LM1205N National Semiconductor, LM1205N Datasheet
LM1205N
Specifications of LM1205N
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LM1205N Summary of contents
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... Output stage directly drives most hybrid or discrete Y CRT drivers Applications High resolution RGB CRT monitors Y Video AGC amplifiers Wideband amplifiers with gain and DC offset controls Y Interface amplifiers for LCD or CCD systems Y FIGURE 1 Order Number LM1205N See NS Package Number N28B October 1993 TL H 11831 – 24 RRD-B30M115 Printed ...
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... Absolute Maximum Ratings If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office Distributors for availability and specifications Supply Voltage ( Pins (Note 3) Peak Video Output Source Current (Any One Amp) Pins Voltage at Any Input Pin ( Power Dissipation ( (Above 25 C Derate Based on ...
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AC Electrical Characteristics adjust Video Output pins 17 20 and for the AC test unless otherwise stated (Note 15) Symbol Parameter A Video Amplifier Gain V max A Attenuation Attenuation 0 5V ...
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Typical Performance Characteristics Attenuation vs Contrast Voltage Crosstalk vs Frequency Contrast vs Frequency Drive vs Frequency (V 12V unless otherwise specified Attenuation vs Drive Voltage TL H 11831– 11831 – ...
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... Applications Information FIGURE 2 LM1205N DC Test Circuit 11831 – 6 ...
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... Applications Information (Continued) FIGURE 3 LM1205N AC Test Circuit 11831 – 7 ...
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... Applications Information (Continued) FIGURE 4 LM1205N PCB Test Circuit 11831 – 8 ...
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Applications Information (Continued) Figure 5 shows the block diagram of a typical analog RGB color monitor The RGB monitor is used with CAD CAM work stations PC’s arcade games and in a wide range of other applications that benefit from ...
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Functional Description (Continued) The drive control signal comes in on pin 18 Each channel has its own drive section therefore the crosstalk compensation needed for the contrast control voltages is not required for the drive control thus ...
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Functional Description (Continued) FIGURE 6 Block Diagram of LM1205 Video Amplifier FIGURE 7 Timing Diagram Circuit Description VIDEO AMPLIFIER INPUT STAGE Figure simplified schematic of one of the three video amplifiers input stage along with the recommended ...
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Circuit Description (Continued) pensate for beta variations of the transistors Note that the bias voltage passes through three diode drops (Q5 Q6 and Q7) before setting the voltage across and Q4 also provide three diode drops to ...
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Circuit Description (Continued) CONTRAST CONTROL Figure simplified schematic of the Contrast Control circuit The output of this circuit is common to all three chan- nels A reference voltage is generated by Z2 Q34 Q35 R30 and R31 ...
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Circuit Description (Continued) FIGURE 9 Simplified Schematic of LM1205 Contrast Control FIGURE 10 Simplified Schematic of LM1205 Drive Control 11831– 11831– 14 ...
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Circuit Description (Continued) CLAMP COMPARATOR CIRCUIT Figure simplified schematic of the clamp comparator circuit Q85 and its input transistors Q81 and Q82 are one half of the differential pair The base of Q81 is connected to pin ...
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Circuit Description (Continued) FIGURE 11 Simplified Schematic of LM1205 Clamp Comparator Circuit CLAMP GATE CIRCUIT Figure simplified schematic of the Clamp Gate cir- cuit A voltage reference is setup by Z3 and by Q104 and Q105 connected ...
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Circuit Description (Continued) comparators of the three video channels Q103 is added to help drive the base of Q86 in the clamp comparator in- creasing the accuracy of the current mirror Q101 drives R79 and R80 This sets the current ...
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Circuit Description (Continued) FIGURE 13 Simplified Schematic of LM1205 Blank Gate Circuit VIDEO AMPLIFIER OUTPUT STAGE WITH BLANK CIRCUIT Figure simplified schematic of the Video Amplifier Output Stage including the blanking circuit Q18 serves as a buffer ...
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Circuit Description (Continued) age of Q29 There are also four diode drops from the base of Q30 to the output pin 20 Therefore during blanking pin 20 will be less than 100 mV above ground enabling the designer to blank ...
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... CRT driver stage separate from the resistors are ground of the LM1205 connecting the two grounds together only at one point National Semiconductor also manufac- tures a line of CRT drivers Please contact National for addi- tional information These drivers greatly simplify the driver ...
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Applications of the LM1205 FIGURE 16 Demonstration Board Layout (Continued 11831 – 20 ...
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Applications of the LM1205 FIGURE 17a Rise Time FIGURE 18 LM1205 Typical Application (Continued 11831 – 21 FIGURE 17b Fall Time 11831 – 11831– 23 ...
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... Italiano National does not assume any responsibility for use of any circuitry described no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications Order Number LM1205N NS Package Number N28B 2 A critical component is any component of a life ...