ULTRA HIGH SPEED/VOLTAGE NEGATIVE OUTPUT VIDEO AMPLIFIER

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1 M.S.KENNEDY CORP. 477 Dey Road Liverpool, N.Y. 88 (1) 7171 FEATURES: Low Cost Complete Amplifier System pp Output Signal Into pf Ultra Fast Transition pp User Adjustable Contrast and Brightness TTL Compatible Blanking On Board DC Reference Output Customized ersions Readily Available Available with Three Lead Bend Options ISO91 CERTIFIED BY DSCC 19 SERIES MILPRF84 CERTIFIED DESCRIPTION: The MSK 19 Series of High Speed, High oltage ideo Amplifiers are designed to drive the grid of today's high performance CRTs. The MSK 19 has user adjustable contrast and brightness levels and also comes with a blanking function. The MSK 19 can be directly connected to many video sources including RS17, RS4 and high speed video D/A converters. The MSK 19 is available in four versions for different applications. The MSK 19 has no internal high voltage resistor or inductor allowing the user to dissipate much of the power externally. The MSK 19, MSK 194 and the MSK 19 each have an internal resistorinductor designed for optimum bandwidth. The MSK 19 has slightly lower bandwidth but can be operated from up to. Each version of the MSK 19 is packaged in an isolated pin insulated ceramic substrate that can be directly connected to a heat sink using standard mounting techniques. The leads are available straight out, bent up or bent down. EQUIALENT SCHEMATIC ULTRA HIGH SPEED/OLTAGE NEGATIE OUTPUT IDEO AMPLIFIER TYPICAL APPLICATIONS PINOUT INFORMATION Helmet Mounted Displays High Resolution RGB Displays High Resolution Monochrome Displays Automatic Test Equipment Medical Monitors CAE/CAD Station Monitors Projection Displays Beam Index Displays Blank EE Input +Input Gain off ref RES RES Output NC cc cc Rev. C /

2 ABSOLUTE MAXIMUM RATINGS CC EE IN IC GAIN OFF High oltage Supply (19) (19) (194) (19) Positive Supply oltage Negative Supply oltage Differential Input oltage Common Mode Input oltage Gain Adjust Input oltage Offset Adjust Input oltage ±. to +. to + BLANK IREF TST TLD TJ IRP TC Blank Input oltage Reference Output Current Storage Temperature Range Lead Temperature Range ( Seconds) Junction Temperature Current Through Rp Case Operating Temperature (All Devices). to + ma C to + C C C 9mA C to +1 C ELECTRICAL SPECIFICATIONS STATIC Input Bias Current Offset Adjust Input Current 7 Gain Adjust Input Current 7 Blank Input Pulse Width Common Mode Rejection Ratio CM=±. F=Hz Input Impedance Either Input F=DC Input Capacitance Blank Mode Input Either Input BLANK=.4 IN=. Rejection 4 =HOUT Gain Adjust Rejection 4 GAIN= Power Supply Rejection Ratio +CC and EE=Nom ±% Internal Rp OUTPUT 4 NOTES: Parameter Quiescent Current High oltage Supply Thermal Resistance to Case INPUT Blank Input Current 8 Test Conditions 1 + QOUT and QCAS CM= BLANK=.4 BLANK=.4 OFF=1 GAIN= Normal Operation MSK19 MSK19 Min. Typ. Max. Min. Typ. Max. K K Reference Output oltage IOUT<mA Blank Mode 4 =HOUT OFF=1 BLANK=.4 GAIN= xrp Rp xrp xrp Rp xrp xrp Rp xrp xrp Rp xrp m Min Offset Max Offset =HOUT OFF= GAIN= =HOUT OFF= oltage Gain IN=. F=KHz GAIN= Both Inputs / Output oltage High Output oltage Low GAIN= F=KHz GAIN= F=KHz Transistion Times 7 IN=. TR=TF<.nS ns Linearity Error Gain Linearity GAIN =4 OFF=1 CM=. OFF=1 IN=. CM=. ± ± ± ± ± ± ± ± %GS % Thermal Distortion ± ± ± ± %GS +CC = +, EE =., BLANK = GAIN = OFF = ±IN =, CL=pF, TC= C unless otherwise specified. H=Typical alue for each dash number for all parameters. This parameter is guaranteed by design but need not be tested. Typical parameters are representative of actual device performance but are for reference only. RP=Internal RP except MSK 19. External value = Ω unless otherwise specified for the MSK 19. is defined as the difference between and the output. Parameter is % tested on production devices. Parameter is sample tested in accordance with MSK industrial grade quality devices. When the output is amplifying a video signal, the output current will be present at +CC and since the output is referred to +CC internally. 9 ± ±xrp ±xrp K K 9 ± ±xrp ±xrp MSK194 MSK19 Units Min. Typ. Max. Min. Typ. Max. K K 7 ± ±xrp ±xrp K K ma ma C/W ± ±xrp ±xrp ns db Ω pf m m db Ω Rev. C /

3 APPLICATION NOTES POWER SPLIES The input stage of the MSK 19 requires power supplies of + and. for optimum operation. The negative power supply can be increased to 1 if. is not available, but additional power dissipation will cause the internal temperature to rise. Both low voltage power supplies should be effectively decoupled with tantalum capacitors (at least 4.7µF) connected as close to the amplifier's pins as possible. The MSK 19 has internal.1µf capacitors that also improve high frequency performance. It is also recommended to put.1µf decoupling capacitors on the + and. supplies as well. Since the output stage is returned to + internally, all of the output current will flow through this supply pin. The high voltage power supply () is connected to the amplifier's output stage and must be kept as stable as possible. The internal or external Rp is connected to and as such, the amplifier's DC output is directly related to the high voltage value. The pins of the hybrid should be decoupled to ground with as large a capacitor as possible to improve output stability. SPLY SEQUENCING The power supply sequence is H, CC, 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 REF output, reverse biased diodes should be connected from each input (GAIN, OFF) to the CC pin. This will protect the inputs until CC is turned on. IDEO OUTPUT When power is first applied and IN=GAIN=OFF=, the output will be practically at the rail voltage. The output voltage is a function of the value of Rp and also the GAIN and OFF DC inputs. The maximum output voltage swing for any of the MSK 19 variants is determined by pp = (ma) x (Rp). The bandwidth of the amplifier largely depends on both Rp and Lp. Hybrid pins 1 and 1 are directly connected to Rp. Additional external resistance can be added to reduce power dissipation, but slower transition times will result. If an additional resistor is used, it must be low capacitive and the layout should minimize capacitive coupling to ground (ie: no ground plane under Rp). IDEO INPUTS The video input signals should be kept below ±MAX total, including both common mode offset and signal levels. The input structure of the MSK 19 was designed for ±.714pp RS4 signals. If either input is not used it should be connected directly to the analog ground or through a Ω resistor to ground if input offset currents are to be minimized. OUTPUT PROTECTION The output pin of the MSK 19 should be protected from transients by connecting reversed biased ultralow capacitance diodes from the output pin to both and ground. The output can also be protected from arc voltages by inserting a small value (Ω) 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. GAIN CONTROL INPUT The GAIN control (contrast) input is designed to allow the user to vary the video gain. By simply applying a DC voltage from to REF, the video gain can be linearly adjusted from to 19/ (MSK 19). The GAIN input should be connected to the REF pin through a KΩ pot to ground. For convenient stable gain adjustment, a.1µf bypass capacitor should be connected near the GAIN input pin to prevent output instability due to noisy sources. Digital gain control can be accomplished by connecting a D/A converter to the GAIN pin. However, some temperature tracking performance may be lost when using an external DC voltage source other than REF for gain adjustment. The bandwidth of the GAIN input is approximately 1MHz. The overall video output of the MSK 19 can be characterized using the following expression: pp=hout HOUT=(IN)(GAIN)(Rp)(.9) (or) oltage Gain=OUT/IN=(GAIN)(Rp)(.9) Here is a sample calculation for the MSK 19: Given information IN=.7 GAIN=1DC Rp=Ω (internal) H=8DC HOUT=(.7)(1)(Ω)(.9) HOUT=. Nominal The MSK 19 Series is conservatively specified with low values for Lp which yield about % overshoot. Additional peaking can be obtained by using a high selfresonant frequency inductor in series with pins 1 & 1. 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.47µh for the MSK 19 and.47µh for the remaining devices. If external resistors or inductors are not used, be sure to connect high frequency bypass capacitors directly from pins 1 and 1 to ground for the devices that contain an internal Rp. The expected video output would swing from approximately 8 to 4.8 assuming that OFF=. This calculation should be used as a nominal result because the overall gain may vary as much as ±% due to internal high speed device variations. Changing ambient conditions can also effect the video gain of the amplifier by as much as PPM/ C. 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 REF outputs should be shared by all three amplifiers. This voltage should be buffered with a suitable low drift opamp for best tracking performance. Rev. C /

4 APPLICATION NOTES CON'T OFF CONTROL INPUT The brightness (output offset) can be linearly adjusted by applying a to REF DC voltage to the OFF input pin. The output quiescent voltage range is from approximately ()(Rp) to (ma)(rp) from. This control voltage is normally generated by connecting the OFF control pin to a K potentiometer between REF and ground. The OFF input pin should be bypassed with a.1µf capacitor to ground placed as close as possible to the hybrid. This DC voltage can be any stable system source. The bandwidth of the OFF pin is approximately 1MHz. Keep hybrid power dissipation in mind when adjusting the output quiescent voltage. Practically all of the voltage is seen across Rp! This power must be taken into account when high Rp currents are used. If the quiescent level is set too close to, the power dissipation will be minimal but the rise time will suffer slightly. If the quiescent level is set too far from, the power dissipation will increase dramatically and the output fall time will be limited. The output black level is obviously dependent on system requirements but a little experimentation will strike the optimum balance between power dissipation and bandwidth. Total current through Rp should be limited to less than 9mA when operating from power supplies greater than 9. The gain adjust alone can set the AC current to ma (ie: mapp=pp/ω). Typically, most applications use about from for a black level. BLANK INPUT The video input can be electrically disconnected from the ampliifer by applying a TTL high input to the blank pin. When this occurs, the output will be set to approximately. The GAIN and 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. REF OUTPUT The MSK 19 has an on board buffered DC zener reference output. The REF output is nominally. DC and has full temperature test limits of. to.8 DC. This output is provided for gain and offset adjustment and can source up to 4mA of current. THERMAL MANAGEMENT The MSK 19 package has mounting holes that allow the user to connect the amplifier to a heat sink or chassis. Since the package is electrically isolated from the internal circuitry, mounting insulators are not required or desired for best thermal performance. Use 4 to inch/pounds for mounting the device to the heat sink. The power dissipation of the amplifier depends mainly on the load requirements, bandwidth, pixel size, black level and the value of Rp. The following table illustrates a few examples: DEICE TYPE BLACK LEEL 1 1 WHITE LEEL 1 1 OUTPUT OLTAGE 9 BLANK % % % % PERCENT OF SIGNAL BLACK % % % % RESOLUTION TABLE FOR TYPICAL CRT'S WHITE % % % % OUTPUT AE. Pd W 1.W W 8.4W TOTAL AE. Pd.W 1.7W.W.W This table does not include power dissipation due to output switching since this is dependent on individual load requirements. The input stage power dissipation is typically. watts and is essentially independent of output levels. Display Resolution Maximun Pixel Time Minimum Pixel Clock Frequency Required Rise Time at CRT Required System Bandwidth (FdB) x x x 48 8 x 4 x 9 4 x 4 18 x 4 14 x 48 x 48 9 x 18nS ns 8nS ns 1.nS 11nS 8.9nS.8nS.8nS 8pS MHz 19MHz MHz 8MHz 8MHz 9MHz 11MHz 17MHz MHz 1.GHz All data assumes retrace time equal to % of frame time and a Hz refresh rate. 4 ns 17nS 1.nS 8.nS 4.nS.7nS.9nS 1.9nS 1nS 8pS MHz MHz 8MHz 41MHz 84MHz 9MHz MHz 18MHz 8MHz 1.GHz Rev. C /

5 TYPICAL CONNECTION CIRCUIT The connection circuit shown above is for the MSK 19 evaluation board. The Rp and Lp are external components and must not be located near ground planes if possible. A high quality resistor such as Bradford Electronics P/ N FP is required for optimum response times. Use an inductor with a high selfresonant frequency that can withstand the currents required for the application. When using the other variants of the MSK 19, place an additional bypass capacitor on pins 1 and 1 if series (Rp and Lp) components are not utilized. The pin should connect to with a short low impedance path. For additional applications information, please contact the factory. Evaluation amplifiers with test boards are readily available for MSK. NOTES: Rev. C /

6 MECHANICAL SPECIFICATIONS ESD TRIANGLE INDICATES PIN 1. TORQUE SPECIFICATION 4 TO IN/LBS. ALL DIMENSIONS ARE ±. INCHES UNLESS OTHERWISE LABELED. ORDERING INFORMATION PART NUMBER LEAD OPTION MAX INTERNAL RP TYPICAL RISE TIME SCREENING LEEL MSK 19S MSK 19D MSK 19U MSK 19S MSK 19D MSK 19U MSK 19S4 MSK 19D4 MSK 19U4 MSK 19S MSK 19D MSK 19U NONE Ω Ω Ω 4.nS.8nS.9nS.nS M.S. Kennedy Corp. 477 Dey Road, Liverpool, New York 88 Phone (1) 7171 FAX (1) 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. Rev. C /