ISO-9001 CERTIFIED BY DSCC M.S.KENNEDY CORP. HIGH PERFORMANCE, HIGH VOLTAGE VIDEO DISPLAY DRIVER 1900 8170 Thompson Road Cicero, N.Y. 13039 (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/µSec Slew Rate Replaces TP1900 And Max 445 DESCRIPTION: The MSK 1900 is a high performance, high voltage, variable gain video amplifier capable of directly driving high resolution 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 TYPICAL APPLICATIONS PIN-OUT INFORMATION 1 2 3 4 5 6 7 8 High Resolution Mono-Chrome Displays High Resolution RGB Displays High Speed, High Voltage Amplification for ATE Ground VREF VOFF VGAIN Ground +Input -Input VEE 9 10 11 12 13 14 15 16 VEE VCC Blank Ground Ground Ground Ground VCB 17 18 19 20 21 22 23 24 VCB N/C Output VEE VEE Ground Ground Ground NOTE: All pins must be connected for proper operation if labeled. 1 Rev. B 9/99 ABSOLUTE MAXIMUM RATINGS +VHV +VCC -VEE VID VGAIN VOFF VBLANK VCB 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 ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ TST Storage Temperature Range TLD Lead Temperature Range (Solder 10 Seconds) TJ Junction Temperature TC Case Operating Temperature MSK 1900 OJC Thermal Resistance (Junction to Case) ○ ○ ○ ○ ○ ○ +65V +12V -12V 2V -0.6V to +6V -0.6V to +6V -0.6V to +6V 20V ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ELECTRICAL SPECIFICATIONS Parameter ○ ○ ○ ○ -25°C to +150°C +300°C ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ +150°C 0°C to +70°C 7.5°C/W ○ ○ ○ Tc=25°C unless otherwise specified Test Conditions 1 MSK 1900 Units Min. Typ. Max. VCM=0V@+10V - 55 70 mA [email protected] - -75 -100 mA WRT VCBB 20 60 65 V - 8 10 °C/W ±1 ±50 µA STATIC Quiescent Current HIgh Voltage Supply 2 Thermal Resistance to Case 2 INPUT Input Bias Current 2 VCM=0V - Common Base Current 2 VCB=10V - 30 40 mA VBLANK=0.4V - 500 600 µA VBLANK=2.4V - 300 400 µA Offset Adjust Input Current 2 VOFF=1V - 2 10 µA Gain Adjust Input Current 2 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 ∆V GAIN=5V - - ±2.0 V +VCC and -Vee=Nom ±5% 25 30 - dB IOUT<2mA 5.2 5.5 5.8 V Output Current Blank Mode VBLANK=2.4V VOFF=1V VGAIN=0V -3 0 +3 mA Output Current (Min Offset) VOFF=0V VGAIN=5V 0.5 10 25 mA Output Current (Max Offset) VOFF=5V VGAIN=0V 80 100 120 mA VIN=0.6V F=10KHz VGAIN=5V Either Input 80 100 120 V/V VOFF=0V - 225 - MHz VGAIN=3V TR=TF<0.5nS VOFF=1V - 2.8 - nS VGAIN=1V VOFF=1V VCM=0.5V - - ±2 %GS VOFF=1V VIN=0.2V VCM=0.5V - - ±2 % - - ±2 %GS Blank Input Current 2 Blank Input Pulse Width 2 Common Mode Rejection Ratio 2 Input Impedance 2 Input Capacitance 2 Blank Mode Input Rejection ∆V 2 4 Gain Adjust Rejection ∆V 2 4 Power Supply Rejection Ratio 2 OUTPUT Reference Output Voltage Voltage Gain (Rp=200Ω) Bandwidth 2 3 Transition Times 2 3 Linearity Error 2 Gain Linearity 2 Thermal Distortion 2 NOTES: 1 +VCC = +10V, -VEE = -10.5V, +VHV = +70V, VCB = +10V, VBLANK = 0.4V, CL = 6pF, Rp = 200Ω, VGAIN = VOFF = ±VIN = 0V unless otherwise specified. 2 Parameters shall be guaranteed by design if not tested. Typical parameters are representative of actual device performance but are for reference only. 3 Faster rise times are obtained without using test sockets. In addition, a peaking network must be used to achieve best performance. 4 Output voltage ∆V is the difference between +VHV and VOUT. 2 Rev. B 9/99 APPLICATION NOTES POWER SUPPLIES VIDEO INPUTS 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 1µF) connected as close to the amplifiers pins as possible. The MSK 1900 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 analog inputs (±VIN) are designed to accept RS343 signals, ±0.714VPP, and operate properly with a common mode range of ±0.5V with respect to ground. Therefore, it is recommended 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 therefore it is not recommended. OUTPUT PROTECTION The output pin of the MSK 1900 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 VCB 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. The VCB input is the base connection to the output stage consisting 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 VCB voltage. SUPPLY SEQUENCING The overall video output of the MSK 1900 can be characterized using the following expression: 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. Vpp=VHV-VOUT VHV-VOUT=(VIN)(VGAIN)(Rp)(0.08) Here is a sample calculation for the MSK1900: Given information VIN=0.7V VGAIN=1VDC Rp=200Ω (external) VHV=70VDC VHV-VOUT=(0.7V)(1V)(.08)(200Ω) VHV-VOUT=11.2Vpp Nominal VIDEO OUTPUT 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, the device is capable of approximately 62Vpp total output swing. 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 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 +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 1900. 3 Rev. B 9/99 APPLICATION NOTES CON'T VOFF BLANK INPUT VOFF is the output offset (brightness) control used to set the output quiescent current and consequently the DC output voltage (black level). Output quiescent current adjustment range is from several µA to 100mA nominal (80 to 130 mA actual). Normally a 5K potentiometer is connected between VREF and GND to this input, but any 0 - 5.5V external DC source may be used. A 0.1µF capacitor should be connected from this pin to signal ground to improve the amplifier's stability. 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. VREF OUTPUT THERMAL MANAGEMENT The MSK 1900 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. The MSK 1900 package is electrically isolated from the internal 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: POWER DISSIPATION TABLE Ω) (TC = 25°C, VHV = 70V, RP = 200Ω BLACK LEVEL 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 VOFF above. The black level could also be effected by the VGAIN control voltage if the video input has a DC component. AC coupling of the video input will prevent this phenomenon from occurring. VO - VBLACK 4 Duty Cycle % IC PD Watts PLOAD Watts TOTAL PD Watts 1.6 0 0 1.6 0 35 100 7.8 6.1 13.9 35 80 6.5 4.9 11.4 50 80 5.6 10 15.6 Rev. B 9/99 TYPICAL CONNECTION CIRCUIT The connections shown above are for the MSK 1900 evaluation board. +Vcc should be connected to VCB through a 20Ω resister with a 15pF capacitor to ground. This will help to filter power supply noise and provide a stable voltage at VCB. 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. 5 Rev. B 9/99 MECHANICAL SPECIFICATIONS ALL DIMENSIONS ARE ±.010 INCHES UNLESS OTHERWISE LABELED ORDERING INFORMATION Part Number Screening Level MSK1900 Industrial M.S. Kennedy Corp. 8170 Thompson Rd., Cicero, New York 13039-9393 Tel. (315) 699-9201 FAX (315) 699-8023 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. B 9/99