LM1246DKBNANOPB National Semiconductor, LM1246DKBNANOPB Datasheet
LM1246DKBNANOPB
Specifications of LM1246DKBNANOPB
Related parts for LM1246DKBNANOPB
LM1246DKBNANOPB Summary of contents
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... Enhanced I C compatible microcontroller interface to allow versatile Page RAM access © 2003 National Semiconductor Corporation n OSD Window Fade In/Fade Out n OSD Half Tone Transparency n Video Data dectection for Auto Centering & Sizing n OSD override allows OSD messages to override video and the use of burn-in screens with no video output ...
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Internal Block Diagram www.national.com FIGURE 1. Order Number LM1246AAA/NA See NS Package Number N24D 2 20068501 ...
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... Absolute Maximum Ratings 3) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage V , Pins 10 and 18 CC Peak Video DC Output Source Current (Any One Amp) Pins 19 Voltage at Any Input Pin ( Video Inputs (pk-pk) Thermal Resistance to Ambient (θ ...
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Video Signal Electrical Characteristics Unless otherwise noted 25˚ numbers refer to the definitions in Table 1. Test Settings. See (Note 7) for Min and Max parameters and (Note 6) for Typicals. Symbol Parameter Vid Video Threshold ...
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DAC Output Electrical Characteristics Unless otherwise noted 25˚ for Min and Max parameters and (Note 6) for Typicals. DAC parameters apply to all 4 DACs. Symbol Parameter V Min Output Voltage of DAC Min DAC V ...
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System Interface Signal Characteristics Unless otherwise noted 25˚ for Min and Max parameters and (Note 6) for Typicals. DAC parameters apply to all 4 DACs. Symbol Parameter V Minimum High Level Clamp CLAMP MIN Pulse Voltage ...
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Compatibility with LM1237 and LM1247 (Continued) The Compatibility of the LM1246 to the LM1237 and LM1253A is the same as that of the LM1247. Please refer to the LM1247 datasheet for details. LM1246 Pin: Assignment: OSD vs Video Intensity The ...
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Typical Performance Characteristics FIGURE 2. Logic Horizontal Blanking FIGURE 3. Logic Vertical Blanking FIGURE 4. Deflection Horizonal Blanking www.national.com 25˚C unless otherwise specified CC A 20068502 FIGURE 5. Deflection Vertical Blanking 20068503 FIGURE 6. Logic ...
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Typical Performance Characteristics SYSTEM INTERFACE SIGNALS The Horizontal and Vertical Blanking and the Clamping input signals are important for proper functionality of the LM1246. Both blanking inputs must be present for OSD synchroniza- tion. In addition, the Horizontal blanking input ...
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Typical Performance Characteristics PPL=0 PPL=1 PLL Auto 25 - 110 25 - 110 If 1152 pixels per line is being used, the horizontal scan rate would have to be lower than 106 kHz in order to not exceed the maximum ...
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Pin Descriptions and Application Information Pin Pin Name No REF 4 Analog Input Ground 5 Blue Video In 6 Red Video In 7 Green Video In 8 Digital Ground 10 PLL PLL Filter 11 SDA ...
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Pin Descriptions and Application Information Pin Pin Name No. 12 SCL 13 DAC 4 Output 14 DAC 2 Output 15 DAC 3 Output 16 DAC 1 Output 17 Ground Green Output 20 Red Output 21 Blue ...
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Pin Descriptions and Application Information Pin Pin Name No. 23 CLAMP 24 H Flyback (Continued) Schematic This pin accepts either TTL or CMOS logic levels. The internal switching threshold is approximately one-half of V series resistor avoid overdriving ...
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Schematic Diagram FIGURE 9. LM123x/LM124x-LM246x Demo Board Schematic www.national.com 14 20068524 ...
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Schematic Diagram FIGURE 10. LM123x/LM124x-LM246x Demo Board Schematic (continued) 15 20068525 www.national.com ...
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PCB Layout FIGURE 11. LM123x/LM124x-LM246x Demo Board Layout www.national.com 16 20068526 ...
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Programmable Horizontal Blank The leading edge position of the internal horizontal blank can be programmed with respect to the horizontal flyback zero crossing leading edge in steps of 4 OSD pixels maximum of 16 steps as shown ...
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Video Detection for Auto-Sizing & Auto-Centering OSD Generator Operation www.national.com FIGURE 13. Timing Intervals FIGURE 14. OSD Generator Block Diagram 18 (Continued) 20068553 20068527 ...
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OSD Generator Operation PAGE OPERATION Figure 14 shows the block diagram of the OSD generator. OSD screens are created using any of the 512 predefined characters stored in the mask programmed ROM. The LM1246 offers two modes of operation. The ...
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OSD Generator Operation WINDOWS Two separate windows can be opened, utilizing the data stored in the page RAM. Each window has its own horizontal and vertical start position, although the second window should be horizontally spaced at least two character ...
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OSD Generator Operation CHARACTER CELL Each character is defined column by 18 row matrix of picture elements, or “pixels”. The character font is shown in Figure 17 through Figure 24. There are two types of charac- ters ...
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OSD Generator Operation and background pixels in character two, Color 2: Those that are foreground pixels in character two and background pixels in character one, Color 3: Those that are foreground pixels for both characters. In order to identify which ...
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OSD Generator Operation parent’ or invisible. This allows the video information from the PC system to be visible on the screen when this is present. Note that this feature is enabled on any black color in any of the first ...
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OSD Generator Operation www.national.com (Continued) FIGURE 21. Button Box Detail FIGURE 22. On-Screen Effect of Button Boxes FIGURE 23. Shadowing 24 20068534 20068535 20068536 ...
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OSD Generator Operation Microcontroller Interface The microcontroller interfaces to the LM1246 preamp using 2 the I C compatible interface. The protocol of the interface begins with a Start Pulse followed by a byte comprised of a 7-bit Slave Device Address ...
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Microcontroller Interface LM1246 Address Map CHARACTER ROM The 512 font characters from 0x0000 to 0x7FFF can be read from ROM by addressing the individual pixel rows of the desired character. Since the characters have 12 columns, it takes two bytes ...
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LM1246 Address Map Address Range R/W 0x0000–0x2FFF R These are the first 3 banks of two-color, read-only ROM character fonts. There are 192 total characters in this range. 0x3000–0x3FFF R This is bank 3 of four-color, read-only ROM character fonts. ...
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LM1246 Address Map RAM Data Format (Standard LM1247 Mode) Each of the 512 locations in the page RAM is comprised of a 13-bit code consisting of an 8-bit character or control code, and a 4-bit attribute code. Each of the ...
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LM1246 Address Map Note that the pixels in the first line immediately below the character may be overwritten by the pixel override system that creates the button box. (Refer to the Button Box Formation Section for more information). After the ...
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... LM1246 Address Map Register Address Default COLWIDTH2B3 0x841F 0x00 Any registers in the range of 0x8420 - 0x8426 are for National Semiconductor internal use only and should not be written to under application conditions. BANKSEL_0–1 0x8427 0x10 BANKSEL_2–3 0x8428 0x32 FADE_INTVL 0x8429 0x35 PREAMPLIFIER CONTROL These registers, shown in Table 14 ...
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LM1246 Address Map When reading read only one, two, or all three bytes. When writing more than one 2-color attribute using the auto increment feature, all four bytes must be written. When writing, bytes 0 through ...
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Building Display Pages always contain the Skip-Line (SL) code associated with the first line of Display Window 1. The attribute for this SL code must be written before the SL code itself, and will be stored in the lower four ...
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Building Display Pages X HALF RANDOM ADDRESS MODE The Half Random Address mode allows different attribute and character codes to be sent within one transmission in the same way as the Two Byte Communication mode. The entire 512-character Page ROM ...
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Control Register Definitions Bit 0 On-Screen Display Enable. The On-Screen Display will be disabled when this bit is a zero. When this bit is a one the On-Screen Display will be enabled. This controls both Window 1 and Window 2. ...
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Control Register Definitions Bits 7–2 Reserved. These should be set to zero. Vertical Blank Duration Register: Res’d X Bits 6–0 This register determines the duration of the vertical blanking signal in scan lines. When vertical blanking is enabled ...
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Control Register Definitions Bit 0 This controls the calculation of the ROM signature. Setting this bit causes the ROM to be read sequentially and a 16-bit checksum calculated over the 256 characters. The sum, modulo 65535, is stored in the ...
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Control Register Definitions COLWIDTH1B1 (0x8415) Bits 31–0 These are the Display Window 1 Column Width 2x Enable Bits. These thirty-two bits correspond to columns 31–0 of Display Window 1, respectively. A value of zero indicates the column will have normal ...
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Control Register Definitions Bits 31–0 These are the Display Window 2 Column Width 2x Enable Bits. These thirty-two bits correspond to columns 31–0 of Display Window 2, respectively. A value of zero indicates the column will have normal width (12 ...
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Control Register Definitions 2. Then, the 3-bit address obtained from B0AD[2:0], B1AD[2:0], B2AD[2:0] and B3AD[2:0] are used to select four of the eight color ROM banks as shown in Table 29. Resulting ROM Bank Address. The BxAD[2:0] ...
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Pre-Amplifier Interface Registers Bits 6–0 This register determines the gain of the red video channel. This affects only the red channel whereas the contrast register (0x8433) affects all channels. Bit 7 Reserved and should be set to zero. Contrast Control: ...
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Pre-Amplifier Interface Registers Bit 5 When this bit the full-scale outputs of DACs 1–3 are 0.5V to 4.5V. When the full-scale level is 0.5V to 2.5V. Bit 6 When this bit is a ...
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Pre-Amplifier Interface Registers Bit 7 Reserved and should be set to zero. Software Reset and Test Control: Res’d X Bit 0 When this bit all registers except this one are loaded with their default values. All operations ...
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Pre-Amplifier Interface Registers Horizontal Front Porch Duration: H_FP1 (0x8581) Reserved Bit 10–0 This is an 11-bit wide register that records the lowest measured value of the horizontal front porch during video detect. When no video ...
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Pre-Amplifier Interface Registers Bits 7–0 This is an 8-bit wide register that records the measured value of the vertical flyback or sync in terms of horizontal line periods during video detect. Once measurement is completed and the auto size enable ...
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Attribute Table and Enhanced Features TABLE 30. Enhanced Feature Descriptions (Continued) Bits 21–18 0100b 0101b 0110b 0111b 1000b 1001b 1010b 1011b 1100b 1101b 1110b 1111b FOUR COLOR ATTRIBUTE FORMAT The address range for an attribute number, 0 ≤ n ≤ ...
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Attribute Table and Enhanced Features TABLE 31. Attribute Tables and Corresponding Addresses (Continued) Attribute Number, n Two-Color Attribute Table Address 0011b 0100b 0101b 0110b 0111b 1000b 1001b 1010b 1011b 1100b 1101b 1110b 1111B BUTTON BOX FORMATION The value of the ...
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Attribute Table and Enhanced Features (Continued) all pixels surrounding the pixel. When a black override output is 1 for a given pixel position, X, the color of that pixel changed to the color code stored in the register EF3. Because ...
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Attribute Table and Enhanced Features FIGURE 31. ROM Bank 3 Four Color Character Font www.national.com (Continued) FIGURE 29. ROM Bank 1 Two Color Character Font FIGURE 30. ROM Bank 2 Two Color Character Font 48 20068545 20068546 20068547 ...
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Attribute Table and Enhanced Features FIGURE 32. ROM Bank 4 Two Color Character Font FIGURE 33. ROM Bank 5 Two Color Character Font FIGURE 34. ROM Bank 6 Two Color Character Font (Continued) 49 20068548 20068549 20068550 www.national.com ...
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Attribute Table and Enhanced Features FIGURE 35. ROM Bank 7 Four Color Character Font www.national.com (Continued) 50 20068551 ...
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... BANNED SUBSTANCE COMPLIANCE National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ‘‘Banned Substances’’ as defined in CSP-9-111S2. ...