Philips TDA9160A-N3 Datasheet

DATA SH EET
Preliminary specification File under Integrated Circuits, IC02
December 1991
INTEGRATED CIRCUITS
TDA9160
PAL/NTSC/SECAM decoder/sync processor
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Philips Semiconductors Preliminary specification
PAL/NTSC/SECAM decoder/sync processor TDA9160
FEATURES
Multistandard PAL, NTSC and SECAM
I2C-bus controlled
I2C-bus addresses can be selected
by hardware
Alignment free
Few external components
Designed for use with baseband
delay lines
Integrated video filters
Horizontal and vertical drive output
East-West correction drive output
Two CVBS inputs
S-VHS input
Vertical divider system
HA synchronization pulse
Two level sandcastle pulse
GENERAL DESCRIPTION
The TDA9160 is an I2C-bus controlled, alignment-free PAL/NTSC/SECAM decoder/processor. The device contains horizontal and vertical drive outputs and an east-west correction drive circuit. The TDA9160 has been designed for use with baseband chrominance delay lines and DC-coupled vertical and east-west output circuits. The device has three inputs, two for CVBS and one for S-VHS. The main signal is available at the luminance and colour difference outputs and, also, at the TXT output (unprocessed). The signal at the PIP output can be selected independently from the main signal. The circuit provides a drive pulse for the horizontal output stage, a differential sawtooth current for the vertical output stage and an east-west
drive current for the EW output stage. These signals can be used to provide geometry correction of the picture. A two level sandcastle pulse and an H
A
pulse are made available for synchronization purposes .The I2C-bus address of the TDA9160 can be programmed by hardware.
Fig.1 Block diagram.
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Philips Semiconductors Preliminary specification
PAL/NTSC/SECAM decoder/sync processor TDA9160
QUICK REFERENCE DATA
ORDERING INFORMATION
Note
1. SOT232-1; 1996 December 2.
SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT
V
CC
positive supply voltage 7.2 8.0 8.8 V
I
CC
supply current 50 mA
V
24,26(p-p)
CVBS input voltage (peak-to-peak value) 1.0 V
V
23(p-p)
S-VHS luminance input voltage (peak-to-peak value) 1.0 V
V
22(p-p)
S-VHS chrominance burst input voltage (peak-to-peak value)
0.3 V
V
1(p-p)
luminance output voltage (peak-to-peak value) 0.45 V
V
25(p-p)
teletext output voltage (peak-to-peak value) 1.0 V
V
2(p-p)
chrominance output voltage (R-Y) (peak-to-peak value) PAL/NTSC 525 mV
V
2(p-p)
chrominance output voltage (R-Y) (peak-to-peak value) SECAM 1.05 V
V
3(p-p)
chrominance output voltage (B-Y) (peak-to-peak value) PAL/NTSC 665 mV
V
3(p-p)
chrominance output voltage (B-Y) (peak-to-peak value) SECAM 1.33 V
V
10
HA output voltage 5.0 V
I
15,16(p-p)
vertical drive output current (peak-to-peak value) 1 mA
I
18
horizontal drive output current −−10 mA
I
17
EW drive output current −−0.9 mA
V
6
sandcastle clamping voltage level 4.5 V
V
6
sandcastle blanking voltage level 2.5 V
EXTENDED TYPE
NUMBER
PACKAGE
PINS PIN POSITION MATERIAL CODE
TDA9160 32 SDIL plastic SOT232
(1)
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Philips Semiconductors Preliminary specification
PAL/NTSC/SECAM decoder/sync processor TDA9160
Fig.2 Pin configuration.
PINNING
SYMBOL PIN DESCRIPTION
Y 1 luminance output
(R-Y) 2 chrominance output
(B-Y) 3 chrominance output
SCL 4 serial clock input SDA 5 serial data input/output SC 6 sandcastle output V
CC
7 positive supply input DEC 8 positive supply decoupling DGND 9 digital ground H
A
10 horizontal acquisition
synchronization pulse
V
saw
11 vertical sawtooth
I
ref
12 input current reference AGND1 13 analog ground EHT/PROT 14 EHT tracking and over-voltage
protection
VOUT
A
15 vertical drive output A VOUT
B
16 vertical drive output B EWOUT 17 east-west drive output HOUT 18 horizontal drive output HFB 19 horizontal flyback input PIP 20 picture-in-picture output HPLL 21 horizontal PLL filter SVHSC 22 S-VHS chrominance input SVHSY 23 S-VHS luminance input CVBS2 24 CVBS2 input TXT 25 teletext output CVBS1 26 CVBS1 input AGND2 27 analog ground FILT
ref
28 filter reference decoupling PLL 29 colour PLL filter XTAL 30 reference crystal input XTAL2 31 second crystal input SEC
ref
32 SECAM reference decoupling
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Philips Semiconductors Preliminary specification
PAL/NTSC/SECAM decoder/sync processor TDA9160
FUNCTIONAL DESCRIPTION
The TDA9160 is an I2C-bus controlled, alignment free PAL/NTSC/SECAM colour decoder/sync processor/deflection controller which has been designed for use with baseband chrominance delay lines. In the standard operating mode the I2C-bus address is 8A . If the TXT output is connected to the positive rail the address will change to 8E
The standards which the TDA9160 can decode are dependent on the choice of external crystals. If a
4.4 MHz and a 3.6 MHz crystal are used then SECAM, PAL 4.4/3.6 and NTSC 4.4/3.6 can be decoded. If two
3.6 MHz crystals are used then only PAL 3.6 and NTSC 3.6 can be decoded. Which 3.6 MHz standards can be decoded is dependent on the exact frequencies of the crystal. In an application where not all standards are required only one crystal is sufficient (in this instance the crystal must be connected to the reference crystal input (pin 30)). If a 4.4 MHz crystal is used it must always be connected to pin 30. Both crystals are used to provide a reference for the filters and the horizontal PLL, however, only the reference crystal is used to provide a reference for the SECAM demodulator. To enable the calibrating circuits to be adjusted exactly two bits from the I2C-bus address are used to indicate which crystals are connected to the IC.
The standard identification circuit is a digital circuit without external components; the search loop is illustrated in Fig.3.
The decoder (via the I2C-bus) can be forced to decode either SECAM or PAL/NTSC (but not PAL or NTSC). Crystal selection can also be forced. Information, concerning which
standard and which crystal have been selected and whether the colour killer is ON or OFF is provided by the read out. Using the forced-mode does not affect the search loop, it does, however, prevent the decoder from reaching or staying in an unwanted state. The identification circuit skips impossible standards (e.g. SECAM when no 4.4 MHz crystal is fitted) and illegal standards (e.g. forced mode). To reduce the risk of wrong identification PAL has priority over SECAM (only line identification is used for SECAM).
The TDA9160 has two CVBS inputs and one S-VHS input which can be selected via the I
2
C-bus. The input selector can also be switched to enable CVBS2 to be processed, providing that there is no S-VHS signal present at the input. If the input selector is set to CVBS2 it will switch to S-VHS if an S-VHS sync pulse is detected at the luminance input. The S-VHS detector output can be read via the I2C-bus. If the voltage at either the S-VHS luminance or the chrominance input (pins 22 and 23) exceeds +5.5 V the IC will revert to test mode.
The TDA9160 also provides outputs for picture-in-picture and teletext (PIP pin 20 and TXT pin 25). The decoder input signal can be switched directly to the TXT output. The PIP output signal can be selected independently from the TXT output. If S-VHS is selected at the TXT output only the luminance signal will be present; if S-VHS is selected at the PIP output then the luminance and chrominance signals will be added.
All filters, including the luminance delay line, are an integral part of the IC. The filters are gyrator-capacitor type filters. The resonant frequency of the filters is controlled by a circuit that uses the active crystal to tune the
SECAM Cloche filter during the vertical flyback time. The remaining filters and the delay line are matched to this filter. The filters can be switched to either 4.43 MHz,
4.28 MHz or 3.58 MHz irrespective of the frequency of the active crystal. The switching is controlled by the identification circuit.
The S-VHS luminance signal does not pass through the notch filter to preserve bandwidth. The luminance delay line delivers the Y signal to the output 40 ns after the (R-Y) and
(B-Y) signals. This compensates for the delay of the external chrominance delay lines.
The PAL/NTSC demodulator employs an oscillator that can operate with either crystal (3.6 or 4.4 MHz). If the I2C-bus indicates that only one crystal is connected it will always connect to the crystal at the reference input (pin 30).
The Hue signal, which is adjustable via the I2C-bus, is gated during the burst for NTSC signals.
The SECAM demodulator is an auto-calibrating PLL demodulator which has two references. The reference crystal, to force the PLL to the desired free-running frequency and the bandgap reference, to obtain the correct absolute value of the output signal. The VCO of the PLL is calibrated during each vertical flyback period, when the reference crystal is active. When the second crystal is active the VCO is not calibrated. During this time the frequency of the VCO is kept constant by applying a constant voltage to its control input. If the reference crystal is not 4.4 MHz the decoder will not produce the correct SECAM signals.
The main part of the sync circuit is a 432 × fH (6.75 MHz) oscillator the frequency of which is divided by 432
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Philips Semiconductors Preliminary specification
PAL/NTSC/SECAM decoder/sync processor TDA9160
to lock the phase 1 loop to the incoming signal. The time constant of the loop can be forced by the I2C-bus (fast or slow). If required the IC can select the time constant, depending on the noise content of the input signal and whether the loop is phase locked or not (medium or slow). The free-running frequency of the oscillator is determined by a digital control circuit that is locked to the active crystal.
When a power-on-reset pulse is detected the frequency of the oscillator is switched to a frequency greater than 6.75 MHz to protect the horizontal output transistor. The oscillator frequency is reset to
6.75 MHz when the crystal indication bits have been loaded into the IC. To ensure that this procedure does not fail it is absolutely necessary to send subaddress 00 before subaddress
01. Subaddress 00 contains the crystal indication bits, when subaddress 01 is received the line oscillator calibration will be initiated. The calibration is terminated when the oscillator frequency reaches
6.75 MHz. The oscillator is again calibrated when an out-of-lock condition with the input signal is realised by the coincidence detector. Again the calibration will be terminated when the oscillator frequency reaches 6.75 MHz. The phase 1 loop can be opened using the I2C-bus. This is to facilitate On Screen Display (OSD) information. If there is no input signal or a very noisy input signal the phase 1 loop can be opened to provide a stable line frequency and thus a stable picture.
The sync part provides an HA pulse that is coupled to the processed CVBS signal.
The horizontal drive signal can be switched off via the I2C-bus (standby mode). The horizontal drive is also switched off when the over-voltage
protection circuit trips or when a POR is detected. Should either of these two conditions occur the IC will return to the normal operating mode when the appropriate command is received via the I2C-bus. The duty cycle of the horizontal drive signal is increased from 2%, at start-up, to a constant value of 55% in approximately 300 lines. The two-level sandcastle pulse provides a combined horizontal and vertical blanking signal and a clamping pulse coupled to the display section of the TV.
The vertical sawtooth generator drives the geometry processing circuits which provide control for the horizontal shift, EW width, EW parabola/width ratio, EW corner/parabola ratio, trapezium correction, vertical slope, vertical shift, vertical amplitude and the S-correction. All of these control functions can be set via the I2C-bus. The geometry processor has a differential current output for the vertical drive signal and a single-ended output for the EW drive. Both the vertical drive and the EW drive outputs can be modulated for EHT compensation. The EHT compensation pin (pin 14) can also be used for over-voltage protection. De-interlace of the vertical output can be set via the I2C-bus.
The vertical divider system has a fully integrated vertical sync separator. The divider can accommodate both 50 and 60 Hz systems; it can either locate the field frequency automatically or it can be forced to the desired system via the I2C-bus. A block diagram of the vertical divider system is illustrated in Fig.4. The divider system operates at 432 times the horizontal line frequency. The line counter receives enable pulses at twice the line frequency, thereby counting two lines per pulse. A state diagram of the controller is illustrated in Fig.5. Because it is
symmetrical only the right hand part will be described.
Depending on the previously found field frequency, the controller will be in one of the 'count' states. When the line counter has counted 488 pulses (i.e. 244 lines of the video input signal) the controller will move to the next state depending on the output of the norm counter. This can be either NORM, NEAR-NORM or NO-NORM depending on the position of the vertical sync pulse in the previous fields. When the counter is in the NORM state it generates the vertical sync pulse (VSP) automatically and then, when the line counter is at LC = 626, moves to the WAIT state. In this condition it waits for the next pulse of the double line frequency signal and then moves to the COUNT state of the current field frequency. When the controller returns to the COUNT state the line counter will be reset half a line after the start of the vertical sync pulse of the video input signal. When the controller is in the NEAR-NORM state it will move to the COUNT state if it detects the vertical sync pulse within the NEAR-NORM window (i.e. 622 < LC < 628). If no vertical sync pulse is detected, the controller will move back to the COUNT state when the line counter reaches LC = 628. The line counter will then be reset. When the controller is in the NO-NORM state it will move to the COUNT state when it detects a vertical sync pulse and reset the line counter. If a sync pulse is not detected before LC = 722 (if the phase loop is locked in forced mode) it will move to the COUNT state and reset the line counter. If the phase loop is not locked the controller will move back to the COUNT state when LC = 628. The forced mode option keeps the controller in either the left-hand side (60 Hz) or the
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Philips Semiconductors Preliminary specification
PAL/NTSC/SECAM decoder/sync processor
TDA9160
right-hand side (50 Hz) of the state diagram.
Figure 6 illustrates the state diagram of the 'norm' counter which is an up/down counter that counts up if it finds a vertical sync pulse within the selected window. In the NEAR-NORM and NORM states the first correct vertical sync pulse after one or more incorrect vertical sync pulses is processed as an incorrect pulse. This procedure prevents the
system from staying in the NEAR-NORM or NORM state if the vertical sync pulse is correct in the first field and incorrect in the second field. If no vertical sync pulse is found in the selected window this will always result in a down pulse for the 'norm' counter.
Figure 7 illustrates the timing of the display sandcastle (DSC) and the reset pulse of the vertical sawtooth with respect to the input signal
I
2
C-bus protocol
If the TXT output is connected to the positive supply the address will change from 8A to 8E.
Valid subaddresses = 00 to 0F Auto-increment mode available for subaddresses.
Subaddress 00 must always be sent before subaddress 01 in order to protect the horizontal output transistor.
Table 1 Slave address (8A)
Table 2 Inputs
Table 3 Outputs
A6 A5 A4 A3 A2 A1 A0 R/
W
10001X1X
SUBADDRESS MSB LSB
00 INA INB INC IND FOA FOB XA XB 01 FORF FORS DL STB POC FM SAF FRQF 02 −−HU5 HU4 HU3 HU2 HU1 HU0 03 −−HS5 HS4 HS3 HS2 HS1 HS0 04 −−EW5 EW4 EW3 EW2 EW1 EW0 05 −−PW5 PW4 PW3 PW2 PW1 PW0 06 −−CP5 CP4 CP3 CP2 CP1 CP0 07 −−TC5 TC4 TC3 TC2 TC1 TC0 08 −−VS5 CS4 VS3 VS2 VS1 VS0 09 −−VA5VA4VA3VA2VA1VA0 0A −−SC5 SC4 SC3 SC2 SC1 SC0 0B SBL VSH5 VSH4 VSH3 VSH2 VSH1 VSH0
ADDRESS POR FSI STS SL PROT SAK SBK FRQ
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Philips Semiconductors Preliminary specification
PAL/NTSC/SECAM decoder/sync processor TDA9160
Fig.3 Search loop of the identification circuit.
Fig.4 Block diagram of the vertical divider system.
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Philips Semiconductors Preliminary specification
PAL/NTSC/SECAM decoder/sync processor TDA9160
Fig.5 State diagram of the vertical divider system.
Fig.6 State diagram of the ‘norm’ counter.
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