LM1236 National Semiconductor Corporation, LM1236 Datasheet
LM1236
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LM1236 Summary of contents
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... DAC outputs, which are well matched to the LM2479 and LM2480 integrated bias clamp ICs. The LM1236 preamp is also designed to be compatible with the LM246x high gain driver family. Black level clamping of the video signal is carried out directly ...
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... Internal Block Diagram www.national.com FIGURE 1. Order Number LM1236AAA/NA See NS Package Number N24D 2 20075701 ...
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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 V , Pins 10 and 18 CC Peak Video DC Output Source Current (Any One Amp) Pins ...
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Video Signal Electrical Characteristics Unless otherwise noted 25˚ numbers refer to the definitions in Table 1 . See (Note 7) for Min and Max parameters and (Note 6) for Typicals. Symbol Parameter V TH ABL Control ...
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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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... Note 15: A minimum pulse width of 200 ns is the guaranteed minimum for a horizontal line of 15 kHz. This limit is guaranteed by design lower line rate is used then a longer clamp pulse may be required. Note 16: Adjust input frequency from 10 MHz (A Note 17: Once the spot killer has been activated, the LM1236 remains in the off state until V Hexadecimal and Binary Notation Hexadecimal numbers appear frequently throughout this document, representing slave and register addresses, and register values. These appear in the format “ ...
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... OSD intensity to the most pleasing level. ESD Protection The LM1236 features a 3.0 kV ESD protection level (see (Notes 4, 13)). This is provided by special internal circuitry which activates when the voltage at any pin goes beyond the supply rails by a preset amount. At that time, the protection is applied to all the pins, including SDA and SCL ...
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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 20075702 FIGURE 5. Deflection Vertical Blanking 20075703 FIGURE 6. Logic ...
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... The PLL in the LM1236 has a maximum pixels per line setting significantly higher than that of the LM1247. The range for the LM1236 is from 704 to 1152 pixels per line, in increments of 64. The maximum OSD pixel frequency avail- able is 111 MHz. For example, if the horizontal scan rate is ...
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... OSD pixel frequency of 111 MHz. The maxi- mum number of vertical video lines that may be used is 1536 lines 2048x1536 display. The LM1236 has a PLL Auto feature, which will automatically select an internal PLL frequency range setting that will guarantee optimal OSD locking for any horizontal scan rate ...
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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 Digital 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 20075724 ...
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Schematic Diagram FIGURE 10. LM123x/LM124x-LM246x Demo Board Schematic (continued) 15 20075725 www.national.com ...
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PCB Layout FIGURE 11. LM123x/LM124x-LM246x Demo Board Layout www.national.com 16 20075726 ...
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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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OSD Generator Operation PAGE OPERATION Figure 13 shows the block diagram of the OSD generator. OSD screens are created using any of the 256 predefined characters stored in the mask programmed ROM. Each character has a unique 8-bit code that ...
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OSD Generator Operation OSD VIDEO TIMING The OSD analog signal then goes to the switch, shown in Figure 14 and Figure 1 where the timing control switches from input video to OSD and back again as determined by CHARACTER CELL ...
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OSD Generator Operation FOUR COLOR FONT AS TWO 2-COLOR Using a 4 color character as two 2 color characters is achieved by careful assignment of the four colors. When two 2 color characters are combined, there will be four pixel ...
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OSD Generator Operation FIGURE 18. Displaying Each Character Individually ATTRIBUTE TABLES Each character has an attribute value assigned the page RAM. The attribute value is 4 bits wide, making each character entry in the page RAM 13 ...
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OSD Generator Operation OSD WINDOW FADE IN/ FADE OUT The OSD window can be opened and closed with a fade in/fade out effect. The interval for fading in and fading out the OSD window in the horizontal and vertical direction ...
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OSD Generator Operation FIGURE 20. On-Screen Effect of Button Boxes (Continued) FIGURE 19. Button Box Detail 20075736 FIGURE 21. Shadowing 23 20075734 20075735 www.national.com ...
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... LM1236 preamp associated with the ad- dress indicated by the two address bytes. Subsequent read data bytes will correspond to the next increment address locations. Data should only be read from the LM1236 when both OSD windows and the Fade In/ Fade Out are disabled. 24 ...
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... Microcontroller Interface LM1236 Address Map CHARACTER ROM Note that bit 0 of the Character Font Access Register, 0x8402, needs to be set read the 2-color fonts. In order to read the four-color fonts, two complete reads are needed. Set bit 0 of the Character Font Access Register, 0x8402 read the least significant plane and read the most significant plane ...
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... LM1236 Address Map Address Range 0x0000–0x2FFF 0x3000–0x3FFF 0x4000–0x7FFF DISPLAY PAGE RAM This address range (0x8000–0x81FF) contains the 512 characters, which comprise the displayable OSD screens. There must be at least one End-Of-Screen code (0x00) in this range to prevent unpredictable behavior. NOTE: To avoid any unpredictable behavior, this range should be cleared by writing bit 3 of the FRMCTRL1 Register, 0x8400, immediately after power up ...
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... LM1236 Address Map are used, one for 2-color characters, the other for 4-color characters. Each of the characters are stored in sequence in the Page RAM. Special codes are used between lines to show where oneline ends and the next begins, and also to allow blank (or ’ ...
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... TABLE 11. OSD Control Register Detail (Continued B[1: B[1: V_INTVL[3:0] TABLE 12. LM1236 Preamplifier Interface Registers DCF[1: HB_POS[3:0] PLL_ X CLMP AUTO X AID ...
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... ATT4C4n +4 ATT4C5n +5 ATT4C6n +6 ATT4C7n +7 (Continued) Address = 0x8440 + (N * 0x4 where Attribute number (0x0 ≤ N ≤ 0xF Attribute byte number (0x0 ≤ B ≤ 0x3) TABLE 13. LM1236 Two-Color Attribute Registers C0B[1:0] C1B[0] C1G[2: Address = 0x8500 + (N * 0x8 where Attribute number (0x0 ≤ N ≤ 0xF Attribute byte number (0x0 ≤ ...
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... ENHANCED PAGE RAM ADDRESS MODES Since the Page RAM in the LM1236 is 12 bits wide, usually two bytes of Page RAM information has to be sent to every location. To avoid this, the LM1236 addressing control system has 3 additional addressing modes offering increased flexibility that may be helpful in sending data to the Page RAM. Some of the left over bits in the Attribute byte are employed as data control bits to select the desired addressing mode as shown in Table 16 . This is identified as the first byte sent in a write operation or the Page RAM’ ...
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Building Display Pages X When bits 6–5 are 0, the 4-bit attribute code will be automatically applied to all the character codes transmitted after this attribute byte the LM1237 and LM1247. This mode is useful for sending character ...
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Building Display Pages Control Register Definitions OSD INTERFACE REGISTERS Frame Control Register 1: halftone HTD 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 ...
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Control Register Definitions Character Font Access Register: X Bit 0 This is the Color Bit Plane Selector. This bit must be set read or write a two-color attribute from the range 0x0000 to 0x2FFF. When reading or ...
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Control Register Definitions CHSDWCTRLB1 (0x840A) Reserved Bits 8–0 These registers determine the heavy button box lowlight, shading or shadow color. Bits 15–9 Reserved. These bits should be set to zero. ROM Signature Control Register: X ...
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... SL code for the first line of Display Window 1. This register is new for the LM1236 and allows Window 1 to start anywhere in the Page RAM rather than just at 0x8000. Note that the address this points to in Page RAM must always contain the SL code for the first line of the window. Bits 15– ...
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Control Register Definitions Bits 15–9 These bits are reserved and should be set to zero. Display Window 2 Column Width: COLWIDTH2B3 (0x841F) COLWIDTH2B1 (0x841D) Bits 31–0 These are the Display Window 2 Column Width 2x Enable Bits. These thirty-two bits ...
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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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... Bit 4 Reserved and should be set to zero. Bit 5 This is the Clamp Polarity bit. When set the LM1236 expects a positive going clamp pulse. When set the expected pulse is negative going. Bit 6 When this bit is set, the PLL Auto Mode will automatically determine the optimum frequency range of the Phase Locked Loop ...
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Pre-Amplifier Interface Registers Software Reset and Test Control: Res’d X AID Bit 0 When this bit all registers except this one are loaded with their default values. All operations are aborted, except data transfers in progress on ...
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Attribute Table and Enhanced Features TABLE 25. Enhanced Feature Descriptions (Continued) Bits 21–18 1100b 1101b 1110b 1111b FOUR COLOR ATTRIBUTE FORMAT The address range for an attribute number, 0 ≤ n ≤ 15, is provided in Table 26 . ATT4C7n ...
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Attribute Table and Enhanced Features (Continued) BUTTON BOX FORMATION The value of the most significant Enhanced Feature Bit (EFB3) determines when to draw the left, right, bottom and top sides of a Box. EFB1 denotes whether a box is raised ...
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... Attribute Table and Enhanced Features (Continued) Evaluation Character Fonts The character font for evaluation of the LM1236 is shown in Figure 26 . The actual font will depend on customer customi- zation requirements. www.national.com FIGURE 26. ROM Character Font 42 20075744 ...
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... English www.national.com Français Tel: +33 ( 8790 24-Lead DIP Molded Plastic Package Order Number LM1236AAA/NA NS Package Number N24D 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 ...