lm2450 National Semiconductor Corporation, lm2450 Datasheet
lm2450
Related parts for lm2450
lm2450 Summary of contents
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... Monolithic Triple Channel 7 MHz DC Coupled CRT DTV Driver General Description The LM2450 is a triple channel high voltage DC coupled CRT driver circuit designed for use in DTV applications. The IC contains three high input impedance, wide band amplifi- ers which directly drive the RGB cathodes of a CRT. Each amplifier has a summing input where the DC level of the output is controlled by a low voltage DC input voltage ...
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... Note 7: Running the 1 MHz to 30 MHz test pattern at 1080i this part will dissipate approximately 9.2 W. This is the commonly accepted test pattern that is representative of the worst case high frequency content for normal television viewing. This is the pattern used to estimate the worst case power dissipation of the LM2450 in its normal application recommended to use a heat sink with a thermal resistance of 5.4˚C/W or better. www.national.com ...
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... Note load includes parasitic capacitance. Figure 3 shows a typical test circuit for evaluation of the LM2450. This circuit is designed to allow testing of the LM2450 in a 50Ω environment without the use of an expensive FET probe. The two 4990Ω resistors form a 400:1 divider with the 50Ω resistor and the oscilloscope ...
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... Typical Performance Characteristics (60V – 190V 50˚C, Test Circuit — Figure 3 unless otherwise specified) C FIGURE OUT FIGURE 5. LM2450 Pulse Response FIGURE 6. Bandwidth www.national.com (V = +220V , 20144304 FIGURE 7. Speed vs Load Capacitance IN 20144305 20144306 FIGURE 9. Speed vs Case Temperature 4 = +12V , pF, V ...
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... Typical Performance Characteristics (60V – 190V 50˚C, Test Circuit — Figure 3 unless otherwise specified) C FIGURE 10. Power Dissipation vs Frequency (V = +220V , 20144310 FIGURE 11. Safe Operating Area 20144312 FIGURE 12. LM2450 Cathode Response 5 = +12V , pF 130V OUT 20144311 www.national.com PP ...
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... The part is housed in a 15-lead TO-247 molded plastic power package with thin leads for improved metal-to-metal spacing. The circuit diagram of the LM2450 is shown in Figure 2 . The PNP emitter follower, Q5, provides input buffering. Q1 and Q2 form a fixed gain cascode amplifier with resistors R1 and R2 setting the gain at − ...
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... LM2450. One test MHz sine wave sweep over the active line. This would give a slightly lower power than taking the average of the power between 1 and 30 MHz. ...
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... CURRENT OUTPUT FOR IK FEEDBACK SYSTEMS The LM2450 can be used in DTV applications that use an IK feedback system. Figure 14 shows an example of an inter- face circuit used to feed back the IK output of LM2450 to a preamplifier with an ac coupled IK input. www.national.com This feedback system consists of the preamp, LM2450, and ...
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... Application Hints (Continued) FIGURE 15. LM2450 DTV Demonstration Board Layout www.national.com 10 20144316 ...
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Application Hints (Continued) FIGURE 16. Trace Routing and Component Placement for Blue Channel Output 20144317 11 www.national.com ...
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... English www.national.com Français Tel: +33 ( 8790 NS Package Number TB15A Order Number LM2450TB 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system affect its safety or effectiveness. ...