will cause the internal temperature to rise. both low voltage power supplies sould be effectively decoupled with tantalum capacitors (at least 1f) connected as close to the amplifiers pins as possible. the msk 1900 has internal 0.01f capacitors that also improve high frequency per- formance. additionally, it is also recommended to put 0.1f decoupling capacitors on the +10v and -10.5v supplies as well. the high voltage power supply (+v hv ) is connected to the amplifiers output stage and must be kept as stable as possible. the internal rp is connected to +v hv and as such, the amplifi- ers dc output is directly related to the high voltage value. the +v hv pin of the hybrid should be decoupled to ground with as large a capacitor as possible to improve output stability. v gain control input video inputs the analog inputs (v in ) are designed to accept rs343 signals, 0.714v pp , and operate properly with a common mode range of 0.5v with respect to ground. therefore, it is recom- mended that the input signal be limited to 1.3v with respect to ground, (signal + common mode). although large offsets of 2v (with respect to ground, signal included) can be tolerated without damage to the hybrid, output linearity suffers and there- fore it is not recommended. the output pin of the msk 1900 can be protected from tran- sients by connecting reversed biased ultra-low capacitance di- odes from the output pin to both +v hv and ground. the output can also be protected from arc voltages by inserting a small value (50-100 w ) resistor in series with the amplifier. this resistor will reduce system bandwidth along with the load capacitance, but a series inductor can reduce the problem substantially. output protection video output when power is first applied and v in =v gain =v off =0v, the output will be practically at the +v hv rail voltage. the output voltage is a function of the value of rp and also the v gain and v off dc inputs. the bandwidth of the amplifier largely depends on both rp and lp. with +v hv set to +70v and total rp=200 w , the device is capable of approximately 62vpp total output swing. the msk 1900 is conservatively specified with low values for external lp which yield about 5% overshoot. additional peaking can be obtained by using a high self-resonant frequency inductor in series with +v hv pin. since this value of inductance can be very dependent on circuit layout, it is best to determine its value by experimentation. a good starting point is typically 0.47h for the msk 1900. supply sequencing the power supply sequence is +v hv , v cc , v ee followed by the other dc control inputs. if power supply sequencing is not possible, the time difference between each supply should be less than five milliseconds. if the dc control signals are being generated from a low impedance source other than the v ref output, reverse biased diodes should be connected from each input (v gain , v off ) to the +v cc pin. this will protect the inputs until +v cc is turned off. 3 rev. b 9/99 v cb the v cb input is the base connection to the output stage con- sisting of a common base, high voltage stage and a high speed, low voltage current amplifier in a cascode arrangement. this input requires a very stable 10v dc nominal voltage. any ac signals at this point will be amplified and reflected in the output. the psrr of the output stage is directly related to the stability of this v cb voltage.
(t c = 25c, v hv = 70v, r p = 200 w w w w w ) application notes con't 0 100 80 80 0 35 35 50 1.6 7.8 6.5 5.6 0 6.1 4.9 10 1.6 13.9 11.4 15.6 the video input can be electrically disconnected from the amplifier by applying a ttl high input to the blank pin. when this occurs, the output will be set to approximately +v hv . the v gain and v off control pins have little or no effect on the output when it is in blank mode. when the ttl compatible blank input is not used, the pin must be connected to ground to enable the amplifier. the blank input will float high when left unconnected which will disable the video. blank input the msk 1900 has an on board buffered dc zener reference output. the v ref output is nominally 5.5v dc and has full temperature test limits of 5.2v to 5.8v dc. this output is provided for gain and offset adjustment and can source up to 4ma of current. v ref output total p d watts v o - v black ic p d watts p load watts the msk 1900 package is electrically isolated from the inter- nal circuitry, allowing direct connection to a heat sink. the power dissipation of the amplifier depends mainly on the load requirements, bandwidth, pixel size, black level and the value of the external rp. refer to the following table for typical power levels for selected video conditions: thermal management 4 rev. b 9/99 the voltage developed across the external load resistor with a 0v video input to the msk 1900 is the black level. this voltage may be changed by adjusting the load resistor or by varying the output quiescent current of the msk 1900 as described in v off above. the black level could also be effected by the v gain con- trol voltage if the video input has a dc component. ac coupling of the video input will prevent this phenomenon from occurring. black level v off is the output offset (brightness) control used to set the output quiescent current and consequently the dc output volt- age (black level). output quiescent current adjustment range is from several a to 100ma nominal (80 to 130 ma actual). normally a 5k potentiometer is connected between v ref and gnd to this input, but any 0 - 5.5v external dc source may be used. a 0.1f capacitor should be connected from this pin to signal ground to improve the amplifier's stability. v off power dissipation table duty cycle %
the connections shown above are for the msk 1900 evaluation board. +vcc should be connected to v cb through a 20 w resister with a 15pf capacitor to ground. this will help to filter power supply noise and provide a stable voltage at v cb . rp is an external component and must not be located near ground planes if possible. a high quality resistor such as bradford electronics p/n fp10-200 is required for optimum response times. typical connection circuit 5 rev. b 9/99
ordering information screening level 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. mechanical specifications m.s. kennedy corp. 8170 thompson rd., cicero, new york 13039-9393 tel. (315) 699-9201 fax (315) 699-8023 part number industrial MSK1900 all dimensions are .010 inches unless otherwise labeled 6 rev. b 9/99 www.mskennedy.com
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