VP5311C

Obsolescence Notice This product is obsolete. This information is available for your convenience only. For more information on Zarlink’s obsolete products and replacement product lists, please visit http://products.zarlink.com/obsolete_products/ VP5311C/VP5511C NTSC/PAL Digital Video Encoder Supersedes May 1997 edition DS4575 - 1.0 DS4773 - 2.3 March 1998 The VP5311C/VP5511C converts digital Y, Cr, Cb, data into analog NTSC/PAL composite video and S-video signals. The outputs are capable of driving doubly terminated 75 ohm loads with standard video levels. The device accepts data inputs complying with CCIR Recommendation 601 and 656. The data is time multiplexed on an 8 bit bus at 27MHz and is formatted as Cb, Y, Cr, Y (i.e. 4:2:2). The video blanking and sync information from REC 656 is included in the data stream when the VP5311C/ VP5511C is working in slave mode. The output pixel rate is 27MHz and the input pixel rate is half this frequency, i.e. 13.5MHz. All necessary synchronisation signals are generated internally when the device is operating in master mode. In slave mode the device will lock to the TRS codes or the HS and VS inputs. The rise and fall times of sync, burst envelope and video blanking are internally controlled to be within composite video specifications. Three digital to analog converters (DACs) are used to convert the digital luminance, chrominance and composite data into true analog signals. An internally generated reference voltage provides the biasing for the DACs. PIN 1 IDENT PIN 52 PIN 1 GP52 Fig.1 Pin connections (top view) PIN 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 FUNCTION D0 (VS I/O) D1 (HS I/O) D2 (FC0 O/P) D3 (FC1 O/P) D4 (FC2 O/P) D5 D6 (SCSYNC I/P) D7 (PALID I/P) GND VDD GND PXCK VDD CLAMP COMPSYNC TDO TDI TMS TCK GND SA1 SA2 SCL VDD SDA VDD PIN 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 FUNCTION RESET REFSQ GND PD7 PD6 PD5 PD4 PD3 PD2 PD1 PD0 GND VDD AGND VREF DACGAIN COMP AVDD LUMAOUT AGND COMPOUT AGND CHROMAOUT AVDD AVDD AVDD FEATURES s Converts Y, Cr, Cb data to analog composite video and S-video s Supports CCIR recommendations 601 and 656 s All digital video encoding s Selectable master/slave mode for sync signals s Switchable chrominance and luma bandwidth s Switchable pedestal with gain compensation s SMPTE 170M NTSC or CCIR 624 PAL compatible outputs s GENLOCK mode s Line 21 Closed Caption encoding s I2C bus serial microprocessor interface s VP5311C supports Macrovision V7.01anti-taping format APPLICATIONS s s s s s s Digital Cable TV Digital Satellite TV Multi-media Video games Karaoke Digital VCRs ORDERING INFORMATION VP5311C/CG/GP1N VP5511C/CG/GP1N VP5311C/VP5511C ELECTRICAL CHARACTERISTICS Test conditions (unless otherwise stated): As specified in Recommended Operating Conditions DC CHARACTERISTICS Parameter Digital Inputs TTL compatible (except SDA, SCL) Input high voltage Input low voltage Digital Inputs SDA, SCL Input high voltage Input low voltage Input high current Input low current Digital Outputs CMOS compatible Output high voltage Output low voltage Digital Output SDA Output low voltage VIN = VDD VIN = VSS IOH = -1mA IOL = +4mA IOL = +6mA Conditions Symbol VIH VIL VIH VIL IIH IIL VOH VOL VOL 3.7 0.4 0.6 Min. 2.0 0.8 0.7 VDD 0.3 VDD 10 -10 Typ. Max. Units V V V V µA µA V V V ELECTRICAL CHARACTERISTICS Test conditions (unless otherwise stated): As specified in Recommended Operating Conditions DC CHARACTERISTICS DACs Parameter Accuracy (each DAC) Integral linearity error Diffential linearity error DAC matching error Monotonicity LSB size Internal reference voltage Internal reference voltage output impedance Reference Current (VREF/RREF) RREF = 769Ω DAC Gain Factor (VOUT = KDAC x IREF x RL), VOUT = DAC code 511 Peak Glitch Energy (see fig.3) CVBS, Y and C - NTSC (pedestal enabled) Maximum output, relative to sync bottom White level relative to black level Black level relative to blank level Blank level relative to sync level Colour burst peak - peak DC offset (bottom sync) CVBS, Y and C - PAL Maximum output White level relative to black level White level relative to sync level Black level relative to sync level Colour burst peak - peak DC offset (bottom sync) Symbol INL DNL guaranteed Min. Typ. Max. ±1.5 ±1 ±5 Units LSB LSB % µA V Ω mA pV-s VREF ZR IREF KDAC 66.83 1.050 27k 1.3699 24.93 50 33.75 17.64 1.40 7.62 7.62 0.40 mA mA mA mA mA mA 34.15 18.71 26.73 8.02 8.02 0.00 mA mA mA mA mA mA Note: All figures are for: RREF = 769Ω RL = 37.5Ω. When the device is set up in NTSC mode there is a +0.25% error in the PAL levels. If RL = 75Ω then RREF = 1538Ω. ABSOLUTE MAXIMUM RATINGS Supply voltage VDD, AVDD Voltage on any non power pin Ambient operating temperature Storage temperature -0·3 to 7·0V -0·3 to VDD+0·3V 0 to 70°C -55°C to 150°C Note: Stresses exceeding these listed under Absolute Maximum Ratings may induce failure. Exposure to Absolute Maximum Ratings for extended periods may reduce reliability. Functionality at or above these conditions is not implied. 2 VP5311C/VP5511C RECOMMENDED OPERATING CONDITIONS Parameter Power supply voltage Power supply current (including analog outputs) Input clock frequency SCL clock frequency Analog video output load DAC gain resistor Ambient operating temperature Symbol Min. Typ. Max. Units V mA MHz kHz Ω Ω °C VDD, AVDD 4.75 IDD PXCK -50ppm fSCL 0 5.25 5.00 150 27.00 +50ppm 500 37.5 769 70 VIDEO CHARACTERISTICS Parameter Luminance bandwidth (high) Luminance bandwidth (medium) Luminance bandwidth (low) Chrominance bandwidth (Extended B/W mode) Chrominance bandwidth (Reduced B/W mode) Burst frequency (NTSC) Burst frequency (PAL-B, D,G,H,I) Burst frequency (PAL-M) Burst frequency (PAL-N Argentina) Burst cycles (NTSC and PAL-M,N) Burst cycles (PAL-B, D, G, H,I) Burst envelope rise / fall time (all standards) Analog video sync rise / fall time (NTSC and PAL-M,N) Analog video sync rise / fall time (PAL-B, D, G, H,I) Differential gain Differential phase Signal to noise ratio (unmodulated ramp) Chroma AM signal to noise ratio (100% red field) Chroma PM signal to noise ratio (100% red field) Hue accuracy Colour saturation accuracy Residual sub carrier Luminance / chrominance delay Symbol Min. Typ. 6.16 4.34 2.79 1.3 650 3.57954545 4.43361875 3.57561189 3.58205625 9 10 300 145 245 1.0 0.5 -61 -56 -58 2.5 2.5 -5 -60 0 +5 Max. Units MHz MHz MHz MHz kHz MHz MHz MHz MHz Fsc cycles Fsc cycles ns ns ns % pk-pk ° pk-pk dB dB dB % % dB ns ESD COMPLIANCE Pins All pins All pins Test Human body model Machine model Test Levels 2kV on 100pF through 1k5Ω 200V on 200pF through 0Ω & 500nH Notes Meets Mil-Std-883 Class 2 3 VP5311C/VP5511C SDA SCL SA1 SA2 RESET VIDEO TIMING GENERATOR I2C INTERFACE SET-UP REGISTERS ANTI-TAPING CONTROL CLOSED CAPTION CLAMP + + + Y INPUT DEMUX & Cr SYNC BLANK INSERT INTERPOLATOR COMPSYNC LUMA OUT LUMA DAC 8 COMP DAC COMP OUT PD7-0 CHROMA INTERP Cb PXCK 8 D7-0 GENERAL PURPOSE PORT CHROMA LOW -PASS FILTER INTERPOLATOR MODULATOR CHROMA DAC CHROMA OUT DIGITAL PHASE COMP COLOUR SUBCARRIER GENERATOR TDI JTAG. TDO TMS TCK DAC REF DACREF VREF REFSQ COMP Fig.2 Functional block diagram of the VP5311C, the VP5511C is identical except there is no Anti-Taping Control V W H Peak Glitch Area = H x W/2 t(ps) The glitch energy is calculated by measuring the area under the voltage time curve for any LSB step, typically specified in picoVolt-seconds (pV-s) Fig.3 Glitch Energy 4 VP5311C/VP5511C PIN DESCRIPTIONS Pin Name PD7-0 D0-7 PXCK CLAMP Pin No. 30 - 37 1-8 12 14 Description 8 Bit Pixel Data inputs clocked by PXCK. PD0 is the least significant bit, corresponding to Pin 37. These pins are internally pulled low. 8 Bit General Purpose Port input/output. D0 is the least significant bit, corresponding to Pin 1. These pins are internally pulled low. 27MHz Pixel Clock input. The VP5311C/5511C internally divides PXCK by two to provide the pixel clock. The CLAMP output signal is synchronised to COMPSYNC output and indicates the position of the BURST pulse, (lines 10-263 and 273-525 for NTSC and PAL-M; lines 6-310 and 319-623 for PAL-B,D, G,I,N(Argentina)). Composite sync pulse output. This is an active low output signal. JTAG Data output port. JTAG Data input port. JTAG mode select input. JTAG clock input. I2C slave address select I2C slave address select. Standard I2C bus serial clock input. Standard I2C bus serial data input/output. Master reset. This is an asynchronous, active low, input signal and must be asserted for a minimum 200ns in order to reset the VP5311C/5511C. Reference square wave input used only during Genlock mode. Voltage reference input/output. This pin is nominally 1.055V and should be decoupled with a 100nF capacitor to GND. DAC full scale current control. A resistor connected between this pin and GND sets the magnitude of the video output current. An internal loop amplifier controls a reference current flowing through this resistor so that the voltage across it is equal to the Vref voltage. DAC compensation. A 100nF ceramic capacitor must be connected between pin 43 and pin 44. True luminance, composite and chrominance video signal outputs. These are high impedance current source outputs. A DC path to GND must exist from each of these pins. COMPSYNC TDO TDI TMS TCK SA1 SA2 SCL SDA RESET REFSQ VREF DAC GAIN 15 16 17 18 19 21 22 23 25 27 28 41 42 COMP LUMAOUT COMPOUT CHROMAOUT VDD AVDD GND AGND 43 45 47 49 10, 13, 24, Positive supply input. All VDD pins must be connected. 26, 39 44, 50, 51, 52 9, 11, 20, 29, 38 40, 46, 48 Negative supply input. All AGND pins must be connected. Negative supply input. All GND pins must be connected. Analog positive supply input. All AVDD pins must be connected. 5 VP5311C/VP5511C REGISTERS MAP See Register Details for further explanations. ADDRESS REGISTER NAME hex BAR 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E to 1F 20 21 22 23-33 34 to EF F0 F1 F2 F3 F4 F5 to F7 F8 F9 FA FB FC FD FE FF PART ID2 PART ID1 PART ID0 REV ID GCR VOCR HANC ANCID SC_ADJ FREQ2 FREQ1 FREQ0 SCHPHM SCHPHL Reserved GPPCTL GPPRD GPPWR Reserved Not used CCREG1 CCREG2 CCREG3 CCREG4 CC_CTL Reserved HSOFFL HSOFFM Reserved SLAVE1 SLAVE2 TEST1 TEST2 GPSCTL CTL7 RD7 WR7 CTL6 RD6 WR6 CTL5 RD5 WR5 CTL4 RD4 WR4 CTL3 RD3 WR3 CTL2 RD2 WR2 CTL1 RD1 WR1 CTL0 RD0 WR0 W R W FF 00 7 RA7 ID17 ID0F ID07 REV7 LBW1 AN7 SC7 FR17 FR0F FR07 SCH7 6 RA6 ID16 ID0E ID06 REV6 5 RA5 ID15 ID0D ID05 REV5 4 RA4 ID14 ID0C ID04 REV4 3 RA3 ID13 ID0B ID03 REV3 SLH&V BURDIS DF0 AN3 SC3 FR13 FR0B FR03 SCH3 2 RA2 ID12 ID0A ID02 REV2 CVBSCLP LUMDIS Reserved AN2 SC2 FR12 FR0A FR02 SCH2 1 RA1 ID11 ID09 ID01 REV1 VFS1 CHRDIS Reserved AN1 SC1 FR11 FR09 FR01 SCH1 0 RA0 ID10 ID08 ID00 REV0 VFS0 PEDEN ACTREN PARITY SC0 FR10 FR08 FR00 SCH8 SCH0 R/W W R R R R R/W R/W * R/W R/W R/W R/W R/W R/W R/W 13 66 58 06 00 00 00 00 9C 87 C1 F1 00 00 DEFAULT hex YCDELAY RAMPEN CLAMPDIS CHRBW SYNCDIS DF1 DF2 LBW0 AN5 AN4 AN6 SC5 SC4 SC6 FR15 FR14 FR16 FR0D FR0C FR0E FR05 FR04 FR06 SCH5 SCH4 SCH6 HSOFF7 NCORSTD HCNT7 F1W1D6 F1W2D6 F2W1D6 F2W2D6 HSOFF6 VBITDIS HCNT6 F1W1D5 F1W2D5 F2W1D5 F2W2D5 HSOFF5 - F1W1D4 F1W2D4 F2W1D4 F2W2D4 HSOFF4 - F1W1D3 F1W2D3 F2W1D3 F2W2D3 F2ST HSOFF3 - F1W1D2 F1W2D2 F2W1D2 F2W2D2 F1ST HSOFF2 SL_HS0 HCNT2 TEST TEST TSURST F1W1D1 F1W2D1 F2W1D1 F2W2D1 F2EN HSOFF1 HSOFF9 HCNT9 HCNT1 F1W1D0 F1W2D0 F2W1D0 F2W2D0 F1EN HS0FF0 HSOFF8 HCNT8 HCNT0 R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W ----0C 7E 00 00 00 VSMODE HCNT5 REGISTER REGISTER FSC4SEL GENDITH GENLKEN SL_HS1 F_SWAP HCNT3 HCNT4 RESERVED FOR RESERVED FOR NOLOCK PALIDEN CHRMCLIP TRSEL 00 Table.1 Register map NOTE * For register HANC, bits 3, 4 and 5 are read only. Bits 1 and 2 are reserved. N/A = not applicable. For register PART ID0 the VP5511C value is AB Standard NTSC (default) PAL-B, G, H, I PAL-M PAL-N (Argentina) xx = don’t care. Lines/ Field field freq. Hz 59.94 525 625 525 625 50 59.94 50 SC_ADJ Number of Horizontal Subcarrier fSC/fH register pixels/line freq. kHz. freq. kHz. hex at 27MHz fH fSC 15.734266 3.57954545 1716 xx (455/2) 15.625000 4.43361875 (1135/4+1/625) 1728 9C 15.734266 3.57561189 1716 xx (909/4) 15.625000 3.58205625 (917/4+1/625) 1728 57 FREQ2-0 registers hex 87 C1 F1 A8 26 2B 87 9B C0 87 DA 51 Table.2 Line, field and subcarrier standards and register settings The calculation of the FREQ register value is according to the following formula:FREQ = 226 x fSC/PXCK hex, where PXCK = 27.00MHz Both NTSC and PAL-M values are rounded UP from the decimal number. PAL-B, D, G, H, I and N (Argentina) are rounded DOWN. The SC_ADJ value is derived from the adjustment needed to be added after 8 fields to ensure accuracy of the Subcarrier frequency. Note the SC_ADJ value of 9C required for PAL-B, D, G, H, I, is different to the default state of the register. In NTSC the NCO is reset at the end of every line, this can be disabled by setting the NCORSTD bit in SLAVE1, this allows the VP5311C to cope with line lengths that are not exactly as specified in REC656. 6 VP5311C/VP5511C REGISTER DETAILS BAR RA7-0 PART ID 2-0 ID17-00 REV ID REV7-0 GCR YCDELAY Base register Register address. Part number Chip part identification (ID) number. Revision number Chip revision ID number. Global Control Luma to Chroma delay. High = 37ns luma delay, this may be used to compensate for group delay in external filters. Low = normal operation (default). Modulated ramp enable. High = ramp output for differential phase and gain measurements. A 27MHz clock must be applied to PXCK pin. Low = normal operation (default). 1 = Slave to HS and VS inputs 1 = Enables clamp on composite output, to prevent flatenning of chroma peaks and troughs. Video format select VFS1 VFS0 0 0 NTSC (default) PAL-B,D,G,H,I,N(Argentina) 0 1 1 0 PAL-M 1 1 Reserved VOCR CLAMPDIS Video Output Control High = Clamp signal disable Low = normal operation with clamp signal enabled (default). Chroma bandwidth select. High = ±1·3MHz. Low = ±650kHz (default) High = Sync disable (in composite video signal). COMPSYNC is not affected. Low = normal operation with sync enabled (default). High = Chroma burst disable. Low = normal operation, with burst enabled (default). High = Luma input disable - force black level with synchronisation pulses maintained. Low = normal operation, with Luma input enabled (default). High = Chroma input disable - force monochrome. Low = normal operation, with Chroma input enabled (default). GPPCTL CTL7-0 FREQ2-0 FR17-00 Sub carrier frequency 24 bit Sub carrier frequency programmed via I2C bus, see table 2. FREQ2 is the most significant byte (MSB). Sub carrier phase offset 9 bit Sub carrier phase relative to the 50% point of the leading edge of the horizontal part of composite sync. SCHPHM bit 0 is the MSB. The nominal value is zero. This register is used to compensate for delays external to the VP5311C/VP5511C. General purpose port control Each bit controls port direction Low = output High = input General purpose port read data I2C bus read from general purpose port (only INPUTS defined in GPPCTL) General purpose port write data I2C bus write to general purpose port (only OUTPUTS defined in GPPCTL) Closed Caption register 1 Field one (line 21), first data byte Closed Caption register 2 Field one (line 21), second data byte Closed Caption register 3 Field two (line 284), first data byte HANC LBW1-0 PEDEN High = Pedestal (set-up) enable a 7·5 IRE pedestal on lines 23-262 and 286-525. Valid for NTSC/PAL-M only Horizontal Ancillary Data Control Luma filter control LBW1 LBW0 0 0 0 1 1 X -3dB Bandwidth 6.16MHz 4.34MHz 2.79MHz DF2-0(read only) Digital Field Identification, 000=Field1 ANCTREN Ancillary timing reference enable. When High use FIELD COUNT from ancillary data stream. When low, data is ignored. ANCID AN7-1 Parity Ancillary data ID Ancillary data ID Parity bit (odd) Only ancillary data in REC 656 data stream with the same ID as this byte will be decoded by the VP5311C/VP5511C to produce H and V synchronisation and FIELD COUNT. Sub Carrier Adjust Sub carrier frequency seed value, see table 2. RAMPEN SLH&V CVBSCLMP SC_ADJ SC7-0 VFS1-0 SCHPHM-L SCH8-0 CHRBW SYNCDIS GPPRD RD7-0 BURDIS GPPWR WR7-0 LUMDIS CCREG1 F1W1D6-0 CCREG2 F1W2D6-0 CCREG3 F2W1D6-0 CHRDIS 7 VP5311C/VP5511C CCREG4 F2W2D6-0 CC_CTL F1ST Closed Caption register 4 Field two (line 284), second data byte Closed Caption control register Field one (line 21) status High = data has been encoded Low = new data has been loaded to CCREG1-2 Field two (line 284) status High = data has been encoded Low = new data has been loaded to CCREG3-4 Closed Caption field one (line 21) High = enable Low = disable (default) Closed Caption field two (line 284) High = enable Low = disable (default) HS offset This is a 10 bit number which allows the user to offset the start of digital data input with reference to the pulse HS. H &V Slave mode control register 1 = NCO Line Reset Disable (NTSC only) 0 = Video blanked when Rec656 V bit set 1 = V bit is ignored 0 = Standard Vsync I/P 1 = Even/Odd Field I/P The odd and even fields are swapped Selects pixel sample (0 to 3) As HCNT7-0 but MSBs H &V Slave position register Adjusts for delay at which pixel data occurs relative to HS GPS Control When high, REFSQ = 4xFSC and GPP bit D6 is forced to become an input for a SCSYNC signal (high = reset), which provides a synchronous phase reset for FSC divider. Low = normal operation with REFSQ = 1xFSC. (default). 1 = Gen lock dither added. High = enable Genlock to REFSQ signal input. Low = internal subcarrier generation (default). Genlock status bit (read only) Low = Genlocked. High = cannot lock to REFSQ. This bit is cleared by reading and set again if lock cannot be attained. High = enable external PAL ID phase control and GPP bit D7 is forced to become an input for PAL ID switch signal, (GPP bit D7 - Low = +135°,High = -135°). TSURST Low = normal operation, internal PAL ID phase switch is used (default). High = chip soft reset. Registers are NOT reset to default values. Low = normal operation (default). High = enable clipping of chroma data when luma goes below black level and is clipped. Low = no chroma clipping (default). High = master mode, GPP bits D0 - 4 are forced to become a video timing port with VS, HS and FIELD outputs. Low = slave mode, timing from REC656. or H & V slave if SLH&V bit set CHRMCLIP F2ST TRSEL F1EN F2EN I2C BUS CONTROL INTERFACE I2C bus address A6 0 A5 0 A4 0 A3 1 A2 1 A1 SA2 A0 SA1 R/ W X HSOFFM-L HSOFF9-0 SLAVE1 NCORSTD VBITDIS VSMODE F_SWAP SL_HS1-0 HCNT9-8 SLAVE2 HCNT7-0 GPSCTL FSC4SEL GENDITH GENLKEN The serial microprocessor interface is via the bidirectional port consisting of a data (SDA) and a clock (SCL) line. It is compatible to the Philips I2C bus standard (Jan. 1992 publication number 9398 393 40011). The interface is a slave transmitter - receiver with a sub-address capability. All communication is controlled by the microprocessor. The SCL line is input only. The most significant bit (MSB) is sent first. Data must be stable during SCL high periods. A bus free state is indicated by both SDA and SCL lines being high. START of transmission is indicated by SDA being pulled low while SCL is high. The end of transmission, referred to as a STOP, is indicated by SDA going from low to high while SCL is high. The STOP state can be omitted if a repeated START is sent after the acknowledge bit. The reading device acknowledges each byte by pulling the SDA line low on the ninth clock pulse, after which the SDA line is released to allow the transmitting device access to the bus. The device address can be partially programmed by the setting of the pins SA1 and SA2. This allows the device to respond to one of four addresses, providing for system flexibility. The I2C bus address is seven bits long with the last bit indicating read / write for subsequent bytes. The first data byte sent after the device address, is the sub-address - BAR (base address register). The next byte will be written to the register addressed by BAR and subsequent bytes to the succeeding registers. The BAR maintains its data after a STOP signal. NTSC/PAL Video Standards Both NTSC (4-field, 525 lines) and PAL (8-field, 625 lines) video standards are supported by the VP5311C/VP5511C. All raster synchronisation, colour sub-carrier and burst characteristics are adapted to the standard selected. The VP5311C/VP5511C generates outputs which follow the requirements of SMPTE 170M and CCIR 624 for PAL signals. The device supports the following: NTSC, PAL B, D, G, H, I, N (Argentina) and M. NOLOCK PALIDEN 8 VP5311C/VP5511C Video Blanking The VP5311C/VP5511C automatically performs standard composite video blanking. Lines 1-9, 264-272 inclusive, as well as the last half of line 263 are blanked in NTSC mode. In PAL mode, lines 1-5, 311-318, 624-625 inclusive, as well as the last half of line 623 are blanked. The V bit within REC656 defines the video blanking when TRSEL (bit 0 of GPSCTL register) is set low. When in MASTER mode with TRSEL set high the video encoder is still enabled. Therefore if these lines are required to be blank they must have no video signal input. Interpolator The luminance and chrominance data are separately passed through interpolating filters to produce output sampling rates double that of the incoming pixel rate. This reduces the sinx/x distortion that is inherent in the digital to analog converters and also simplifies the analog reconstruction filter requirements. Digital to Analog Converters The VP5311C/VP5511C contains three 9 bit digital to analog converters which produce the analog video signals. The DACs use a current steering architecture in which bit currents are routed to one of two outputs; thus the DAC has true and complementary outputs. The complementary output is connected to GND internally. The use of identical current sources and current steering their outputs means that monotonicity is guaranteed. An on-chip voltage reference of 1.050V provides the necessary biasing. However, the VP5311C/VP5511C may be used in applications where an external 1V reference is provided on the VREF pin, to adjust the video levels. In this case, the external reference should be temperature compensated and provide a low impedance output. The full-scale output currents of the DACs is set by an external 769Ω resistor between the DACGAIN and a GND pins. An on-chip loop amplifier stabilises the full-scale output current against temperature and power supply variations. The analog outputs of the VP5311C/VP5511C are capable of directly driving singly terminated 75Ω loads. For this application the DACGAIN resistor is simply doubled. Luminance, Chrominance and Composite Video Outputs The Luminance video output (LUMAOUT pin 45) drives a 37.5Ω load at 1.0V, sync tip to peak white. It contains only the luminance content of the image plus the composite sync pulses. In the NTSC mode, a set-up level offset can be added during the active video portion of the raster. The Chrominance video output (CHROMAOUT pin 49) drives a 37.5Ω load at levels proportional in amplitude to the luma output (40 IRE pk-pk burst). This output has a fixed offset current which will produce approximately a 0.5V DC bias across the 37.5Ω load. Burst is injected with the appropriate timing relative to the luma signal. The composite video output (COMPOUT pin 47) will also drive a 37.5Ω load at 1.0V, sync tip to peak white. It contains both the luminance and chrominance content of the signal plus the composite sync pulses. The CVBS DAC output clipping feature limits the digital data going into the DAC so that if it goes outside the range it is limited to the maximum or minimum (511 or 000). This feature is permanently enabled. When CVBSCLP in register GCR is set to a '1' an envelope prediction circuit is enabled that establishes if the chroma and luma added together is likely to go outside the CVBS DAC limits. If it is, then a smooth rounding of the chroma peaks is made to stop this happening. This prevents any high frequency components being produced as with the default clipping function which will produce flat peaks. In practice there will be some loss of saturation in the colour. Output sinx/x compensation filters are required on all video output, as shown in the typical application diagram, see figs. 8 & 9. Video Timing - Slave sync mode The VP5311C/VP5511C has an internal timing generator which produces video timing signals appropriate to the mode of operation. In the default (following reset) slave mode, all timing signals are derived from the input clock, PXCK, which must be derived from a crystal controlled oscillator. Input pixel data is latched on the rising edge of the PXCK clock. The video timing generator produces the internal blanking and burst gate pulses, together with the composite sync output signal, using timing data (TRS codes) from the Ancillary data in the REC656 input signal. H & V Slave Mode HCNT To ensure that the incoming data is sampled correctly a 10 bit binary number (HCNT) has to be programmed into the SLAVE1 and 2 registers. This will allow the device's internal horizontal counter to align with the video data, each bit represents one 13.5MHz cycle. To calculate this use the formula below: NTSC/PALM HCNT = SN + 119 (SN = 0 - 738) HCNT = SN - 739 (SN = 739 - 857) PAL HCNT = SN + 127 (SN = 0 - 736) HCNT = SN - 737 (SN = 737 - 863) where SN is Rec. 656/601 sample number on which the negative edge of HSYNC occurs. SL_HS A further adjustment is also required to ensure that the falling edge of HSYNC occurs on a Y sample that precedes a Cr sample. The bits SL_HS1-0 introduce a delay of 0-3 27MHz samples in the CbYCrY sequence, failure to set this correctly will mean corruption of the colour or colour being interpreted as luma. F_SWAP If the field synchronisation is wrong it can be swapped by setting this bit. V_SYNC When set to a '1' this bit allows an odd/even square wave to provide the field synchronisation. Example NTSC HSYNC occurs on Rec656 sample 721 (end of active video), then; HCNT = 721 + 119 = 839 = 348 Hex SL_HS = 10 (for correct sample) 9 VP5311C/VP5511C To set slave H & V the SLH&V bit should be set to '1' (reg 04). Video Timing - Master sync mode When TRSEL (bit 0 of GPSCTL register) is set high, the VP5311C/5511C operates in a MASTER sync mode, all REC656 timing reference codes are ignored and GPP bits D0 - 4 become a video timing port with VS, HS and FIELD outputs. The PXCK signal is, however, still used to generate all internal clocks. When TRSEL is set high, the direction setting of bits 4 - 0 of the GPPCTL register is ignored. VS is the start of the field sync datum in the middle of the equalisation pulses. HS is the line sync which is used by the preceding MPEG2 decoder to define when to output digital video data to the VP5311C/5511C. HS offset The position of the falling edge of HS relative to the first data Cb0, can be programmed in HSOFFM-L registers, see figure 4, this is called the pipeline delay and may need adjusting for a particular application. This is done by programming a 10 bit number called HSOFF into the HSOFFM and HSOFFL registers, HSOFFM being the most significant two bits and HSOFFL the least significant eight bits. A default value of 07EH is held in the registers. The value to program into HSOFF can be looked up in tables 3 &4: where NCK = number of 13.5MHz clock cycles between the falling edge of HS and Cb0 (first data I/P on PD7-0) see fig. 4. NCK 0 to 120 121 to 183 184 to 857 HSOFF 126 to 6 863 to 801 800 to 127 Comment HS normal (64 cks) HS pulse shortened* HS normal (64 cks) high (in GPSCTL register), a 4 x sub carrier frequency signal may be input to REFSQ. In this case, the Genlock circuit can be reset to the required phase of REFSQ, by supplying a pulse to SCSYNC (pin 7). The frequency of SCSYNC can be at sub carrier frequency, but once per line, or once per field could be adequate, depending on the application. When GENLKEN is set high, the direction setting of bit 6 in the GPPCTL register is igonred. PALID Input When in Genlock mode with GENLKEN set high (in GPSCTL register), the VP5311/5511C requires a PAL phase identification signal, to define the correct phase on every line. This is supplied to PALID input (pin 8), High = -135° and low = +135°. The signal is asynchronous and should be changed before the sub carrier burst signal. PALID input is enabled by setting PALIDEN high (in GPSCTL register). When GENLKEN is high, the direction setting of bit 7 of the GPPCTL register is ignored Master Reset The VP5311C/VP5511C must be initialised with the RESET pin 27. This is an asynchronous active low signal and must be active for a minimum of 200ns in order for the VP5311C/VP5511C to be reset. The device resets to line 254 in NTSC and line 301 in PAL and start of horizontal sync (i.e. line blanking active). There is no on-chip power on reset circuitry. Line 21 coding Two bytes of data are coded on the line 21 of each field, see figure 7. In the NTSC Closed Caption service, the default state is to code on line 21 of field one only. An additional service can also be provided using line 21 (284) of the second field. The data is coded as NRZ with odd parity, after a clock run-in and framing code. The clock run-in frequency = 0.5034965MHz which is related to the nominal line period, D = H / 32. D = 63.55555556 / 32µs Two data bytes per field are loaded via I2C bus registers CCREG1-4. Each field can be independently enabled by programming the enable bits in the control register (CC_CTL). The data is cleared to zero in the Closed Caption shift registers after it has been encoded by the VP5311C/ VP5511C. Two status bits are provided (in CC_CTL), which are cleared when data is written to the registers and set high when the data has been encoded on the Luma signal. The data is cleared to zero in the Closed Caption shift registers after it has been encoded by the VP5311C/VP5511C. The next data bytes must be written to the registers when the status bit goes high, otherwise the Closed Caption data output will contain Null characters. Null characters are invisible to a Closed Caption reciever. The MSB (bit 7) is the parity bit and is automatically added by the encoder. Table.3 for NTSC and PAL-M NCK 0 to 131 132 to 194 195 to 863 HSOFF 137 to 6 869 to 807 806 to 138 Comment HS normal (64 cks) HS pulse shortened* HS normal (64 cks) Table.4 for PAL-B, D, G, H, I, N Decreasing HSOFF advances the HS pulse (numbers are in decimal). *HS pulse shortened means that the width of the pulse will be less than the normal 64 13.5MHz clock cycles. The interruption in the sequence of values is because the HS signal is jumping across a line boundary to the previous line as the offset is increased. The register default value is 7EH and this sets Nck to 0, ie. the HS negative edge and Cb0 are coincident in NTSC mode. Genlock using REFSQ input The VP5311C/5511C can be Genlocked to another video source by setting GENLKEN high (in GPSCTL register) and feeding a phase coherent sub carrier frequency signal into REFSQ. Under normal circumstances, REFSQ will be the same frequency as the sub carrier. But by setting FSC4SEL 10 VP5311C/VP5511C PXCK Input (27MHz) HS Nck=1 Nck=0 Cb0 Y0 Cr0 Y1 t SU; PD t HD; PD Cb1 Y2 Cr1 Y3 Pixel Data Input (PD[7,0]) Fig.4 REC 656 interface with HS output timing 2:1 mux REFSQ 0 Divide by 4 Synchronous Counter RESET 1 fSC Input to Genlocking Block Q SC_SYNC REFSQ FSC4_SEL (register bit) t PWH; SC_SYNC tSU; SC_SYNC SC_SYNC t HD; SC_SYNC Q Fig.5 REFSQ and SC_SYNC input timing 11 VP5311C/VP5511C Pixel Data Input (PD[7,0]) Sample Number 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 Y719 $FF $00 $00 $XY ANCILLARY DATA... EAV SEQUENCE t PWL; PXCK PXCK Input (27MHz) t PWH; PXCK t SU; PD t HD; PD t DUR; PALID t SU; PALID PALID Stable Input (PALID) t HD; PALID Fig.6 PALID input timing TIMING INFORMATION Parameters Master clock frequency (PXCK input) PXCX pulse width, HIGH PXCX pulse width, LOW PXCX rise time PXCX fall time PD7-0 set up time PD7-0 hold time SCSYNC set up time SCSYNC hold time PALID set up time PALID hold time PALID duration Output delay PXCK to COMPSYNC PXCK to CLAMP Note: Timing reference points are at the 50% level. Digital C LOAD