LM1237BDKD/NA/NOPB National Semiconductor, LM1237BDKD/NA/NOPB Datasheet
LM1237BDKD/NA/NOPB
Specifications of LM1237BDKD/NA/NOPB
Related parts for LM1237BDKD/NA/NOPB
LM1237BDKD/NA/NOPB Summary of contents
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... Features compatible microcontroller interface Block and Connection Diagram © 2004 National Semiconductor Corporation n Internal 254 character OSD usable as either (a) 190 2-color plus 64 4-color characters, (b) 318 2-color characters, or (c) some combination in between. n OSD override allows OSD messages to override video and the use of burn-in screens with no video input ...
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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 15 and 19 Peak Video DC Output Source Current (Any One Amp) Pins 18 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. See Note 7 for Min and Max parameters and Note 6 for Typicals. Symbol Parameter V TH ABL Control Range ...
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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 Note 2: Limits of operating ratings indicate required boundaries of conditions for which the device is functional, but may not meet specific performance limits. Note 3: All voltages are measured with respect to GND, unless otherwise ...
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LM1253A Compatibility In order to maintain register compatibility with the LM1253A preamplifier datasheet assignments for bias and brightness, the color assignments are recommended as shown in Table 2. If datasheet compatibility is not required, then the DAC assignments can be ...
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Typical Performance Characteristics Figure 4 and Figure 5 show the case where the horizontal and vertical inputs are from deflection. Figure 4 shows the pin 24 voltage which is derived from a horizontal flyback pulse of 35 volts peak to ...
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Typical Performance Characteristics ABL Gain Reduction The ABL function reduces the contrast level of the LM1237 as the voltage on pin 22 is lowered from V 8 shows the amount of gain reduction as the voltage is lowered from V ...
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Pin Descriptions and Application Information Pin Pin Name No Flyback 2 V Bypass REF 3 V Current Set REF 4 Analog Ground 5 Blue Video In 6 Red Video In 7 Green Video In 8 Digital Ground 10 ...
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Pin Descriptions and Application Information Pin Pin Name No. 9 PLL Filter 11 SDA 12 SCL 13 DAC 4 Output 14 DAC 2 Output 15 DAC 3 Output 16 DAC 1 Output 17 Ground Green Output ...
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Pin Descriptions and Application Information Pin Pin Name No. 22 ABL 23 CLAMP 24 H Flyback (Continued) Schematic The Automatic Beam Limiter input is biased to the desired beam current limit by R and normally keeps D the current resupplying ...
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Schematic Diagram www.national.com FIGURE 9. LM123x-LM246x Demo Board Schematic 12 20023416 ...
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Schematic Diagram FIGURE 10. LM123x-LM246x Demo Board Schematic (continued) 13 20023417 www.national.com ...
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PCB Layout www.national.com FIGURE 11. LM123x-LM246x Demo Board Layout 14 20023418 ...
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OSD Generator Operation PAGE OPERATION Figure 12. shows the block diagram of the OSD generator. FIGURE 12. Block Diagram of the OSD Generator Video information is created using any of the 256 predefined characters stored in the mask programmed ROM. ...
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OSD Generator Operation OSD VIDEO TIMING The OSD SELECT signal switches the source of video infor- mation within the preamplifier from external video to the internally generated OSD video. WINDOWS Two separate windows can be opened, utilizing the data stored ...
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OSD Generator Operation 18 rows Plane 1 + 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 12 bits ...
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OSD Generator Operation ENHANCED FEATURES In addition to the wide selection of colors for each character, additional character features can be selected on a character by character basis. There are 3 Enhanced Feature Regis- ters, EF0, EF1 and EF2. 1. ...
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OSD Generator Operation Microcontroller Interface The microcontroller interfaces to the LM1237 preamp via the compatible interface. The protocol of the interface begins with a Start Pulse followed by a byte comprised of a seven bit Slave Device ...
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Microcontroller Interface READ SEQUENCE Read sequences are comprised of two I fer sequences: The first is a write sequence that only trans- fers the two byte address to be accessed. The second is a read sequence that starts at the ...
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LM1237 Address Map Address Range R/W 0x0000–0x2FFF R 0x3000–0x3FFF R 0x4000–0x7FFF — Address Range R/W 0x8000–0x81FF R/W Preamp Interface Registers Register Address Default 0x0000– Fonts - 2 Color 0x2FFE +1 0x3000– Fonts - 4 Color 0x3FFE +1 0x8000– Display Page ...
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Preamp Interface Registers Register Address Default CHARHTCTRL 0x8404 0x51 BBHLCTRLB0 0x8405 0xFF BBHLCTRLB1 0x8406 0x01 BBLLCTRLB0 0x8407 0x00 BBLLCTRLB1 0x8408 0x00 CHSDWCTRLB0 0x8409 0x00 CHSDWCTRLB1 0x840A 0x00 ROMSIGCTRL 0x840D 0x00 ROMSIGDATAB0 0x840E 0x00 ROMSIGDATAB1 0x840F 0x00 HSTRT1 0x8410 0x13 VSTRT1 ...
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Two-Color Attribute Table TABLE 8. LM1237 Two-Color Attribute Registers (Continued) Register Address D7 ATT2C1n +1 C2B[0] ATT2C2n +2 X ATT2C3n +3 X Note: Set reserved bits to 0. The attributes for two-color display characters may be written or read via ...
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Display Page RAM (Continued) Bits 11–4 (Character Code): These 8 bits define which of the 254 characters called from the character ROM. Valid character codes are 0x02–0xFF. Bits 3–0 (Attribute Code): These 4 bits address the attribute ...
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Display Page RAM (Continued) The WE control code tells the OSD generator that the character codes following belong to another displayed window at the next window location control code may follow normal characters parameter, but ...
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Display Page RAM (Continued) • The colors of the characters and background can be stored in a single location in the 2-color attribute table, in location ATT0. • The data shown in Table 10. Example 1 Data Transmission is sent ...
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Display Page RAM (Continued) Notes: • Every row must begin with an attribute and an SL value. Display Page RAM memory location 0x8000 will always be associated with the SL of row 0 of Display Window # 1. 2 • ...
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Display Page RAM (Continued) Data Sent 0x05 Character “D” 0x06 Character “E” 0x07 Character “F” 0x01 Row-End (RE) Command stop condition (See the Microcontroller Interface Section start condition (See the Microcontroller Interface Section) 0xBA ...
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Display Page RAM (Continued) Notes: • In order to centralize the three characters above the five characters on the row below, a “transparent” blank character has been used as the first character on the row. • In order to create ...
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Display Page RAM (Continued) Data Sent 0xBA Chip address (See the Microcontroller Interface Section) 0x06 Address LSB 0x80 Address MSB 0x00 Use Attribute table 0x00 for the following character 0x03 Skip 3 lines Command 0x01 Row-End (RE) Command 2 I ...
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Control Register Definitions Frame Control Register 2 Register Name (address): FRMCTRL2 (0x8401) Bits 4–0 Blinking Period. These five bits set the blinking period of the blinking feature, which is determined by mulitiplying the value of these bits by 8, and ...
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Control Register Definitions Character Font Access Register Register Name (address): CHARFONTACC (0x8402) 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 ...
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Control Register Definitions Character Height Register Register Name (address): CHARHTCTRL (0x8404) Bits 7–0 This register determines the OSD character height as described in the section Constant Character Height Mechanism. The values of this register is equal to the approximate number ...
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Control Register Definitions Register Names (addresses): ROMSIGDATAB1 (0x840F) and ROMSIGDATAB0 (0x840E CRC15 CRC14 CRC13 CRC12 CRC11 CRC10 CRC9 CRC8 CRC7 CRC6 CRC5 CRC4 CRC3 CRC2 CRC1 CRC0 Bits 15–0 This is the checksum of the ...
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Control Register Definitions Display Window 1 Column Width Register Register Names (addresses): COLWIDTH1B3 COLWIDTH1B0 (0x8414 COL COL COL COL COL COL15 COL14 COL13 COL12 COL11 ...
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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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Pre-Amplifier Interface Registers Bits 7–0 This register determines the output of DAC 2. The full-scale output is determined by bit 5 of the DAC Config, OSD Contrast & DC Offset Register. DAC 3 REGISTER Register Name (address): DAC3CTRL (0x8436) 7 ...
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Pre-Amplifier Interface Registers Bit 3 This is the OSD override bit. This should be set to 0 for normal operation. When set the video outputs are disconnected and OSD only is displayed. This is useful for the ...
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Attribute Table and Enhanced Features TABLE 13. Enhanced Feature Descriptions (Continued) Bits 21–18 0011b Bordering 0100b RESERVED 0101b RESERVED 0110b RESERVED 0111b RESERVED 1000b Raised Box 1001b Blinking and Raised Box 1010b Depressed Box 1011b Blinking and Depressed Box 1100b ...
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Attribute Table and Enhanced Features TABLE 14. Attribute Tables and Corresponding Addresses (Continued) Attribute Value (n) Two-Color Attribute Table Address 1001b 1010b 1011b 1100b 1101b 1110b 1111b BUTTON BOX FORMATION The value of the most significant Enhanced Feature Bit (EFB3) ...
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Attribute Table and Enhanced Features (Continued) Operation of the Bordering Feature Borders are created in a similar manner to the shadows, using the pixel override system to overwrite pixel data with a pixel color set by EF3. However, instead of ...
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