ISO-9001 CERTIFIED BY DSCC M.S.KENNEDY CORP. HIGH PERFORMANCE, HIGH VOLTAGE VIDEO DISPLAY DRIVER 1911 4707 Dey Road Liverpool, N.Y. 13088 (315) 701-6751 FEATURES: MIL-PRF-38534 CERTIFIED Internal Load Resistor for Highest Bandwidth Ultra Fast Rise Time - 2.0nS Typical Wide Bandwidth - 225 MHz Typical Variable Gain - 0 to 100 V/V On Board Reference Output 60 Vpp Output Voltage Swing Blanking Capability User Adjustable Brightness and Contrast 25,000 V/µSec Slew Rate Low Cost Complete Video CRT Driver System DESCRIPTION: The MSK 1911 is a high performance, high voltage, variable gain video amplifier capable of directly driving high resolution video displays. The MSK 1911 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 1911 is packaged in a cost effective, highly thermally conductive, insulated package which can be bolted directly to a heat sink for efficient thermal management. EQUIVALENT SCHEMATIC TYPICAL APPLICATIONS PIN-OUT INFORMATION High Resolution Mono-Chrome Displays High Resolution RGB Displays High Speed, High Voltage Amplification for ATE 1 2 3 4 5 6 7 1 Ground Blank VCC VEE -Input +Input Ground 8 9 10 11 12 13 VGAIN VOFF VREF Ground Output +VHV Rev. D 8/00 ABSOLUTE MAXIMUM RATINGS +VHV +VCC -VEE VID VGAIN VOFF VBLANK IREF High Voltage Supply Positive Supply Voltage Negative Supply Voltage Differential Input Voltage Gain Adjust Input Voltage Offset Adjust Input Voltage Blank Input Voltage Reference Output Current ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ +75V +12V -12V 2V -0.6V to +6V -0.6V to +6V -0.6V to +6V 5mA ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ TST Storage Temperature Range -65°C to +150°C TLD Lead Temperature Range +300°C (Solder 10 Seconds) TJ Junction Temperature +175°C PD Total Power Dissipation 13W (Tc=25°C) TC Case Operating Temperature MSK 1911 -25°C to +85°C ○ ○ ○ ○ ○ ○ ○ ○ ○ ELECTRICAL SPECIFICATIONS Parameter ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Tc=25°C unless otherwise specified Test Conditions 1 MSK 1911 Units Min. Typ. Max. VCM=0V@+10V - 85 110 mA [email protected] - -75 -100 mA TC≤85°C 50 70 75 V - 3.2 7 °C/W VCM=0V TC=25°C - ±1 ±50 µA 5 VCM=0V Full Temp. - ±5 ±250 µA VBLANK=0.4V - 500 600 µA VBLANK=2.4V - 300 400 µA Offset Adjust Input Current 2 5 VOFF=1V - 2 10 µA Gain Adjust Input Current 2 5 VGAIN=5V - 2 10 µA Normal Operation 30 - - nS VCM=±0.5V F=10Hz - 40 - dB Either Input F=DC 10K 20K - Ω Either Input - 2 - pF VBLANK=2.4V VIN=0.3V - - ±0.4 V ∆VGAIN=5V - - ±2.0 V +VCC and -Vee=Nom ±5% 25 30 - dB IOUT<2mA 5.2 5.5 5.8 V VBLANK=2.4V VOFF=1V VGAIN=0V -0.4 0 +0.4 V VOFF=0V VGAIN=5V 0.1 2.0 8.0 V STATIC Quiescent Current 4 HIgh Voltage Supply 2 Thermal Resistance to Case INPUT Input Bias Current Blank Input Current 2 2 Blank Input Pulse Width 2 Common Mode Rejection Ratio 2 Input Impedance 2 Input Capacitance 2 Blank Mode Input Rejection ∆V 2 Gain Adjust Rejection ∆V 2 Power Supply Rejection Ratio 2 OUTPUT Reference Output Voltage 4 Output Voltage Blank Mode ∆V 4 6 Output Voltage (Min Offset) ∆V 6 Output Voltage (Max Offset) ∆V 2 6 VOFF=5V VGAIN=0V 12 20 28 V Voltage Gain 4 VIN=0.5V F=10KHz VGAIN=5V 80 100 120 V/V Bandwidth 2 3 Either Input 200 225 - MHz VOFF=0V - 2.0 - nS Transition Times 2 3 Linearity Error 2 VGAIN=3V TR=TF<0.5nS VOFF=1V - - ±2 %GS Gain Linearity 2 VGAIN=1V VOFF=1V VCM=0.5V - - ±2 % Thermal Distortion 2 VOFF=1V VIN=0.2V VCM=0.5V - - ±2 %GS NOTES: 1 +VCC = +10V, -VEE = -10.5V, +VHV = +70V, VBLANK = 0.4V, CL = 2pF, VGAIN = VOFF = ±VIN = 0V unless otherwise specified. 2 These parameters are guaranteed by design but need not be tested. Typical parameters are representative of actual device performance but are for reference only. 3 Much faster rise times are obtained without using test sockets. In addition, a peaking network may be used to improve overall bandwidth. 4 This parameter is tested 100% on production devices. 5 This parameter is sample tested in accordance with MSK industrial grade quality levels. 6 Output voltage ∆V is the difference between +VHV and VOUT. 2 Rev. D 8/00 APPLICATION NOTES POWER SUPPLIES VIDEO INPUTS The input stage of the MSK 1911 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 should be effectively decoupled with tantalum capacitors (at least 1µF) connected as close to the amplifiers pins as possible. The MSK 1911 has internal 0.01µF capacitors that also improve high frequency performance. Additionally, it is also recommended to put 0.1µF decoupling capacitors on the +10V and -10.5V supplies as well. The video input signals should be kept below ±2VMAX total including both common mode offset and signal levels. The input structure of the MSK 1911 was designed for ±0.714Vpp RS343 signals. If either input is not used it should be connected directly to the analog ground or through a 25Ω resistor to ground if input offset currents are to be minimized. OUTPUT PROTECTION The output pin of the MSK 1911 can be protected from transients by connecting reversed biased ultra-low capacitance diodes from the output pin to both +VHV and ground. The output can also be protected from arc voltages by inserting a small value (50-100Ω) 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. The high voltage power supply (+VHV) is connected to the amplifiers output stage and must be kept as stable as possible. The internal Rp is connected to +VHV and as such, the amplifiers DC output is directly related to the high voltage value. The +VHV pin of the hybrid should be decoupled to ground with as large a capacitor as possible to improve output stability. VGAIN CONTROL INPUT The VGAIN control (contrast) input is designed to allow the user to vary the video gain. By simply applying a DC voltage from 0V to VREF, the video gain can be linearly adjusted from 0 to 100V/V. The VGAIN input should be connected to the VREF pin through a 5kΩ pot to ground. For convenient stable gain adjustment, a 0.1µF bypass capacitor should be connected near the VGAIN input pin to prevent output instability due to noisy sources. Digital gain control can be accomplished by connecting a D/A converter to the VGAIN pin. However, some temperature tracking performance may be lost when using an external DC voltage source other than VREF for gain adjustment. SUPPLY SEQUENCING The power supply sequence is +VHV, VCC, VEE 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 VREF output, reverse biased diodes should be connected from each input (VGAIN, VOFF) to the +VCC pin. This will protect the inputs until +VCC is turned off. The overall video output of the MSK 1911 can be characterized using the following expression: VIDEO OUTPUT Vpp=VHV-VOUT When power is first applied and VIN=VGAIN=VOFF=0V, the output will be practically at the +VHV rail voltage. The output voltage is a function of the value of Rp and also the VGAIN and VOFF DC inputs. The bandwidth of the amplifier largely depends on both Rp and Lp. With +VHV set to +70V and total Rp=200Ω (internal), the device is capable of approximately 62Vpp total output swing. VHV-VOUT=(VIN)(VGAIN)(Rp)(0.08) Here is a sample calculation for the MSK1911: Given information VIN=0.7V VGAIN=1VDC Rp=200Ω (internal) VHV=70VDC VHV-VOUT=(0.7V)(1V)(.08)(200Ω) VHV-VOUT=11.2Vpp Nominal Hybrid pin 13 is 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 capacitance and the layout should minimize capacitive coupling to ground (ie: no ground plane under Rp). The expected video output would swing from approximately +70V to +58.8V assuming that VOFF=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 variations. 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 VREF outputs should be shared by all three amplifiers. This voltage should be buffered with a suitable low-drift op-amp for best tracking performance. The MSK 1911 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 +VHV 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 0.47µH for the MSK 1911. If external resistors or inductors are not used, be sure to connect high frequency bypass capacitors directly from pin 13 to ground. 3 Rev. D 8/00 APPLICATION NOTES CON'T VOFF CONTROL INPUT TRANSITION TIME MINIMIZATION The brightness (output offset) can be linearly adjusted by applying a 0 to VREF DC voltage to the VOFF input pin. The output quiescent voltage range is from approximately (10mA)(200Ω) to (100mA)(200Ω) from +VHV. This control voltage is normally generated by connecting the VOFF control pin to a 5K potentiometer between VREF and ground. The VOFF input pin should be bypassed with a 0.1µF capacitor to ground placed as close as possible to the hybrid. This DC voltage can be any stable system source. To achieve transition times of less than 3 nS with the MSK 1911, all stray and intrinsic capacitances must be compensated for. Two external inductors can accomplish this task easily. (Refer to the figure below). The 200Ω resistor (Rp) and the capacitance of the output driver collector form a high frequency pole which limits the rise and fall time. To compensate for this effect, the series inductor (Lp) is placed in the circuit between the internal Rp and +VHV. A good starting value for this inductor is typically 100nH. Since all applications are slightly different, it is likely that the designer will need to select this inductor value to achieve the desired response. The second inductor (L2) is only necessary when a series CRT isolation resistor (Rs) is used. An inductor in the range of 30nH is placed in series with the resistor to compensate for the pole formed by the resistor and the CRT capacitance. The value of this inductor may be varied as well for optimum response time. 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 almost to +VHV, the power dissipation will be minimal but the rise time will suffer somewhat. If the quiescent level is set too far from +VHV, 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 370mA when operating from power supplies greater than 65V. The gain adjust alone can set the AC current to 250mA (ie: 250mApp=50Vpp/200Ω). THERMAL MANAGEMENT The MSK 1911 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. 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 an example: BLANK INPUT 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 +VHV. The VGAIN and VOFF 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. Typical Power Consumption TC=25°C Ω (Internal) Power Dissipation at +VHV=70V, RP=200Ω VREF OUTPUT VO-VBLACK Duty Cycle % Total PD (Watts) 0 0 1.6 35 100 13.9 35 80 11.4 50 80 15.6 The MSK 1911 has an on board buffered DC zener reference output. The VREF 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. RESOLUTION TABLE FOR TYPICAL CRT'S Display Resolution Maximum Pixel Time 320 x 200 Minimum Pixel Clock Frequency Required Rise Time at CRT Cathode Required System Bandwidth (F-3dB) 182nS 5MHz 60nS 6MHz 640 x 350 52nS 19MHz 17nS 20MHz 640 x 480 38nS 26MHz 12.5nS 28MHz 800 x 560 26nS 38MHz 8.6nS 41MHz 1024 x 900 12.6nS 80MHz 4.2nS 84MHz 1024 x 1024 11nS 90MHz 3.7nS 95MHz 1280 x 1024 8.9nS 112MHz 2.9nS 120MHz 1664 x 1200 5.8nS 170MHz 1.9nS 180MHz 2048 x 2048 2.8nS 360MHz 1nS 380MHz 4096 x 3300 860pS 1.2GHz 280pS 1.23GHz All data assumes retrace time equal to 30% of frame time and a 60Hz refresh rate. 4 Rev. D 8/00 TYPICAL CONNECTION CIRCUIT The connection circuit shown above is for the MSK 1911. Lp is an optional external component and must not be located near ground planes if possible. Use an inductor with a high self-resonant frequency that can withstand the currents required for the application. The ferrite beads should be located as close to the DUT as possible. Fare-Rite Corporation P/N 2743001111 beads work well for most applications. For additional applications information, please contact the factory. Evaluation amplifiers with test boards are readily available from M.S.Kennedy Corp. NOTES: 5 Rev. D 8/00 MECHANICAL SPECIFICATIONS TORQUE SPECIFICATION 3-5 IN./LBS. TEFLON SCREWS OR WASHERS ARE RECOMMENDED ALL DIMENSIONS ARE ±0.010 INCHES UNLESS OTHERWISE LABELED ORDERING INFORMATION Part Number Screening Level MSK1911 Industrial M.S. Kennedy Corp. 4707 Dey Road, Liverpool, New York 13088 Phone (315) 701-6751 FAX (315) 701-6752 www.mskennedy.com 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. 6 Rev. D 8/00