TI1 DS90UB926Q 5 - 85 mhz 24-bit color fpd-link iii deserializer with bidirectional control channel Datasheet

DS90UB926Q
5 - 85 MHz 24-bit Color FPD-Link III Deserializer with Bidirectional
Control Channel
General Description
Features
The DS90UB926Q deserializer, in conjunction with the
DS90UB925Q serializer, provides a complete digital interface
for concurrent transmission of high-speed video, audio, and
control data for automotive display and image sensing applications.
This chipset translates a parallel RGB Video Interface into a
single pair high-speed serialized interface. The serial bus
scheme, FPD-Link III, supports full duplex of high speed forward data transmission and low speed backchannel communication over a single differential link. Consolidation of video
data and control over a single differential pair reduces the interconnect size and weight, while also eliminating skew issues
and simplifying system design.
The DS90UB926Q deserializer recovers the RGB data, three
video control signals and four synchronized I2S audio signals.
It extracts the clock from a high speed serial stream. An output
LOCK pin provides the link status if the incoming data stream
is locked, without the use of a training sequence or special
SYNC patterns, as well as a reference clock.
The DS90UB926Q deserializer has a 31-bit parallel LVCMOS
output interface to accommodate the RGB, video control, and
audio data.
An adaptive equalizer optimizes the maximum cable reach.
EMI is minimized by output SSC generation (SSCG) and enhanced progressive turn-on (EPTO) features.
● Bidirectional control interface channel interface with I2C
compatible serial control bus
● Supports high definition (720p) digital video format
● RGB888 + VS, HS, DE and synchronized I2S audio
supported
● 5 to 85 MHz PCLK supported
● Single 3.3V Operation with 1.8V or 3.3V compatible
●
●
●
●
●
●
●
●
●
●
●
●
●
LVCMOS I/O interface
AC-coupled STP Interconnect up to 10 meters
Parallel LVCMOS video outputs
I2C compatible serial control bus for configuration
DC-balanced & scrambled Data w/ Embedded Clock
Adaptive cable equalization
Supports repeater application
@ SPEED Link BIST Mode and LOCK status pin
Image Enhancement (White Balance and Dithering) and
Internal pattern generation
EMI Minimization (SSCG and EPTO)
Low power modes minimize power dissipation
Automotive grade product: AEC-Q100 Grade 2 qualified
>8kV HBM and ISO 10605 ESD rating
Backward compatible to FPD-Link II
Applications
●
●
●
●
Automotive Display for Navigation
Rear Seat Entertainment Systems
Automotive Drive Assistance
Automotive Megapixel Camera Systems
TRI-STATE® is a registered trademark of National Semiconductor Corporation.
PRODUCTION DATA information is current as of
publication date. Products conform to specifications per
the terms of the Texas Instruments standard warranty.
Production processing does not necessarily include
testing of all parameters.
301434 SNLS422
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
Typical Displays Applications Diagram
30143427
Typical Display Applications Diagram
30143426
2
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
DS90UB926Q Pin Diagram
30143419
DS90UB926Q — Top View
Copyright © 1999-2012, Texas Instruments Incorporated
3
DS90UB926Q
Pin Descriptions
Pin Name
Pin #
I/O, Type
Description
LVCMOS Parallel Interface
ROUT[23:0] / 41, 40, 39, 37, O, LVCMOS
R[7:0], G
36, 35, 34, 33, w/ pull down
[7:0], B[7:0] 28, 27, 26, 25,
23, 22, 21, 20,
19, 18, 17, 14,
12, 11, 10, 9
Parallel Interface Data Output Pins.
Leave open if unused.
ROUT0 / R0 can optionally be used as GPIO0 and ROUT1 / R1 can optionally be used as
GPIO1.
ROUT8 / G0 can optionally be used as GPIO2 and ROUT9 / G1 can optionally be used as
GPIO3.
ROUT16 / B0 can optionally be used as GPO_REG4 and ROUT17/ B1 can optionally be
used as I2S_DB / GPO_REG5.
HS
8
O, LVCMOS Horizontal Sync Output Pin
w/ pull down Video control signal pulse width must be 3 PCLKs or longer to be transmitted when the
Control Signal Filter is enabled. There is no restriction on the minimum transition pulse
when the Control Signal Filter is disabled. The signal is limited to 2 transitions per 130
PCLKs.
See Table 9
VS
7
O, LVCMOS Vertical Sync Output Pin
w/ pull down Video control signal is limited to 1 transition per 130 PCLKs. Thus, the minimum pulse width
is 130 PCLKs.
DE
6
O, LVCMOS Data Enable Output Pin
w/ pull down Video control signal pulse width must be 3 PCLKs or longer to be transmitted when the
Control Signal Filter is enabled. There is no restriction on the minimum transition pulse
when the Control Signal Filter is disabled. The signal is limited to 2 transitions per 130
PCLKs.
See Table 9
PCLK
5
O, LVCMOS Pixel Clock Output Pin. Strobe edge set by RFB configuration register. SeeTable 9
w/ pull down
I2S_CLK,
I2S_WC,
I2S_DA
MCLK
1, 30, 45
60
O, LVCMOS Digital Audio Interface Data Output Pins
w/ pull down Leave open if unused
I2S_CLK can optionally be used as GPO_REG8, I2S_WC can optionally be used as
GPO_REG7, and I2S_DA can optionally be used as GPO_REG6.
O, LVCMOS I2S Master Clock Output. x1, x2, or x4 of I2S_CLK Frequency.
w/ pull down
Optional Parallel Interface
I2S_DB
18
O, LVCMOS
w/ pull down
Second Channel Digital Audio Interface Data Output pin at 18–bit color mode and set by
MODE_SEL or configuration register
Leave open if unused
I2S_B can optionally be used as BI or GPO_REG5.
GPIO[3:0]
27, 28, 40, 41 I/O,
LVCMOS
w/ pull down
Standard General Purpose IOs.
Available only in 18-bit color mode, and set by MODE_SEL or configuration register.
SeeTable 9
Leave open if unused
Shared with G1, G0, R1 and R0.
GPO_REG
[8:4]
1, 30, 45, 18, O, LVCMOS
19
w/ pull down
General Purpose Outputs and set by configuration register. See Table 9
Shared with I2S_CLK, I2S_WC, I2S_DA, I2S_DB or B1, B0.
INTB_IN
4
16
Input,
LVCMOS w/
pull-down
Interrupt Input
Shared with BISTC
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
Pin Name
Pin #
I/O, Type
Description
Optional Parallel Interface
PDB
59
I, LVCMOS Power-down Mode Input Pin
w/ pull-down PDB = H, device is enabled (normal operation)
Refer to ”Power Up Requirements and PDB Pin” in the Applications Information Section.
PDB = L, device is powered down.
When the device is in the POWER DOWN state, the LVCMOS Outputs are in TRI-STATE,
the PLL is shutdown and IDD is minimized. .
OEN
31
Input,
Output Enable Pin.
LVCMOS w/ See Table 3
pull-down
OSS_SEL
46
Input,
Output Sleep State Select Pin.
LVCMOS w/ See Table 3
pull-down
MODE_SEL
15
I, Analog
Device Configuration Select. See Table 4
IDx
56
I, Analog
I2C Serial Control Bus Device ID Address Select
External pull-up to VDD33 is required under all conditions, DO NOT FLOAT.
Connect to external pull-up and pull-down resistor to create a voltage divider.
See Figure 19
SCL
3
I/O,
LVCMOS
Open Drain
I2C Clock Input / Output Interface
Must have an external pull-up to VDD33, DO NOT FLOAT.
SDA
2
I/O,
LVCMOS
Open Drain
I2C Data Input / Output Interface
Must have an external pull-up to VDD33, DO NOT FLOAT.
BISTEN
44
I, LVCMOS BIST Enable Pin.
w/ pull-down 0: BIST Mode is disabled.
1: BIST Mode is enabled.
BISTC
16
I, LVCMOS BIST Clock Select.
w/ pull-down Shared with INTB_IN
0: PCLK; 1: 33 MHz
LOCK
32
O, LVCMOS LOCK Status Output Pin
w/ pull down 0: PLL is unlocked, ROUT[23:0]/RGB[7:0], I2S[2:0], HS, VS, DE and PCLK output states
are controlled by OEN. May be used as Link Status or Display Enable
1: PLL is Locked, outputs are active
PASS
42
O, LVCMOS PASS Output Pin
w/ pull down 0: One or more errors were detected in the received payload
1: ERROR FREE Transmission
Leave Open if unused. Route to test point (pad) recommended
Recommended pull-up: 4.7kΩ.
Recommended pull-up: 4.7kΩ.
Status
FPD-Link III Serial Interface
RIN+
49
I, LVDS
True Input.
The interconnection should be AC Coupled to this pin with a 0.1 μF capacitor.
RIN-
50
I, LVDS
Inverting Input.
The interconnection should be AC Coupled to this pin with a 0.1 μF capacitor.
CMLOUTP
52
O, LVDS
True CML Output
Monitor point for equalized differential signal
CMLOUTN
53
O, LVDS
Inverting CML Output
Monitor point for equalized differential signal
CMF
51
Analog
Common Mode Filter. Connect 0.1 μF capacitor to GND
Copyright © 1999-2012, Texas Instruments Incorporated
5
DS90UB926Q
Pin Name
Pin #
I/O, Type
Description
Power and Ground
VDD33_A,
VDD33_B
48, 29
Power
Power to on-chip regulator 3.0 V – 3.6 V. Requires 4.7 uF to GND at each VDD pin.
VDDIO
13, 24, 38
Power
LVCMOS I/O Power 1.8 V ±5% OR 3.0 V – 3.6 V. Requires 4.7 uF to GND at each VDDIO
pin.
GND
DAP
Ground
DAP is the large metal contact at the bottom side, located at the center of the LLP
package. Connect to the ground plane (GND) with at least 9 vias.
Regulator Capacitor
CAPR12,
CAPP12,
CAPI2S
55, 57, 58
CAP
Decoupling capacitor connection for on-chip regulator. Requires a 4.7uF to GND at each
CAP pin.
CAPL12
4
CAP
Decoupling capacitor connection for on-chip regulator. Requires two 4.7uF to GND at this
CAP pin.
Others
NC
RES[1:0]
54
NC
43.47
GND
No connect. This pin may be left open or tied to any level.
Reserved. Tie to Ground.
The VDD (VDD33 and VDDIO) supply ramp should be faster than 1.5 ms with a monotonic rise.
Block Diagram
30143428
Ordering Information
PART NUMBER
PACKAGE DESCRIPTION
QUANTITY
SPEC
PACKAGE ID
DS90UB926QSQE
60-pin LLP, 9.0 X 9.0 X 0.8 mm, 0.5 mm pitch
250
NOPB
SQA60B
DS90UB926QSQ
60-pin LLP, 9.0 X 9.0 X 0.8 mm, 0.5 mm pitch
1000
NOPB
SQA60B
DS90UB926QSQX
60-pin LLP, 9.0 X 9.0 X 0.8 mm, 0.5 mm pitch
2500
NOPB
SQA60B
Note: Automotive Grade (Q) product incorporates enhanced manufacturing and support processes for the automotive market,
including defect detection methodologies. Reliability qualification is compliant with the requirements and temperature grades
defined in the AEC Q100 standard. Automotive Grade products are identified with the letter Q. For more information go to
http://www.ti.com/automotive.
6
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for
availability and specifications.
Supply Voltage – VDD33
−0.3V to +4.0V
Supply Voltage – VDDIO
−0.3V to +4.0V
−0.3V to (VDDIO + 0.3V)
LVCMOS I/O Voltage
Deserializer Input Voltage
Junction Temperature
Storage Temperature
60 LLP Package
Maximum Power Dissipation Capacity at 25°C
Derate above 25°C
−0.3V to +2.75V
+150°C
−65°C to +150°C
1/ θJA°C/W
θJA
31 °C/W
θJC
2.4 °C/W
ESD Rating (IEC, powered-up only), RD = 330Ω, CS = 150pF
≥±15 kV
≥±8 kV
Air Discharge (RIN+, RIN−)
Contact Discharge (RIN+, RIN−)
ESD Rating (ISO10605), RD = 330Ω, CS = 150pF
≥±15 kV
≥±8 kV
Air Discharge (RIN+, RIN−)
Contact Discharge(RIN+, RIN−)
ESD Rating (ISO10605), RD = 2kΩ, CS = 150 & 330pF
≥±15 kV
≥±8 kV
≥±8 kV
Air Discharge (RIN+, RIN−)
Contact Discharge (RIN+, RIN−)
ESD Rating (HBM)
≥±1.25 kV
≥±250 V
ESD Rating (CDM)
ESD Rating (MM)
For soldering specifications:
see product folder at www.ti.com and
www.ti.com/lit/an/snoa549c/snoa549c.pdf
Recommended Operating Conditions
Supply Voltage (VDD33)
Min
3.0
Nom
3.3
Max
3.6
Units
V
LVCMOS Supply Voltage (VDDIO)
3.0
3.3
3.6
V
OR
LVCMOS Supply Voltage (VDDIO)
1.71
1.8
1.89
V
−40
5
+25
+105
85
100
°C
MHz
mVP-P
Operating Free Air
Temperature (TA)
PCLK Frequency
Supply Noise (Note 7)
Copyright © 1999-2012, Texas Instruments Incorporated
7
DS90UB926Q
DC Electrical Characteristics
Over recommended operating supply and temperature ranges unless otherwise specified. (Note 2, Note 3, Note 4)
Symbol
Parameter
Conditions
Pin/Freq.
Min
Typ
Max
Units
VDDIO
V
LVCMOS I/O DC SPECIFICATIONS
VIH
High Level Input Voltage
VDDIO = 3.0 to 3.6V
VIL
Low Level Input Voltage
VDDIO = 3.0 to 3.6V
IIN
Input Current
VIN = 0V or VDDIO = 3.0 to 3.6V
−10
VDDIO = 3.0 to 3.6V
VIH
High Level Input Voltage
VDDIO = 1.71 to 1.89V
VDDIO = 3.0 to 3.6V
VIL
IIN
VOH
VOL
IOS
IOZ
8
Low Level Input Voltage
Input Current
VDDIO = 1.71 to 1.89V
VIN = 0V or
VDDIO
VDDIO = 3.0
to 3.6V
2.0
GND
PDB
OEN,
OSS_SEL,
BISTEN,
BISTC /
INTB_IN,
GPIO[3:0]
0.8
V
+10
μA
2.0
VDDIO
V
0.65*
VDDIO
VDDIO
V
GND
0.8
V
GND
0.35*
VDDIO
V
±1
−10
±1
+10
μA
VDDIO = 1.7
to 1.89V
−10
±1
+10
μA
VDDIO = 3.0
to 3.6V
2.4
VDDIO
V
VDDIO0.45
VDDIO
V
GND
0.4
V
GND
0.35
V
ROUT[23:0],
HS, VS, DE,
IOH = −4mA
High Level Output Voltage
VDDIO = 1.7 PCLK,
LOCK,
to 1.89V
PASS,
VDDIO = 3.0
MCLK,
to 3.6V
I2S_CLK,
IOL = +4mA
Low Level Output Voltage
VDDIO = 1.7 I2S_WC,
to 1.89V
I2S_DA,
Output Short Circuit Current VOUT = 0V
I2S_DB,
GPO_REG
TRI-STATE® Output Current VOUT = 0V or VDDIO, PDB = L
[8:4]
−60
−10
mA
+10
μA
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
Symbol
Parameter
Conditions
Pin/Freq.
Min
Typ
Max
Units
+50
mV
FPD-LINK III CML RECEIVER INPUT DC SPECIFICATIONS
VTH
Differential Threshold High
Voltage
VTL
Differential Threshold Low
Voltage
VCM
Differential Common-mode
Voltage
RT
Internal Termination Resistor
- Differential
VCM = 2.5V
(Internal VBIAS)
−50
mV
RIN+, RIN1.8
80
100
V
120
Ω
CML MONITOR DRIVER OUTPUT DC SPECIFICATIONS
VODp-p
Differential Output Voltage
CMLOUTP,
CMLOUTN
RL = 100Ω
360
mVp-p
SUPPLY CURRENT
IDD1
IDDIO1
IDD2
IDDIO2
CL = 12pF,
Checker Board
Pattern
Figure 1
VDD33= 3.6V VDD33
125
145
mA
Supply Current
(includes load current)
f = 85MHz
VDDIO= 3.6V
110
118
mA
60
75
mA
CL = 4pF
Checker Board
Pattern,
Figure 1
VDD33 = 3.6V VDD33
125
145
mA
Supply Current
(includes load current)
f = 85MHz
VDDIO = 3.6V
75
85
mA
50
65
mA
VDD33 = 3.6V VDD33
90
115
mA
VDDIO = 3.6V
3
5
mA
2
3
mA
2
10
mA
0.05
10
mA
0.05
10
mA
IDDS
IDDIOS
Supply Current Sleep Mode
IDDZ
IDDIOZ
Supply Current Power Down
Copyright © 1999-2012, Texas Instruments Incorporated
Without Input
Serial Stream
PDB = L, All
LVCMOS
inputs are
floating or tied
to GND
VDDIO =
1.89V
VDDIO =
1.89V
VDDIO =
1.89V
VDDIO
VDDIO
VDDIO
VDD33 = 3.6V VDD33
VDDIO = 3.6V
VDDIO =
1.89V
VDDIO
9
DS90UB926Q
AC Electrical Characteristics
Over recommended operating supply and temperature ranges unless otherwise specified.(Note 2, Note 3, Note 4)
Symbol
Parameter
Conditions
Pin/Freq.
Min
Typ
Max
Units
GPIO BIT RATE
Forward Channel Bit Rate
BR
Back Channel Bit Rate
(Note 8, Note 9)
f=5–
85MHz,
GPIO[3:0]
0.25*f
Mbps
>50
>75
kbps
0.3
0.4
UI
200
300
mV
CML MONITOR DRIVER OUTPUT AC SPECIFICATIONS
EW
EH
Differential Output Eye Opening
RL = 100Ω,
Width
Jitter Freq >f / 40
(Note 6)
Figure 2 (Note 8, Note 9)
Differential Output Eye Height
CMLOUTP,
CMLOUTN,
f = 85MHz
SWITCHING CHARACTERISTICS
tRCP
PCLK Output Period
tRDC
PCLK Output Duty Cycle
tCLH
LVCMOS Low-to-High
Transition Time
Figure 3
tCHL
tROS
tROH
tXZR
tDDLT
tDD
tDCCJ
10
LVCMOS High-to-Low
Transition Time
Figure 3
tRCP = tTCP
VDDIO = 3.0 – 3.6V,
CL = 12pF
VDDIO = 1.71 - 1.89V,
CL = 12pF
VDDIO = 3.0 – 3.6V,
CL = 12pF
VDDIO = 1.71 - 1.89V,
CL = 12pF
Data Valid after PCLK – Hold
Time
SSCG = OFF
Figure 6
VDDIO = 1.71 - 1.89V,
CL = 12pF
Lock Time
Figure 5 (Note 8, Note 9)
VDDIO = 3.0 – 3.6V,
CL = 12pF
ROUT[23:0],
HS, VS, DE,
PCLK,
LOCK,
PASS,
MCLK,
I2S_CLK,
I2S_WC,
I2S_DA,
I2S_DB
VDDIO = 3.0 – 3.6V,
CL = 12pF
OEN = L, OSS_SEL = H
SSCG = OFF
Delay – Latency
(Note 8, Note 9)
Cycle-to-Cycle Jitter
(Note 8, Note 9)
11.76
T
200
ns
45
50
55
%
2
3
ns
2
3
ns
2
3
ns
2
3
ns
VDDIO = 1.71 - 1.89V,
CL = 12pF
Data Valid before PCLK – Setup
Time
SSCG = OFF
Figure 6
Active to OFF Delay
Figure 5 (Note 8, Note 9)
PCLK
SSCG = OFF
2.2
ns
2.2
ns
3.0
ns
3.0
ns
ROUT[23:0]
10
ns
HS, VS, DE,
PCLK,
LOCK, PASS
15
ns
MCLK,
I2S_CLK,
I2S_WC,
I2S_DA,
I2S_DB
60
ns
f = 5 – 85MHz
5
f = 5 – 85MHz
147*T
40
ms
ns
f = 5 – <15
MHz
0.5
ns
f = 15 – 85
MHz
0.2
ns
I2S_CLK = 1
- 12.28MHz
+/-2
ns
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
Symbol
tONS
tONH
tSES
tSEH
Parameter
Data Valid After OEN = H
SetupTime
Figure 7 (Note 8, Note 9)
Data Tri-State After OEN = L
SetupTime
Figure 7 (Note 8, Note 9)
Conditions
Pin/Freq.
Min
Typ
Max
Units
VDDIO = 1.71 - 1.89V,
CL = 12pF
50
ns
VDDIO = 3.0 – 3.6V,
CL = 12pF
50
ns
50
ns
50
ns
5
ns
5
ns
5
ns
5
ns
VDDIO = 1.71 - 1.89V,
CL = 12pF
VDDIO = 3.0 – 3.6V,
CL = 12pF
VDDIO = 1.71 - 1.89V,
Data Tri-State after OSS_ SEL
CL = 12pF
= H, Setup Time
VDDIO = 3.0 – 3.6V,
Figure 7 (Note 8, Note 9)
CL = 12pF
ROUT[23:0],
HS, VS, DE,
PCLK,
MCLK,
I2S_CLK,
I2S_WC,
I2S_DA,
I2S_DB
VDDIO = 1.71 - 1.89V,
Data to Low after OSS_SEL = L
CL = 12pF
Setup Time
VDDIO = 3.0 – 3.6V,
Figure 7 (Note 8, Note 9)
CL = 12pF
BIST Mode
tPASS
BIST PASS Valid Time
BISTEN = H
Figure 8 (Note 8, Note 9)
800
ns
PASS
SSCG Mode
fDEV
Spread Spectrum Clocking
Deviation Frequency
fMOD
Spread Spectrum Clocking
Modulation Frequency
Copyright © 1999-2012, Texas Instruments Incorporated
Figure 12
Tables 1, 2
(Note 8, Note 9)
f = 85MHz,
SSCG = ON
±0.5
±2.5
%
8
100
kHz
11
DS90UB926Q
Recommended Timing for the Serial Control Bus
Over 3.3V supply and temperature ranges unless otherwise specified.
Symbol
fSCL
tLOW
tHIGH
Parameter
SCL Clock Frequency
SCL Low Period
SCL High Period
Max
Units
Standard Mode
Conditions
Min
0
Typ
100
kHz
Fast Mode
0
400
kHz
Standard Mode
4.7
us
Fast Mode
1.3
us
Standard Mode
4.0
us
Fast Mode
0.6
us
Hold time for a start or a
repeated start condition
Figure 9
Standard Mode
4.0
us
Fast Mode
0.6
us
Set Up time for a start or a
repeated start condition
Figure 9
Standard Mode
4.7
us
Fast Mode
0.6
us
Data Hold Time
Figure 9
Standard Mode
0
3.45
us
Fast Mode
0
0.9
us
Data Set Up Time
Figure 9
Standard Mode
250
ns
Fast Mode
100
ns
tSU;STO
Set Up Time for STOP
Condition, Figure 9
Standard Mode
4.0
us
Fast Mode
0.6
us
tBUF
Bus Free Time between STOP Standard Mode
and START,
Fast Mode
Figure 9
4.7
us
1.3
us
tHD;STA
tSU:STA
tHD;DAT
tSU;DAT
tr
tf
SCL & SDA Rise Time,
Figure 9
Standard Mode
1000
ns
Fast Mode
300
ns
SCL & SDA Fall Time,
Figure 9
Standard Mode
300
ns
Fast mode
300
ns
Max
Units
0.7*
VDD33
VDD33
V
GND
0.3*
VDD33
V
DC and AC Serial Control Bus Characteristics
Over 3.3V supply and temperature ranges unless otherwise specified. (Note 2, Note 3, Note 4)
Symbol
12
Parameter
Conditions
VIH
Input High Level
SDA and SCL
VIL
Input Low Level Voltage
SDA and SCL
VHY
Input Hysteresis
SDA, IOL = 1.25mA
Iin
SDA or SCL, Vin = VDD33 or GND
SDA RiseTime – READ
tF
SDA Fall Time – READ
tSU;DAT
tHD;DAT
tSP
Input Filter
Cin
Input Capacitance
Typ
>50
VOL
tR
Min
mV
0
0.36
V
-10
+10
µA
SDA, RPU = 10kΩ, Cb ≤ 400pF, Figure 9
430
ns
20
ns
Set Up Time — READ
Figure 9
560
ns
Hold Up Time — READ
Figure 9
615
ns
50
ns
SDA or SCL
<5
pF
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
Note 1: “Absolute Maximum Ratings” indicate limits beyond which damage to the device may occur, including inoperability and degradation of device reliability
and/or performance. Functional operation of the device and/or non-degradation at the Absolute Maximum Ratings or other conditions beyond those indicated in
the Recommended Operating Conditions is not implied. The Recommended Operating Conditions indicate conditions at which the device is functional and the
device should not be operated beyond such conditions.
Note 2: The Electrical Characteristics tables list guaranteed specifications under the listed Recommended Operating Conditions except as otherwise modified or
specified by the Electrical Characteristics Conditions and/or Notes. Typical specifications are estimations only and are not guaranteed.
Note 3: Typical values represent most likely parametric norms at VDD = 3.3V, Ta = +25 degC, and at the Recommended Operation Conditions at the time of
product characterization and are not guaranteed.
Note 4: Current into device pins is defined as positive. Current out of a device pin is defined as negative. Voltages are referenced to ground except VOD and
ΔVOD, which are differential voltages.
Note 5: tDDLT is the time required by the device to obtain lock when exiting power-down state with an active serial stream.
Note 6: UI – Unit Interval is equivalent to one serialized data bit width (1UI = 1 / 35*PCLK). The UI scales with PCLK frequency.
Note 7: Supply noise testing was done with minimum capacitors on the PCB. A sinusoidal signal is AC coupled to the VDD33 and VDDIOsupplies with amplitude =
100 mVp-p measured at the device VDD33 and VDDIO pins. Bit error rate testing of input to the Ser and output of the Des with 10 meter cable shows no error when
the noise frequency on the Ser is less than 50MHz. The Des on the other hand shows no error when the noise frequency is less than 50 MHz.
Note 8: Specification is guaranteed by characterization and is not tested in production.
Note 9: Specification is guaranteed by design and is not tested in production.
Copyright © 1999-2012, Texas Instruments Incorporated
13
DS90UB926Q
AC Timing Diagrams and Test Circuits
30143446
FIGURE 1. Checker Board Data Pattern
30143474
FIGURE 2. CML Output Driver
30143430
FIGURE 3. LVCMOS Transition Times
30143447
FIGURE 4. Delay - Latency
14
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
30143461
FIGURE 5. PLL Lock Times and PDB TRI-STATE Delay
30143449
FIGURE 6. Output Data Valid (Setup and Hold) Times with SSCG = Off
Copyright © 1999-2012, Texas Instruments Incorporated
15
DS90UB926Q
30143450
FIGURE 7. Output State (Setup and Hold) Times
30143451
FIGURE 8. BIST PASS Waveform
16
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
30143436
FIGURE 9. Serial Control Bus Timing Diagram
Copyright © 1999-2012, Texas Instruments Incorporated
17
DS90UB926Q
Functional Description
The DS90UB926Q deserializer receives a 35-bits symbol over a single serial FPD-Link III pair operating upto 2.975 Gbps application
payload. The serial stream contains an embedded clock, video control signals and the DC-balanced video data and audio data
which enhance signal quality to support AC coupling.
The DS90UB926Q deserializer attains lock to a data stream without the use of a separate reference clock source, which greatly
simplifies system complexity and overall cost. The deserializer also synchronizes to the serializer regardless of the data pattern,
delivering true automatic “plug and lock” performance. It can lock to the incoming serial stream without the need of special training
patterns or sync characters. The deserializer recovers the clock and data by extracting the embedded clock information, validating
then deserializing the incoming data stream. The recovered parallel LVCMOS video bus is then provided to the display. The
deserializer is intended for use with the DS90UB925Q serializer, but is also backward compatible with DS90UR905Q or
DS90UR907Q FPD-Link II serializer.
HIGH SPEED FORWARD CHANNEL DATA TRANSFER
The High Speed Forward Channel (HS_FC) is composed of 35 bits of data containing DIN[23:0] or RGB[7:0] or YUV data, sync
signals, I2C, and I2S audio transmitted from Serializer to Deserializer. Figure 10 illustrates the serial stream per PCLK cycle. This
data payload is optimized for signal transmission over an AC coupled link. Data is randomized, balanced and scrambled.
30143437
FIGURE 10. FPD-Link III Serial Stream
The device supports clocks in the range of 5 MHz to 85 MHz. The application payload rate is 2.975 Gbps maximum (175 Mbps
minimum) with the actual line rate of 2.975 Gbps maximum and 525 Mbps Minimum.
LOW SPEED BACK CHANNEL DATA TRANSFER
The Low-Speed Backward Channel (LS_BC) of the DS90UB926Q provides bidirectional communication between the display and
host processor. The information is carried back from the Deserializer to the Serializer per serial symbol. The back channel control
data is transferred over the single serial link along with the high-speed forward data, DC balance coding and embedded clock
information. This architecture provides a backward path across the serial link together with a high speed forward channel. The back
channel contains the I2C, CRC and 4 bits of standard GPIO information with 10 Mbps line rate.
BACKWARD COMPATIBLE MODE
The DS90UB926Q is also backward compatible to DS90UR905Q and DS90UR907Q FPD Link II serializers at 15 - 65 MHz pixel
clock frequencies. It receives 28-bits of data over a single serial FPD-Link II pair operating at the line rate of 420 Mbps to 1.82
Gbps. This backward compatible mode is provided through the MODE_SEL pin (Table 4) or the configuration register (Table 9).
Note: In this mode, the minimum PCLK frequency is 15 MHz.
18
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
INPUT EQUALIZATION GAIN
FPD-Link III input adaptive equalizer provides compensation for transmission medium losses and reduces the medium-induced
deterministic jitter. It equalizes up to 10m STP cables with 3 connection breaks at maximum serialized stream payload rate of 2.975
Gbps.
COMMON MODE FILTER PIN (CMF)
The deserializer provides access to the center tap of the internal termination. A capacitor must be placed on this pin for additional
common-mode filtering of the differential pair. This can be useful in high noise environments for additional noise rejection capability.
A 0.1 μF capacitor has to be connected to this pin to Ground.
VIDEO CONTROL SIGNAL FILTER
When operating the devices in Normal Mode, the Video Control Signals (DE, HS, VS) have the following restrictions:
• Normal Mode with Control Signal Filter Enabled: DE and HS — Only 2 transitions per 130 clock cycles are transmitted, the
transition pulse must be 3 PCLK or longer.
• Normal Mode with Control Signal Filter Disabled: DE and HS — Only 2 transitions per 130 clock cycles are transmitted, no
restriction on minimum transition pulse.
• VS — Only 1 transition per 130 clock cycles are transmitted, minimum pulse width is 130 clock cycles.
Video Control Signals are defined as low frequency signals with limited transitions. Glitches of a control signal can cause a visual
display error. This feature allows for the chipset to validate and filter out any high frequency noise on the control signals. See
Figure 11.
30143402
FIGURE 11. Video Control Signal Filter Waveform
EMI REDUCTION FEATURES
Spread Spectrum Clock Generation (SSCG)
The DS90UB926Q provides an internally generated spread spectrum clock (SSCG) to modulate its outputs. Both clock and data
outputs are modulated. This will aid to lower system EMI. Output SSCG deviations to ±2.5% (5% total) at up to 100 kHz modulations
are available. This feature may be controlled by register. See Table 1, Table 2, and Table 9.
30143465
FIGURE 12. SSCG Waveform
Copyright © 1999-2012, Texas Instruments Incorporated
19
DS90UB926Q
TABLE 1. SSCG Configuration
LFMODE = L (15 - 85 MHz)
SSCG Configuration (0x2C) LFMODE = L (15 - 85MHz)
Spread Spectrum Output
SSC[2]
SSC[1]
SSC[0]
Fdev (%)
Fmod (kHz)
L
L
L
±0.9
PCLK / 2168
L
L
H
±1.2
L
H
L
±1.9
L
H
H
±2.5
H
L
L
±0.7
H
L
H
±1.3
H
H
L
±2.0
H
H
H
±2.5
PCLK / 1300
TABLE 2. SSCG Configuration
LFMODE = H (5 - <15 MHz)
SSCG Configuration (0x2C) LFMODE = H (5 - <15 MHz)
Spread Spectrum Output
SSC[2]
SSC[1]
SSC[0]
Fdev (%)
Fmod (kHz)
L
L
L
±0.5
PCLK / 628
L
L
H
±1.3
L
H
L
±1.8
L
H
H
±2.5
H
L
L
±0.7
H
L
H
±1.2
H
H
L
±2.0
H
H
H
±2.5
PCLK / 388
Enhanced Progressive Turn-On (EPTO)
The deserializer LVCMOS parallel outputs timing are delayed. Groups of 8-bit R, G and B outputs switch in a different time. This
minimizes the number of outputs switching simultaneously and helps to reduce supply noise. In addition it spreads the noise
spectrum out reducing overall EMI.
LVCMOS VDDIO Option
The deserializer parallel bus can operate with 1.8 V or 3.3 V levels (VDDIO) for target (Display) compatibility. The 1.8 V levels will
offer a lower noise (EMI) and also a system power savings.
POWER DOWN (PDB)
The Serializer has a PDB input pin to ENABLE or POWER DOWN the device. This pin can be controlled by the host or through
the VDDIO, where VDDIO = 3.0V to 3.6V or VDD33. To save power disable the link when the display is not needed (PDB = LOW).
When the pin is driven by the host, make sure to release it after VDD33 and VDDIO have reached final levels; no external components
are required. In the case of driven by the VDDIO = 3.0V to 3.6V or VDD33 directly, a 10 kohm resistor to the VDDIO = 3.0V to 3.6V or
VDD33 , and a >10uF capacitor to the ground are required (See Figure 22 Typical Connection Diagram).
STOP STREAM SLEEP
The deserializer enters a low power SLEEP state when the input serial stream is stopped. A STOP condition is detected when the
embedded clock bits are not present. When the serial stream starts again, the deserializer will then lock to the incoming signal and
recover the data. Note – in STOP STREAM SLEEP, the Serial Control Bus Registers values are retained.
SERIAL LINK FAULT DETECT
The serial link fault detection is able to detect any of following seven (7) conditions
1) cable open
2) “+” to “-“ short
3) “+” short to GND
4) “-“ short to GND
5) “+” short to battery
6) “-“ short to battery
7) Cable is linked incorrectly
If any one of the fault conditions occurs, The Link Detect Status is 0 (cable is not detected) on the Serial Control Bus Register bit
0 of address 0x1C Table 9. The link errors can be monitored though Link Error Count of the Serial Control Bus Register bit [4:0] of
address 0x41 Table 9.
20
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
OSCILLATOR OUTPUT
The deserializer provides an optional PCLK output when the input clock (serial stream) has been lost. This is based on an internal
oscillator. The frequency of the oscillator may be selected. This feature is controlled by register Address 0x02, bit 5 (OSC Clock
Enable). SeeTable 9.
PIXEL CLOCK EDGE SELECT (RFB)
The RFB determines the edge that the data is strobed on. If RFB is High (‘1’), output data is strobed on the Rising edge of the
PCLK. If RFB is Low (‘0’), data is strobed on the Falling edge of the PCLK. This allows for inter-operability with downstream devices.
The deserializer output does not need to use the same edge as the Ser input. This feature may be controlled by register. See
Table 9.
CLOCK-DATA RECOVERY STATUS FLAG (LOCK), OUTPUT ENABLE (OEN) AND OUTPUT STATE SELECT (OSS_SEL)
When PDB is driven HIGH, the CDR PLL begins locking to the serial input and LOCK is TRI-STATE or LOW (depending on the
value of the OEN setting). After the DS90UB926Q completes its lock sequence to the input serial data, the LOCK output is driven
HIGH, indicating valid data and clock recovered from the serial input is available on the parallel bus and PCLK outputs. The State
of the outputs are based on the OEN and OSS_SEL setting (Table 3) or register bit (Table 9). See Figure 7.
TABLE 3. Output States
Inputs
Outputs
Serial
input
PDB
OEN
OSS_SE Lock
L
Pass
Data, GPIO, I2S
CLK
X
0
X
X
Z
Z
Z
Z
X
1
0
0
L or H
L
L
L
X
1
0
1
L or H
Z
Z
Z
Static
1
1
0
L
L
L
L/OSC (Register bit
enable)
Static
1
1
1
L
Previous Status
L
L
Active
1
1
0
H
L
L
L
Active
1
1
1
H
Valid
Valid
Valid
LOW FREQUENCY OPTIMIZATION (LFMODE)
The LFMODE is set via register (Table 9) or MODE_SEL Pin 24 (Table 4). It controls the operating frequency of the deserializer.
If LFMODE is Low (default), the PCLK frequency is between 15 MHz and 85 MHz. If LFMODE is High, the PCLK frequency is
between 5 MHz and <15 MHz. Please note when the device LFMODE is changed, a PDB reset is required.
INTERRUPT PIN — FUNCTIONAL DESCRIPTION AND USAGE (INTB)
1. On DS90UB925, set register 0xC6[5] = 1 and 0xC6[0] = 1
2. DS90UB926Q deserializer INTB_IN (pin 16) is set LOW by some downstream device.
3. DS90UB925Q serializer pulls INTB (pin 31) LOW. The signal is active low, so a LOW indicates an interrupt condition.
4. External controller detects INTB = LOW; to determine interrupt source, read ISR register .
5. A read to ISR will clear the interrupt at the DS90UB925, releasing INTB.
6. The external controller typically must then access the remote device to determine downstream interrupt source and clear the
interrupt driving INTB_IN. This would be when the downstream device releases the INTB_IN (pin 16) on the DS90UB926Q.
The system is now ready to return to step (1) at next falling edge of INTB_IN.
Copyright © 1999-2012, Texas Instruments Incorporated
21
DS90UB926Q
CONFIGURATION SELECT (MODE_SEL)
Configuration of the device may be done via the MODE_SEL input pin, or via the configuration register bit. A pull-up resistor and
a pull-down resistor of suggested values may be used to set the voltage ratio of the MODE_SEL input (VR4) and VDD33 to select
one of the other 10 possible selected modes. See Figure 13 and Table 4.
30143441
FIGURE 13. MODE_SEL Connection Diagram
TABLE 4. Configuration Select (MODE_SEL)
#
Ideal Ratio
VR4/VDD33
Ideal VR4
(V)
Suggested
Resistor R3
kΩ (1% tol)
Suggested
Resistor R4
kΩ (1% tol)
LFMODE
Repeater
Backward
Compatible
I2S Channel
B
(18–bit
Mode)
1
0
0
Open
40.2 or Any
L
L
L
L
2
0.121
0.399
294
40.2
L
L
L
H
3
0.152
0.502
280
49.9
L
H
L
L
4
0.242
0.799
240
76.8
L
H
L
H
5
0.311
1.026
226
102
H
L
L
L
6
0.402
1.327
196
130
H
L
L
H
7
0.492
1.624
169
165
H
H
L
L
8
0.583
1.924
137
191
H
H
L
H
9
0.629
2.076
124
210
L
L
H
L
LFMODE: L = 15 – 85 MHz (Default); H = 5 – <15 MHz
Repeater: L = Repeater Off (Default); H = Repeater On
Backward Compatible: L = Backward Compatible Off (Default); H = Backward Compatible On to 905/907 (15 - 65MHz)
I2S Channel B: L = I2S Channel B Off, Normal 24-bit RGB Mode (Default); H = I2S Channel B On, 18-bit RGB Mode with I2S_DB
Enabled.
I2S RECEIVING
In normal 24-bit RGB operation mode, the DS90UB926Q provides up to 3-bit of I2S. They are I2S_CLK, I2S_WC and I2S_DA, as
well as the Master I2S Clock (MCLK). The audio is received through the forward video frame, or can be configured to receive during
video blanking periods. A jitter cleaning feature reduces I2S_CLK output jitter to +/- 2ns.
I2S Jitter Cleaning
The DS90UB926Q features a standalone PLL to clean the I2S data jitter supporting high end car audio systems. If I2S CLK
frequency is less than 1MHz, this feature has to be disabled through the register bit I2S Control (0x2B) in Table 9.
Secondary I2S Channel
In 18-bit RGB operation mode, the secondary I2S data (I2S_DB) can be used as the additional I2S audio channel in additional to
the 3–bit of I2S. The I2S_DB is synchronized to the I2S_CLK. To enable this synchronization feature on this bit, set the MODE_SEL
(Table 4) or program through the register bit (Table 9).
MCLK
The deserializer has an I2S Master Clock Output. It supports x1, x2, or x4 of I2S CLK Frequency. When the I2S PLL is disabled,
the MCLK output is off. below covers the range of I2S sample rates and MCLK frequencies.
By default, all the MCLK output frequencies are x2 of the I2S CLK frequencies. The MCLK frequencies can also be enabled through
the register bit [7:4] (I2S MCLK Output) of 0x3A shown in Table 9. To select desired MCLK frequency, write bit 7 (0x3A) = 1, then
write to bit [6:4] accordingly.
22
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
TABLE 5. Audio Interface Frequencies
Sample Rate
(kHz)
I2S Data Word Size
(bits)
I2S CLK
(MHz)
MCLK Output
(MHz)
Bit [6:4]
(Address 0x3A)
32
16
1.024
x1 of I2S CLK
000
x2 of I2S CLK
001
x4 of I2S CLK
010
x1 of I2S CLK
000
x2 of I2S CLK
001
x4 of I2S CLK
010
x1 of I2S CLK
000
x2 of I2S CLK
001
x4 of I2S CLK
010
x1 of I2S CLK
001
x2 of I2S CLK
010
x4 of I2S CLK
011
x1 of I2S CLK
010
x2 of I2S CLK
011
x4 of I2S CLK
100
x1 of I2S CLK
000
x2 of I2S CLK
001
x4 of I2S CLK
010
x1 of I2S CLK
001
x2 of I2S CLK
010
x4 of I2S CLK
011
x1 of I2S CLK
001
x2 of I2S CLK
010
x4 of I2S CLK
011
x1 of I2S CLK
010
x2 of I2S CLK
011
x4 of I2S CLK
100
x1 of I2S CLK
011
x2 of I2S CLK
100
x4 of I2S CLK
101
x1 of I2S CLK
001
x2 of I2S CLK
010
x4 of I2S CLK
011
x1 of I2S CLK
001
x2 of I2S CLK
010
x4 of I2S CLK
011
x1 of I2S CLK
001
x2 of I2S CLK
010
x4 of I2S CLK
011
x1 of I2S CLK
010
x2 of I2S CLK
011
x4 of I2S CLK
100
x1 of I2S CLK
011
x2 of I2S CLK
100
x4 of I2S CLK
110
44.1
48
96
192
32
44.1
48
96
192
32
44.1
48
96
192
16
16
16
16
24
24
24
24
24
32
32
32
32
32
Copyright © 1999-2012, Texas Instruments Incorporated
1.411
1.536
3.072
6.144
1.536
2.117
2.304
4.608
9.216
2.048
2.822
3.072
6.144
12.288
23
DS90UB926Q
GPIO[3:0] and GPO_REG[8:4]
In 18-bit RGB operation mode, the optional R[1:0] and G[1:0] of the DS90UB926Q can be used as the general purpose IOs GPIO
[3:0] in either forward channel (Outputs) or back channel (Inputs) application.
GPIO[3:0] Enable Sequence
See Table 6 for the GPIO enable sequencing.
Step 1: Enable the 18-bit mode either through the configuration register bit Table 9 on DS90UB925Q only. DS90UB926Q is
automatically configured as in the 18-bit mode.
Step 2: To enable GPIO3 forward channel, write 0x03 to address 0x0F on DS90UB925Q, then write 0x05 to address 0x1F on
DS90UB926Q.
TABLE 6. GPIO Enable Sequencing Table
#
Description
Device
Forward Channel
1
Enable 18-bit
mode
DS90UB925Q
0x12 = 0x04
0x12 = 0x04
DS90UB926Q
Auto Load from DS90UB925Q
Auto Load from DS90UB925Q
GPIO3
DS90UB925Q
0x0F = 0x03
0x0F = 0x05
DS90UB926Q
0x1F = 0x05
0x1F = 0x03
DS90UB925Q
0x0E = 0x30
0x0E = 0x50
DS90UB926Q
0x1E = 0x50
0x1E = 0x30
DS90UB925Q
0x0E = 0x03
0x0E = 0x05
DS90UB926Q
0x1E = 0x05
0x0E = 0x05
DS90UB925Q
0x0D = 0x93
0x0D = 0x95
DS90UB926Q
0x1D = 0x95
0x1D = 0x93
2
3
GPIO2
4
GPIO1
5
GPIO0
Back Channel
GPO_REG[8:4] Enable Sequence
GPO_REG[8:4] are the outputs only pins. They must be programmed through the local register bits. See Table 7 for the GPO_REG
enable sequencing.
Step 1: Enable the 18-bit mode either through the configuration register bit on DS90UB925Q only. DS90UB926Q is automatically
configured as in the 18-bit mode.
Step 2: To enable GPO_REG8 outputs an “1” , write 0x90 to address 0x21 on DS90UB926Q..
TABLE 7. GPO_REG Enable Sequencing Table
#
Description
Device
Local Access
1
Enable 18-bit mode
DS90UB926Q
0x12 = 0x04
(on DS90UB925Q)
2
GPO_REG8
DS90UB926Q
0x21 = 0x90
“1”
0x21 = 0x10
“0”
0x21 = 0x09
“1”
0x21 = 0x01
“0”
0x20 = 0x90
“1”
0x20 = 0x10
“0”
0x20 = 0x09
“1”
0x20 = 0x01
“0”
0x1F = 0x90
“1”
0x1F = 0x10
“0”
3
4
5
6
24
GPO_REG7
GPO_REG6
GPO_REG5
GPO_REG4
DS90UB926Q
DS90UB926Q
DS90UB926Q
DS90UB926Q
Local Output Value
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
REPEATER APPLICATION
The DS90UB925Q and DS90UB926Q can be configured to extend data transmission over multiple links to multiple display devices.
Setting the devices into repeater mode provides a mechanism for transmitting to all receivers in the system.
Repeater Configuration
In a repeater application, In this document, the DS90UB925Q is referred to as the Transmitter or transmit port (TX), and the
DS90UB926Q is referred to as the Receiver (RX). Figure 14 shows the maximum configuration supported for Repeater implementations using the DS90UB925Q (TX) and DS90UB926Q (RX). Two levels of Repeaters are supported with a maximum of three
Transmitters per Receiver.
30143410
FIGURE 14. Maximum Repeater Application
Copyright © 1999-2012, Texas Instruments Incorporated
25
DS90UB926Q
In a repeater application, the I2C interface at each TX and RX may be configured to transparently pass I2C communications
upstream or downstream to any I2C device within the system. This includes a mechanism for assigning alternate IDs (Slave Aliases)
to downstream devices in the case of duplicate addresses.
At each repeater node, the parallel LVCMOS interface fans out to up to three serializer devices, providing parallel RGB video data,
HS/VS/DE control signals and, optionally, packetized audio data (transported during video blanking intervals). Alternatively, the
I2S audio interface may be used to transport digital audio data between receiver and transmitters in place of packetized audio. All
audio and video data is transmitted at the output of the Receiver and is received by the Transmitter..
Figure 15 provides more detailed block diagram of a 1:2 repeater configuration.
30143432
FIGURE 15. 1:2 Repeater Configuration
26
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
Repeater Connections
The Repeater requires the following connections between the Receiver and each Transmitter Figure 16.
1) Video Data – Connect PCLK, RGB and control signals (DE, VS, HS).
2) I2C – Connect SCL and SDA signals. Both signals should be pulled up to VDD33 with 4.7 kΩ resistors.
3) Audio – Connect I2S_CLK, I2S_WC, and I2S_DA signals.
4) IDx pin – Each Transmitter and Receiver must have an unique I2C address.
5) MODE_SEL pin – All Transmitter and Receiver must be set into the Repeater Mode.
6) Interrupt pin– Connect DS90UB926Q INTB_IN pin to DS90UB925Q INTB pin. The signal must be pulled up to VDDIO.
30143442
FIGURE 16. Repeater Connection Diagram
Copyright © 1999-2012, Texas Instruments Incorporated
27
DS90UB926Q
BUILT IN SELF TEST (BIST)
An optional At-Speed Built In Self Test (BIST) feature supports the testing of the high speed serial link and the low- speed back
channel. This is useful in the prototype stage, equipment production, in-system test and also for system diagnostics.
Note: BIST is not available in backwards compatible mode.
BIST Configuration and Status
The BIST mode is enabled at the deseralizer by the Pin select (Pin 44 BISTEN and Pin 16 BISTC) or configuration register(Table
9) through the deserializer. When LFMODE = 0, the pin based configuration defaults to external PCLK or 33 MHz internal Oscillator
clock (OSC) frequency. In the absence of PCLK, the user can select the desired OSC frequency (default 33 MHz or 25MHz) through
the register bit. When LFMODE = 1, the pin based configuration defaults to external PCLK or 12.5MHz MHz internal Oscillator
clock (OSC) frequency.
When BISTEN of the deserializer is high, the BIST mode enable information is sent to the serializer through the Back Channel.
The serializer outputs a test pattern and drives the link at speed. The deserializer detects the test pattern and monitors it for errors.
The PASS output pin toggles to flag any payloads that are received with 1 to 35 bit errors.
The BIST status is monitored real time on PASS pin. The result of the test is held on the PASS output until reset (new BIST test
or Power Down). A high on PASS indicates NO ERRORS were detected. A Low on PASS indicates one or more errors were
detected. The duration of the test is controlled by the pulse width applied to the deserializer BISTEN pin. This BIST feature also
contains a Link Error Count and a Lock Status. If the connection of the serial link is broken, then the link error count is shown in
the register. When the PLL of the deserializer is locked or unlocked, the lock status can be read in the register. See Table 9.
Sample BIST Sequence
See Figure 17 for the BIST mode flow diagram.
Step 1: For the DS90UB925Q and DS90UB926Q FPD-Link III chipset, BIST Mode is enabled via the BISTEN pin of DS90UB926Q
FPD-Link III deserializer. The desired clock source is selected through BISTC pin.
Step 2: The DS90UB925Q serializer is woken up through the back channel if it is not already on. The all zero pattern on the data
pins is sent through the FPD-Link III to the deserializer. Once the serializer and the deserializer are in BIST mode and the deserializer
acquires Lock, the PASS pin of the deserializer goes high and BIST starts checking the data stream. If an error in the payload (1
to 35) is detected, the PASS pin will switch low for one half of the clock period. During the BIST test, the PASS output can be
monitored and counted to determine the payload error rate.
Step 3: To Stop the BIST mode, the deserializer BISTEN pin is set Low. The deserializer stops checking the data. The final test
result is held on the PASS pin. If the test ran error free, the PASS output will be High. If there was one or more errors detected,
the PASS output will be Low. The PASS output state is held until a new BIST is run, the device is RESET, or Powered Down. The
BIST duration is user controlled by the duration of the BISTEN signal.
Step 4: The Link returns to normal operation after the deserializer BISTEN pin is low. Figure 18 shows the waveform diagram of
a typical BIST test for two cases. Case 1 is error free, and Case 2 shows one with multiple errors. In most cases it is difficult to
generate errors due to the robustness of the link (differential data transmission etc.), thus they may be introduced by greatly
extending the cable length, faulting the interconnect, reducing signal condition enhancements (Rx Equalization).
30143443
FIGURE 17. BIST Mode Flow Diagram
28
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
Forward Channel and Back Channel Error Checking
While in BIST mode, the serializer stops sampling RGB input pins and switches over to an internal test pattern. The internal allzeroes pattern goes through scrambler, dc-balancing etc. and goes over the serial link to the deserializer. The deserializer on
locking to the serial stream compares the recovered serial stream with all-zeroes and records any errors in status registers and
dynamically indicates the status on PASS pin.
The back-channel data is checked for CRC errors once the serializer locks onto back-channel serial stream as indicated by link
detect status (register bit 0x0C[0]). The CRC errors are recorded in an 8-bit register. The register is cleared when the serializer
enters the BIST mode. As soon as the serializer exits BIST mode, the functional mode CRC register starts recording the CRC
errors. The BIST mode CRC error register is active in BIST mode only and keeps the record of last BIST run until cleared or enters
BIST mode again.
30143464
FIGURE 18. BIST Waveforms
Copyright © 1999-2012, Texas Instruments Incorporated
29
DS90UB926Q
Serial Control Bus
The DS90UB926Q is configured by the use of a serial control bus that is I2C protocol compatible. . Multiple deserializer devices
may share the serial control bus since 16 device addresses are supported. Device address is set via R1 and R2 values on IDx pin.
See Figure 19 below.
The serial control bus consists of two signals and a configuration pin. The SCL is a Serial Bus Clock Input / Output. The SDA is
the Serial Bus Data Input / Output signal. Both SCL and SDA signals require an external pull-up resistor to VDD33. For most applications a 4.7 k pull-up resistor to VDD33 may be used. The resistor value may be adjusted for capacitive loading and data rate
requirements. The signals are either pulled High, or driven Low.
30143401
FIGURE 19. Serial Control Bus Connection
The configuration pin is the IDx pin. This pin sets one of 16 possible device addresses. A pull-up resistor and a pull-down resistor
of suggested values may be used to set the voltage ratio of the IDx input (VR2) and VDD33 to select one of the other 16 possible
addresses. See Table 8.
TABLE 8. Serial Control Bus Addresses for IDx
#
30
Ideal Ratio
VR2 / VDD33
Ideal VR2
(V)
Suggested
Resistor R1 kΩ
(1% tol)
Suggested
Resistor R2 kΩ
(1% tol)
Address 7'b
Address 8'b
Appended
1
0
0
Open
40.2 or Any
0x2C
0x58
2
0.121
0.399
294
40.2
0x2D
0x5A
3
0.152
0.502
280
49.9
0x2E
0x5C
4
0.182
0.601
270
60.4
0x2F
0x5E
5
0.212
0.700
267
71.5
0x30
0x60
6
0.242
0.799
240
76.8
0x31
0x62
7
0.273
0.901
243
90.9
0x32
0x64
8
0.310
1.023
226
102
0x33
0x66
9
0.356
1.175
210
115
0x34
0x68
10
0.402
1.327
196
130
0x35
0x6A
11
0.447
1.475
182
147
0x36
0x6C
12
0.492
1.624
169
165
0x37
0x6E
13
0.538
1.775
154
180
0x38
0x70
14
0.583
1.924
137
191
0x39
0x72
15
0.629
2.076
124
210
0x3A
0x74
16
0.727
2.399
90.9
243
0x3B
0x76
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
TABLE 9. Serial Control Bus Registers
ADD
(dec)
0
1
ADD Register
(hex) Name
0x00 I2C Device ID
0x01 Reset
Bit(s)
Register
Type
Default Function
(hex)
7:1
RW
Device ID
7–bit address of Deserializer
See Table 4
0
RW
ID Setting
I2C ID Setting
1: Register I2C Device ID (Overrides IDx pin)
0: Device ID is from IDx pin
7
RW
0x04
Remote
Remote Auto Power Down
Auto Power 1: Power down when no forward channel link is
Down
detected
0: Do not power down when no forward channel link is
detected
6:3
2
0x02 Configuration
[0]
Descriptions
Reserved
2
RW
BC Enable
Back channel enable
1: Enable
0: Disable
1
RW
Digital
RESET1
Reset the entire digital block including registers
This bit is self-clearing.
1: Reset
0: Normal operation
0
RW
Digital
RESET0
Reset the entire digital block except registers
This bit is self-clearing
1: Reset
0: Normal operation
7
RW
Output
Enable
LVCMOS Output Enable.
1: Enable
0: Disable. Tri-state Outputs
6
RW
OEN and
OSS_SEL
Override
Overrides Output Enable Pin and Output State pin
1: Enable override
0: Disable - no override
5
RW
OSC Clock OSC Clock Output Enable
Enable
If loss of lock OSC clock is output onto PCLK
0: Disable
1: Enable
4
RW
Output
Sleep State
Select
(OSS_SEL)
OSS Select to Control Output State during Lock Low
Period
1: Enable
0: Disable
3
RW
Backward
Compatible
Mode
Override
Mode_Sel Backward compatible Mode Override
Enable.
1: Use register bit "reg_02[2]" to set BC Mode
0: Use MODE_SEL option.
2
RW
Backward
Compatible
Mode
Select
Backward Compatible Mode Select to DS90UR905Q
and DS90UR907Q. If Reg_02[3] = 1
1: Backward Compatible is on
0: Backward Compatible is off
1
RW
LFMODE
Pin
Override
LFMODE Pin Override Enable
1: Use register bit "reg_02[0]" to set LFMODE
0: Use LFMODE Pin
0
RW
LFMODE
Low Frequency Mode Select
1: PCLK = 5 - <15 MHz
0: PCLK = 15 - 85 MHz
Copyright © 1999-2012, Texas Instruments Incorporated
0x00
31
DS90UB926Q
ADD
(dec)
3
ADD Register
(hex) Name
0x03 Configuration
[1]
Bit(s)
Register
Type
7
6
Default Function
(hex)
0xF0
Reserved
RW
CRC
Generator
Enable
4
RW
Filter
Enable
HS, VS, DE two clock filter When enabled, pulses less
than two full PCLK cycles on the DE, HS, and VS inputs
will be rejected
1: Filtering enable
0: Filtering disable
3
RW
I2C Passthrough
I2C Pass-Through Mode
1: Pass-Through Enabled
0: Pass-Through Disabled
2
RW
Auto ACK
ACK Select
1: Auto ACK enable
0: Self ACK
0
RW
RRFB
Pixel Clock Edge Select
1: Parallel Interface Data is strobed on the Rising Clock
Edge.
0: Parallel Interface Data is strobed on the Falling
Clock Edge.
7:1
RW
BCC
Watchdog
Timer
The watchdog timer allows termination of a control
channel transaction, if it fails to complete within a
programmed amount of time. This field sets the
Bidirectional Control Channel Watchdog Timeout
value in units of 2 milliseconds.
This field should not be set to 0
0
RW
BCC
Watchdog
Timer
Disable
Disable Bidirectional Control Channel Watchdog Timer
1: Disables BCC Watchdog Timer operation
0: Enables BCC Watchdog Timer operation"
7
RW
6:4
RW
I2C SDA
Hold Time
Internal I2C SDA Hold Time
It configures the amount of internal hold time provided
for the SDA input relative to the SCL input. Units are
50 ns.
3:0
RW
I2C Filter
Depth
I2C Glitch Filter Depth
It configures the maximum width of glitch pulses on the
SCL and SDA inputs that will be rejected. Units are 5
ns.
5
5
32
0x04 BCC
Watchdog
Control
0x05 I2C Control
[1]
CRC Generator Enable (Back Channel)
1: Enable
0: Disable
Reserved
1
4
Descriptions
Reserved
0xFE
0x2E
I2C Pass
I2C Pass-Through All Transactions
Through All 1: Enabled
0: Disabled
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
ADD
(dec)
6
ADD Register
(hex) Name
0x06 I2C Control
[2]
Bit(s)
Register
Type
7
R
6
RW
Default Function
(hex)
0x00
Forward
Channel
Sequence
Error
Control Channel Sequence Error Detected It indicates
a sequence error has been detected in forward control
channel. It this bit is set, an error may have occurred in
the control channel operation.
Clear
Sequence
Error
It clears the Sequence Error Detect bit
This bit is not self-clearing.
5
7
8
0x07 Remote
Device ID
0x08 SlaveID[0]
Descriptions
Reserved
4:3
RW
SDA Output SDA Output Delay
Delay
This field configures output delay on the SDA output.
Setting this value will increase output delay in units of
50 ns. Nominal output delay values for SCL to SDA are:
00 : 250ns
01: 300ns
10: 350ns
11: 400ns
2
RW
Local Write Disable Remote Writes to Local Registers through
Serializer (Does not affect remote access to I2C slaves
at Deserializer)
1: Stop remote write to local device registers
0: remote write to local device registers
1
RW
I2C Bus
Timer
Speed
Speed up I2C Bus Watchdog Timer
1: Timer expires after approximately 50 ms
0: Timer expires after approximately 1s
0
RW
I2C Bus
Timer
Disable
Disable I2C Bus Timer When the I2C Timer may be
used to detect when the I2C bus is free or hung up
following an invalid termination of a transaction. If SDA
is high and no signalling occurs for approximately 1 s,
the I2C bus is assumed to be free. If SDA is low and
no signaling occurs, the device will attempt to clear the
bus by driving 9 clocks on SCL
7:1
RW
Remote ID
Remote ID
Configures the I2C Slave ID of the remote Serializer. A
value of 0 in this field disables I2C access to remote
Serializer. This field is automatically configured via the
Serializer Forward Channel. Software may overwrite
this value, but should also set the FREEZE DEVICE ID
bit to prevent overwriting by the Forward Channel.
0
RW
Freeze
Device ID
Freeze Serializer Device ID
1: Prevent auto-loading of the Serializer Device ID from
the Forward Channel. The ID will be frozen at the value
written.
0: Update
7:1
RW
Target
Slave
Device ID0
7-bit Remote Slave Device ID 0
Configures the physical I2C address of the remote I2C
Slave device attached to the remote Serializer. If an
I2C transaction is addressed to the Slave Alias ID0, the
transaction will be remapped to this address before
passing the transaction across the Bidirectional
Control Channel to the Serializer.
0
Copyright © 1999-2012, Texas Instruments Incorporated
0x18
0x00
Reserved
33
DS90UB926Q
ADD
(dec)
ADD Register
(hex) Name
Bit(s)
Register
Type
RW
0x00
Target
Slave
Device ID1
RW
0x00
Target
Slave
Device ID2
RW
0x00
Target
Slave
Device ID3
RW
0x00
Target
Slave
Device ID4
9
0x09 SlaveID[1]
7:1
10
0x0A SlaveID[2]
7:1
11
0x0B SlaveID[3]
7:1
12
0x0C SlaveID[4]
7:1
Default Function
(hex)
0
0x0E SlaveID[6]
7:1
0
34
7-bit Remote Slave Device ID 4
Configures the physical I2C address of the remote I2C
Slave device attached to the remote Serializer. If an
I2C transaction is addressed to the Slave Alias ID4, the
transaction will be remapped to this address before
passing the transaction across the Bidirectional
Control Channel to the Serializer.
Reserved
RW
0x00
Target
Slave
Device ID5
0
14
7-bit Remote Slave Device ID 3
Configures the physical I2C address of the remote I2C
Slave device attached to the remote Serializer. If an
I2C transaction is addressed to the Slave Alias ID3, the
transaction will be remapped to this address before
passing the transaction across the Bidirectional
Control Channel to the Serializer.
Reserved
0
7:1
7-bit Remote Slave Device ID 2
Configures the physical I2C address of the remote I2C
Slave device attached to the remote Serializer. If an
I2C transaction is addressed to the Slave Alias ID2, the
transaction will be remapped to this address before
passing the transaction across the Bidirectional
Control Channel to the Serializer.
Reserved
0
0x0D SlaveID[5]
7-bit Remote Slave Device ID 1
Configures the physical I2C address of the remote I2C
Slave device attached to the remote Serializer. If an
I2C transaction is addressed to the Slave Alias ID1, the
transaction will be remapped to this address before
passing the transaction across the Bidirectional
Control Channel to the Serializer.
Reserved
0
13
Descriptions
7-bit Remote Slave Device ID 5
Configures the physical I2C address of the remote I2C
Slave device attached to the remote Serializer. If an
I2C transaction is addressed to the Slave Alias ID5, the
transaction will be remapped to this address before
passing the transaction across the Bidirectional
Control Channel to the Serializer.
Reserved
RW
0x00
Target
Slave
Device ID6
7-bit Remote Slave Device ID 6
Configures the physical I2C address of the remote I2C
Slave device attached to the remote Serializer. If an
I2C transaction is addressed to the Slave Alias ID6, the
transaction will be remapped to this address before
passing the transaction across the Bidirectional
Control Channel to the Serializer.
Reserved
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
ADD
(dec)
ADD Register
(hex) Name
Bit(s)
Register
Type
RW
0x00
Target
Slave
Device ID7
RW
0x00
ID[0] Match 7-bit Remote Slave Device Alias ID 0
Configures the decoder for detecting transactions
designated for an I2C Slave device attached to the
remote Serializer. The transaction will be remapped to
the address specified in the Slave ID0 register.
A value of 0 in this field disables access to the remote
I2C Slave.
15
0x0F SlaveID[7]
7:1
16
0x10 SlaveAlias[0]
7:1
Default Function
(hex)
0
Descriptions
7-bit Remote Slave Device ID 7
Configures the physical I2C address of the remote I2C
Slave device attached to the remote Serializer. If an
I2C transaction is addressed to the Slave Alias ID7, the
transaction will be remapped to this address before
passing the transaction across the Bidirectional
Control Channel to the Serializer.
Reserved
0
Copyright © 1999-2012, Texas Instruments Incorporated
Reserved
35
DS90UB926Q
ADD
(dec)
ADD Register
(hex) Name
Bit(s)
Register
Type
RW
0x00
ID[1] Match 7-bit Remote Slave Device Alias ID 1
Configures the decoder for detecting transactions
designated for an I2C Slave device attached to the
remote Serializer. The transaction will be remapped to
the address specified in the Slave ID1 register.
A value of 0 in this field disables access to the remote
I2C Slave.
RW
0x00
ID[2] Match 7-bit Remote Slave Device Alias ID 2
Configures the decoder for detecting transactions
designated for an I2C Slave device attached to the
remote Serializer. The transaction will be remapped to
the address specified in the Slave ID2 register.
A value of 0 in this field disables access to the remote
I2C Slave.
RW
0x10
ID[3] Match 7-bit Remote Slave Device Alias ID 3
Configures the decoder for detecting transactions
designated for an I2C Slave device attached to the
remote Serializer. The transaction will be remapped to
the address specified in the Slave ID3 register.
A value of 0 in this field disables access to the remote
I2C Slave.
RW
0x00
ID[4] Match 7-bit Remote Slave Device Alias ID 4
Configures the decoder for detecting transactions
designated for an I2C Slave device attached to the
remote Serializer. The transaction will be remapped to
the address specified in the Slave ID4 register.
A value of 0 in this field disables access to the remote
I2C Slave.
17
0x11 SlaveAlias[1]
7:1
18
0x12 SlaveAlias[2]
7:1
19
0x13 SlaveAlias[3]
7:1
20
0x14 SlaveAlias[4]
7:1
Default Function
(hex)
0
Reserved
0
Reserved
0
Reserved
0
21
0x15 SlaveAlias[5]
7:1
Reserved
RW
0x00
0
22
36
0x16 SlaveAlias[6]
Descriptions
ID[5] Match 7-bit Remote Slave Device Alias ID 5
Configures the decoder for detecting transactions
designated for an I2C Slave device attached to the
remote Serializer. The transaction will be remapped to
the address specified in the Slave ID5 register.
A value of 0 in this field disables access to the remote
I2C Slave.
Reserved
7:1
RW
0
RW
0x00
ID[6] Match 7-bit Remote Slave Device Alias ID 6
Configures the decoder for detecting transactions
designated for an I2C Slave device attached to the
remote Serializer. The transaction will be remapped to
the address specified in the Slave ID6 register.
A value of 0 in this field disables access to the remote
I2C Slave.
Reserved
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
ADD
(dec)
ADD Register
(hex) Name
Bit(s)
Register
Type
RW
0x00
0x00
23
0x17 SlaveAlias[7]
7:1
28
0x1C General
Status
7:4
RW
3
R
Default Function
(hex)
ID[7] Match 7-bit Remote Slave Device Alias ID 7
Configures the decoder for detecting transactions
designated for an I2C Slave device attached to the
remote Serializer. The transaction will be remapped to
the address specified in the Slave ID7 register.
A value of 0 in this field disables access to the remote
I2C Slave.
0
Reserved
Reserved
I2S Locked I2S Lock Status
0: I2S PLL controller not locked
1: I2S PLL controller locked to input I2S clock
2
Reserved
1
0
29
0x1D GPIO0
Config
Descriptions
Reserved
R
Deserializer CDR, PLL's clock to recovered clock
frequency
1: Deserializer locked to recovered clock
0: Deserializer not locked
7:4
R
Rev-ID
Revision ID: 1010: Production Device
3
RW
GPIO0
Output
Value
Local GPIO Output Value
This value is output on the GPIO pin when the GPIO
function is enabled, the local GPIO direction is Output,
and remote GPIO control is disabled.
2
RW
GPIO0
Remote
Enable
Remote GPIO0 Control
1: Enable GPIO control from remote Serializer. The
GPIO pin will be an output, and the value is received
from the remote Deserializer.
0: Disable GPIO control from remote Serializer
1
RW
GPIO0
Direction
Local GPIO Direction
1: Input
0: Output
0
RW
GPIO0
Enable
GPIO Function Enable
1: Enable GPIO operation
0: Enable normal operation
Copyright © 1999-2012, Texas Instruments Incorporated
0xA0
Lock
37
DS90UB926Q
ADD
(dec)
30
31
ADD Register
(hex) Name
0x1E GPIO2 and
GPIO1
Config
0x1F GPO_REG4
and GPO3
Config
Bit(s)
Register
Type
7
RW
6
Default Function
(hex)
0x00
GPIO2
Output
Value
Local GPIO Output Value
This value is output on the GPIO when the GPIO
function is enabled, the local GPIO direction is Output,
and remote GPIO control is disabled.
RW
GPIO2
Remote
Enable
Remote GPIO2 Control
1: Enable GPIO control from remote Serializer. The
GPIO pin will be an output, and the value is received
from the remote Deserializer.
0: Disable GPIO control from remote Serializer.
5
RW
GPIO2
Direction
Local GPIO Direction
1: Input
0: Output
4
RW
GPIO2
Enable
GPIO Function Enable
1: Enable GPIO operation
0: Enable normal operation
3
RW
GPIO1
Output
Value
Local GPIO Output Value
This value is output on the GPIO when the GPIO
function is enabled, the local GPIO direction is Output,
and remote GPIO control is disabled.
2
RW
GPIO1
Remote
Enable
Remote GPIO1 Control
1: Enable GPIO control from remote Serializer. The
GPIO pin will be an output, and the value is received
from the remote Deserializer.
0: Disable GPIO control from remote Serializer.
1
RW
GPIO1
Direction
Local GPIO Direction
1: Input
0: Output
0
RW
GPIO1
Enable
GPIO Function Enable
1: Enable GPIO operation
0: Enable normal operation
7
RW
0x00
GPO_REG Local GPO_REG4 Output Value
4 Output
This value is output on the GPO when the GPO
Value
function is enabled, the local GPO direction is Output,
and remote GPO control is disabled.
6:5
38
Descriptions
Reserved
4
RW
GPO_REG GPO_REG4 Function Enable
4 Enable
1: Enable GPO operation
0: Enable normal operation
3
RW
GPIO3
Output
Value
Local GPIO Output Value This value is output on the
GPIO when the GPIO function is enabled, the local
GPIO direction is Output, and remote GPIO control is
disabled.
2
RW
GPIO3
Remote
Enable
Remote GPIO3 Control
1: Enable GPIO control from remote Serializer. The
GPIO pin will be an output, and the value is received
from the remote Deserializer.
0: Disable GPIO control from remote Serializer.
1
RW
GPIO3
Direction
Local GPIO Direction
1: Input
0: Output
0
RW
GPIO3
Enable
GPIO Function Enable
1: Enable GPIO operation
0: Enable normal operation
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
ADD
(dec)
32
ADD Register
(hex) Name
0x20 GPO_REG6
and
GPO_REG5
Config
Bit(s)
Register
Type
7
RW
Default Function
(hex)
0x00
6:5
0x21 GPO8 and
GPO7 Config
GPO_REG Local GPO_REG6 Output Value
6 Output
This value is output on the GPO when the GPO
Value
function is enabled, the local GPO direction is Output,
and remote GPO control is disabled.
Reserved
4
RW
GPO_REG GPO_REG6 Function Enable
6 Enable
1: Enable GPO operation
0: Enable normal operation
3
RW
GPO_REG Local GPO_REG5 Output Value
5 Output
This value is output on the GPO when the GPO
Value
function is enabled, the local GPO direction is Output,
and remote GPO control is disabled.
0
RW
GPO_REG GPO_REG5 Function Enable
5 Enable
1: Enable GPO operation
0: Enable normal operation
7
RW
2:1
33
Descriptions
Reserved
6:5
0x00
GPO_REG Local GPO_REG8 Output Value
8 Output
This value is output on the GPO when the GPO
Value
function is enabled, the local GPO direction is Output,
and remote GPO control is disabled.
Reserved
4
RW
GPO_REG GPO_REG8 Function Enable
8 Enable
1: Enable GPO operation
0: Enable normal operation
3
RW
GPO_REG Local GPO_REG7 Output Value
7 Output
This value is output on the GPO when the GPO
Value
function is enabled, the local GPO direction is Output,
and remote GPO control is disabled.
RW
GPO_REG GPO_REG7 Function Enable
7 Enable
1: Enable GPO operation
0: Enable normal operation
2:1
0
Reserved
Copyright © 1999-2012, Texas Instruments Incorporated
39
DS90UB926Q
40
ADD
(dec)
ADD Register
(hex) Name
Bit(s)
Register
Type
34
0x22 Data Path
Control
7
RW
6
Default Function
(hex)
0x00
Descriptions
Override
FC Config
1: Disable loading of this register from the forward
channel, keeping locally written values intact
0: Allow forward channel loading of this register
RW
Pass RGB
Setting this bit causes RGB data to be sent
independent of DE. This allows operation in systems
which may not use DE to frame video data or send
other data when DE is deasserted. Note that setting
this bit blocks packetized audio. This bit does not need
to be set in DS90UB925 or in Backward Compatibility
mode.
1: Pass RGB independent of DE
0: Normal operation
Note: this bit is automatically loaded from the remote
serializer unless bit 7 of this register is set.
5
RW
DE Polarity This bit indicates the polarity of the DE (Data Enable)
signal.
1: DE is inverted (active low, idle high)
0: DE is positive (active high, idle low)
Note: this bit is automatically loaded from the remote
serializer unless bit 7 of this register is set.
4
RW
I2S_Gen
This bit controls whether the Receiver outputs
packetized Auxiliary/Audio data on the RGB video
output pins.
1: Don't output packetized audio data on RGB video
output pins
0: Output packetized audio on RGB video output pins.
Note: this bit is automatically loaded from the remote
serializer unless bit 7 of this register is set.
3
RW
I2S
Channel B
Enable
Override
1: Set I2S Channel B Enable from reg_22[0]
0: Set I2S Channel B Enable from MODE_SEL pin
Note: this bit is automatically loaded from the remote
serializer unless bit 7 of this register is set.
2
RW
18-bit Video 1: Select 18-bit video mode
Select
0: Select 24-bit video mode
Note: this bit is automatically loaded from the remote
serializer unless bit 7 of this register is set.
1
RW
I2S
Transport
Select
1: Enable I2S Data Forward Channel Frame Transport
0: Enable I2S Data Island Transport
Note: this bit is automatically loaded from the remote
serializer unless bit 7 of this register is set.
0
RW
I2S
Channel B
Enable
I2S Channel B Enable
1: Enable I2S Channel B on B1 output
0: I2S Channel B disabled
Note: this bit is automatically loaded from the remote
serializer unless bit 7 of this register is set.
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
ADD
(dec)
ADD Register
(hex) Name
Bit(s)
Register
Type
35
0x23 General
Purpose
Control
7
RW
Default Function
(hex)
0x10
Rx RGB
Checksum
6:5
36
0x24 BIST Control
Descriptions
RX RGB Checksum Enable Setting this bit enables the
Receiver to validate a one-byte checksum following
each video line. Checksum failures are reported in the
STS register
Reserved
4
R
Mode_Sel
Mode Select is Done
3
R
LFMODE
Low Frequency Mode Status
2
R
Repeater
Repeater Mode Status
1
R
Backward
Backward Compatible Mode Status
0
R
I2S
Channel B
I2S Channel B Status
7:4
0x08
Reserved
3
RW
BIST Pin
Config
BIST Configured through Pin
1: BIST configured through pin
0: BIST configured through register bit
2:1
RW
BIST Clock BIST Clock Source
Source
00: External Pixel Clock
01: 33 MHz Oscillator
10: Reserved
11: 25 MHz Oscillator
0
RW
BIST
Enable
BIST Control
1: Enabled
0: Disabled
37
0x25 BIST Error
7:0
R
0x00
BIST Error
Count
BIST Error Count
38
0x26 SCL High
Time
7:0
RW
0x83
SCL High
Time
I2C Master SCL High Time
This field configures the high pulse width of the SCL
output when the Deserializer is the Master on the local
I2C bus. Units are 50 ns for the nominal oscillator clock
frequency. The default value is set to provide a
minimum 5us SCL high time with the internal oscillator
clock running at 26MHz rather than the nominal
20MHz.
39
0x27 SCL Low
Time
7:0
RW
0x84
SCL Low
Time
I2C SCL Low Time
This field configures the low pulse width of the SCL
output when the De-Serializer is the Master on the local
I2C bus. This value is also used as the SDA setup time
by the I2C Slave for providing data prior to releasing
SCL during accesses over the Bidirectional Control
Channel. Units are 50 ns for the nominal oscillator
clock frequency. The default value is set to provide a
minimum 5us SCL low time with the internal oscillator
clock running at 26MHz rather than the nominal
20MHz.
Copyright © 1999-2012, Texas Instruments Incorporated
41
DS90UB926Q
ADD
(dec)
41
42
ADD Register
(hex) Name
0x29 FRC Control
0x2A White
Balance
Control
Bit(s)
Register
Type
Default Function
(hex)
7
RW
6
RW
VS Polarity 0: Active High
1: Active Low
5
RW
HS Polarity 0: Active High
1: Active Low
4
RW
DE Polarity 0: Active High
1: Active Low
3
RW
FRC2
Enable
0: FRC2 Disable
1: FRC2 Enable
2
RW
FRC1
Enable
0: FRC1 Disable
1: FRC1 Enable
1
RW
Hi-FRC 2
Disable
0: Hi-FRC2 Enable
1: Hi-FRC2 Disable
0
RW
Hi-FRC 1
Disable
0: Hi-FRC1 Enable
1: Hi-FRC1 Disable
7:6
RW
Page
Setting
00: Configuration Registers
01: Red LUT
10: Green LUT
11: Blue LUT
5
RW
White
Balance
Enable
0: White Balance Disable
1: White Balance Enable
4
RW
LUT Reload 0: Reload Disable
Enable
1: Reload Enable
0x00
0x00
Timing
Mode
Select
3:0
43
0x2B I2S Control
7
42
Select display timing mode
0: DE only Mode
1: Sync Mode (VS,HS)
Reserved
RW
0x00
I2S PLL
6:1
0
Descriptions
I2S PLL Control
0: I2S PLL is on for I2S data jitter cleaning
1: I2S PLL is off. No jitter cleaning
Reserved
RW
I2S Clock
Edge
I2S Clock Edge Select
0: I2S Data is strobed on the Rising Clock Edge
1: I2S Data is strobed on the Falling Clock Edge
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
ADD
(dec)
44
58
ADD Register
(hex) Name
0x2C SSCG
Control
0x3A I2S MCLK
Output
Bit(s)
Register
Type
7:4
Default Function
(hex)
0x00
Reserved
3
RW
SSCG
Enable
Enable Spread Spectrum Clock Generator
0: Disable
1: Enable
2:0
RW
SSCG
Selection
SSCG Frequency Deviation:
When LFMODE = H
fdev fmod
000: +/- 0.7 CLK/628
001: +/- 1.3
010: +/- 1.8
011: +/- 2.5
100: +/- 0.7 CLK/388
101: +/- 1.2
110: +/- 2.0
111: +/- 2.5
When LFMODE = L
fdev fmod
000: +/- 0.9 CLK/2168
001: +/- 1.2
010: +/- 1.9
011: +/- 2.5
100: +/- 0.7 CLK/1300
101: +/- 1.3
110: +/- 2.0
111: +/- 2.5
7
RW
MCLK
Override
1: Override divider select for MCLK
0: No override for MCLK divider
6:4
RW
MCLK
Frequency
Slect
See Table 5
0x00
3:0
65
0x41 Link Error
Count
Descriptions
Reserved
7:5
0x03
Reserved
4
RW
Link Error
Count
Enable
Enable serial link data integrity error count
1: Enable error count
0: Disable
3:0
RW
Link Error
Count
Link error count threshold.
Counter is pixel clock based. clk0, clk1 and DCA are
monitored for link errors, if error count is enabled,
deserializer loose lock once error count reaches
threshold. If disabled deserilizer loose lock with one
error.
Copyright © 1999-2012, Texas Instruments Incorporated
43
DS90UB926Q
ADD
(dec)
68
ADD Register
(hex) Name
0x44 Equalization
Bit(s)
Register
Type
7:5
RW
Default Function
(hex)
0x60
EQ Stage 1 EQ select value.
Select
Used if adaptive EQ is bypassed.
000 Min EQ 1st Stage
001
010
011
100
101
110
111 Max EQ 1st Stage
4
86
0x56 CML Output
Reserved
3:1
RW
EQ Stage 2 EQ select value.
Select
Used if adaptive EQ is bypassed.
000 Min EQ 2nd Stage
001
010
011
100
101
110
111 Max EQ 2nd Stage
0
RW
Adaptive
EQ
7:4
3
2:0
44
Descriptions
0x08
RW
1: Disable adaptive EQ (to write EQ select values)
0: Enable adaptive EQ
Reserved
CMLOUT
+/- Enable
1: Disabled (Default)
0: Enabled
Reserved
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
ADD
(dec)
100
ADD Register
(hex) Name
0x64 Pattern
Generator
Control
Bit(s)
Register
Type
7:4
RW
Default Function
(hex)
0x10
Pattern
Generator
Select
3:1
0
Descriptions
Fixed Pattern Select
This field selects the pattern to output when in Fixed
Pattern Mode. Scaled patterns are evenly distributed
across the horizontal or vertical active regions. This
field is ignored when Auto-Scrolling Mode is enabled.
The following table shows the color selections in noninverted followed by inverted color mode
0000: Reserved 0001: White/Black
0010: Black/White
0011: Red/Cyan
0100: Green/Magenta
0101: Blue/Yellow
0110: Horizontally Scaled Black to White/White to
Black
0111: Horizontally Scaled Black to Red/Cyan to White
1000: Horizontally Scaled Black to Green/Magenta to
White
1001: Horizontally Scaled Black to Blue/Yellow to
White
1010: Vertically Scaled Black to White/White to Black
1011: Vertically Scaled Black to Red/Cyan to White
1100: Vertically Scaled Black to Green/Magenta to
White
1101: Vertically Scaled Black to Blue/Yellow to White
1110: Custom color (or its inversion) configured in
PGRS, PGGS, PGBS registers
1111: Reserved
Reserved
RW
Copyright © 1999-2012, Texas Instruments Incorporated
Pattern
Generator
Enable
Pattern Generator Enable
1: Enable Pattern Generator
0: Disable Pattern Generator
45
DS90UB926Q
ADD
(dec)
101
46
ADD Register
(hex) Name
0x65 Pattern
Generator
Configuration
Bit(s)
Register
Type
7:5
Default Function
(hex)
0x00
Descriptions
Reserved
4
RW
Pattern
Generator
18 Bits
18-bit Mode Select
1: Enable 18-bit color pattern generation. Scaled
patterns will have 64 levels of brightness and the R, G,
and B outputs use the six most significant color bits.
0: Enable 24-bit pattern generation. Scaled patterns
use 256 levels of brightness.
3
RW
Pattern
Generator
External
Clock
Select External Clock Source
1: Selects the external pixel clock when using internal
timing.
0: Selects the internal divided clock when using internal
timing
This bit has no effect in external timing mode
(PATGEN_TSEL = 0).
2
RW
Pattern
Generator
Timing
Select
Timing Select Control
1: The Pattern Generator creates its own video timing
as configured in the Pattern Generator Total Frame
Size, Active Frame Size. Horizontal Sync Width,
Vertical Sync Width, Horizontal Back Porch, Vertical
Back Porch, and Sync Configuration registers.
0: the Pattern Generator uses external video timing
from the pixel clock, Data Enable, Horizontal Sync, and
Vertical Sync signals.
1
RW
Pattern
Enable Inverted Color Patterns
Generator 1: Invert the color output.
Color Invert 0: Do not invert the color output.
0
RW
Pattern
Generator
Auto-Scroll
Enable
Auto-Scroll Enable:
1: The Pattern Generator will automatically move to the
next enabled pattern after the number of frames
specified in the Pattern Generator Frame Time (PGFT)
register.
0: The Pattern Generator retains the current pattern.
102
0x66 Pattern
Generator
Indirect
Address
7:0
RW
0x00
Indirect
Address
This 8-bit field sets the indirect address for accesses
to indirectly-mapped registers. It should be written prior
to reading or writing the Pattern Generator Indirect
Data register.
See AN-2198
103
0x67 Pattern
Generator
Indirect Data
7:0
RW
0x00
Indirect
Data
When writing to indirect registers, this register contains
the data to be written. When reading from indirect
registers, this register contains the read back value.
See AN-2198
240
0xF0 RX ID
7:0
R
0x5F
ID0
First byte ID code: ‘_’
241
0xF1
7:0
R
0x55
ID1
Second byte of ID code: ‘U’
242
0xF2
7:0
R
0x48
ID2
Third byte of ID code, Value will be either ‘B’.
243
0xF3
7:0
R
0x39
ID3
Fourth byte of ID code: ‘9’
244
0xF4
7:0
R
0x32
ID4
Fifth byte of ID code: '2'
245
0xF5
7:0
R
0x36
ID5
Sixth byte of ID code: '6'
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
Image Enhancement Features
Several image enhancement features are provided. White balance LUTs allow the user to define and target the color temperature
of the display. Adaptive Hi-FRC dithering enables the presentation of “true-color” images on an 18–bit color display.
WHITE BALANCE
The White Balance feature enables similar display appearance when using LCD’s from different vendors. It compensates for native
color temperature of the display, and adjusts relative intensities of R, G, B to maintain specified color temperature. Programmable
control registers are used to define the contents of three LUTs (8-bit color value for Red, Green and Blue) for the White Balance
Feature. The LUTs map input RGB values to new output RGB values. There are three LUTs, one LUT for each color. Each LUT
contains 256 entries, 8-bits per entry with a total size of 6144 bits (3 x 256 x 8). All entries are readable and writable. Calibrated
values are loaded into registers through the I2C interface (deserializer is a slave device). This feature may also be applied to lower
color depth applications such as 18–bit (666) and 16–bit (565). White balance is enabled and configured via serial control bus
register.
LUT contents
The user must define and load the contents of the LUT for each color (R,G,B). Regardless of the color depth being driven (888,
666, 656), the user must always provide contents for 3 complete LUTs - 256 colors x 8 bits x 3 tables. Unused bits - LSBs -shall
be set to “0” by the user.
When 24-bit (888) input data is being driven to a 24-bit display, each LUT (R, G and B) must contain 256 unique 8-bit entries. The
8-bit white balanced data is then available at the output of the DS90UB926Q deserailizer, and driven to the display.
When 18-bit (666) input data is being driven to an 18-bit display, the white balance feature may be used in one of two ways. First,
simply load each LUT with 256, 8-bit entries. Each 8-bit entry is a 6-bit value (6 MSBs) with the 2 LSBs set to “00”. Thus as total
of 64 unique 6-bit white balance output values are available for each color (R, G and B). The 6-bit white balanced data is available
at the output of the DS90UB926Q deserializer, and driven directly to the display.
Alternatively, with 6-bit input data the user may choose to load complete 8-bit values into each LUT. This mode of operation provides
the user with finer resolution at the LUT output to more closely achieve the desired white point of the calibrated display. Although
8-bit data is loaded, only 64 unique 8-bit white balance output values are available for each color (R, G and B). The result is 8-bit
white balanced data. Before driving to the output of the deserializer, the 8-bit data must be reduced to 6-bit with an FRC dithering
function. To operate in this mode, the user must configure the DS90UB926Q to enable the FRC2 function.
Examples of the three types of LUT configurations described are shown in Figure 20
Enabling white balance
The user must load all 3 LUTs prior to enabling the white balance feature. The following sequence must be followed by the user.
To initialize white balance after power-on (Table 10):
1) Load contents of all 3 LUTs . This requires a sequential loading of LUTs - first RED, second GREEN, third BLUE. 256, 8-bit
entries must be loaded to each LUT. Page registers must be set to select each LUT.
2) Enable white balance
By default, the LUT data may not be reloaded after initialization at power-on.
An option does exist to allow LUT reloading after power-on and initial LUT loading (as described above). This option may only be
used after enabling the white balance reload feature via the associated serial control bus register. In this mode the LUTs may be
reloaded by the master controller via I2C. This provides the user with the flexibility to refresh LUTs periodically , or upon system
requirements to change to a new set of LUT values. The host controller loads the updated LUT values via the serial bus interface.
There is no need to disable the white balance feature while reloading the LUT data. Refreshing the white balance to the new set
of LUT data will be seamless - no interruption of displayed data.
It is important to note that initial loading of LUT values requires that all 3 LUTs be loaded sequentially. When reloading, partial LUT
updates may be made.
Copyright © 1999-2012, Texas Instruments Incorporated
47
DS90UB926Q
30143472
FIGURE 20. White Balance LUT Configurations
TABLE 10. White Balance Register Table
PAG
E
ADD
(dec)
ADD
(hex)
0
42
0x2A
Register Name
White Balance
Control
Bit(s) Access Default
(hex)
7:6
RW
5
RW
4
RW
0x00
Function
Description
Page Setting
00: Configuration Registers
01: Red LUT
10: Green LUT
11: Blue LUT
White Balance
Enable
0: White Balance Disable
1: White Balance Enable
0: Reload Disable
1: Reload Enable
3:0
Reserved
1
0–
255
00 – FF White Balance
Red LUT
FF:0
RW
N/A
Red LUT
2
0–
255
00 – FF White Balance
Green LUT
FF:0
RW
N/A
Green LUT
3
0–
255
00 – FF White Balance
Blue LUT
FF:0
RW
N/A
Blue LUT
256 8–bit entries to be applied to the Red
subpixel data
256 8–bit entries to be applied to the
Green subpixel data
256 8–bit entries to be applied to the Blue
subpixel data
ADAPTIVE HI-FRC DITHERING
The Adaptive FRC Dithering Feature delivers product-differentiating image quality. It reduces 24-bit RGB (8 bits per subpixel) to
18-bit RGB (6 bits per sub-pixel), smoothing color gradients, and allowing the flexibility to use lower cost 18-bit displays. FRC
(Frame Rate Control) dithering is a method to emulate “missing” colors on a lower color depth LCD display by changing the pixel
color slightly with every frame. FRC is achieved by controlling on and off pixels over multiple frames (Temporal). Static dithering
regulates the number of on and off pixels in a small defined pixel group (Spatial). The FRC module includes both Temporal and
Spatial methods and also Hi-FRC. Conventional FRC can display only 16,194,277 colors with 6-bit RGB source. “Hi-FRC” enables
full (16,777,216) color on an 18-bit LCD panel. The “adaptive” FRC module also includes input pixel detection to apply specific
Spatial dithering methods for smoother gray level transitions. When enabled, the lower LSBs of each RGB output are not active;
only 18 bit data (6 bits per R,G and B) are driven to the display. This feature is enabled via serial control bus register.
Two FRC functional blocks are available, and may be independently enabled. FRC1 precedes the white balance LUT, and is
intended to be used when 24-bit data is being driven to an 18-bit display with a white balance LUT that is calibrated for an 18-bit
48
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
data source. The second FRC block, FRC2, follows the white balance block and is intended to be used when fine adjustment of
color temperature is required on an 18-bit color display, or when a 24-bit source drives an 18-bit display with a white balance LUT
calibrated for 24-bit source data.
For proper operation of the FRC dithering feature, the user must provide a description of the display timing control signals. The
timing mode, “sync mode” (HS, VS) or “DE only” must be specified, along with the active polarity of the timing control signals. All
this information is entered to DS90UB926Q control registers via the serial bus interface.
Adaptive Hi-FRC dithering consists of several components. Initially, the incoming 8-bit data is expanded to 9-bit data. This allows
the effective dithered result to support a total of 16.7 million colors. The incoming 9-bit data is evaluated, and one of four possible
algorithms is selected. The majority of incoming data sequences are supported by the default dithering algorithm. Certain incoming
data patterns (black/white pixel, full on/off sub-pixel) require special algorithms designed to eliminate visual artifacts associated
with these specific gray level transitions. Three algorithms are defined to support these critical transitions.
An example of the default dithering algorithm is illustrated in Figure 21. The “1” or “0” value shown in the table describes whether
the 6-bit value is increased by 1 (“1”) or left unchanged (“0”). In this case, the 3 truncated LSBs are “001”.
30143473
FIGURE 21. Default FRC Algorithm
See Table 11 for recommended FRC settings dependant on 18/24–bit source, 18/24–bit white balance LUT, and 18/24–bit display.
TABLE 11. Recommended FRC settings
Source
White Balance LUT
Display
FRC1
FRC2
24–bit
24–bit
24–bit
Disabled
Disabled
24–bit
24–bit
18–bit
Disabled
Enabled
24–bit
18–bit
18–bit
Enabled
Disabled
18–bit
24–bit
24–bit
Disabled
Disabled
18–bit
24–bit
18–bit
Disabled
Enabled
18–bit
18–bit
18–bit
Disabled
Disabled
Copyright © 1999-2012, Texas Instruments Incorporated
49
DS90UB926Q
Internal Pattern Generation
The DS90UB926Q serializer supports the internal pattern generation feature. It allows basic testing and debugging of an integrated
panel. The test patterns are simple and repetitive and allow for a quick visual verification of panel operation. As long as the device
is not in power down mode, the test pattern will be displayed even if no parallel input is applied. If no PCLK is received, the test
pattern can be configured to use a programmed oscillator frequency. For detailed information, refer to Application Note AN-2198.
Applications Information
DISPLAY APPLICATION
The DS90UB926Q, in conjunction with the DS90UB925Q, is intended for interface between a host (graphics processor) and a
Display. It supports an 24-bit color depth (RGB888) and high definition (720p) digital video format. It allows to receive a three 8-bit
RGB stream with a pixel rate up to 85 MHz together with three control bits (VS, HS and DE) and three I2S-bus audio stream with
an audio sampling rate up to 192 kHz.
The deserializer is expected to be located close to its target device. The interconnect between the deserializer and the target device
is typically in the 1 to 3 inch separation range. The input capacitance of the target device is expected to be in the 5 to 10 pF range.
Care should be taken on the PCLK output trace as this signal is edge sensitive and strobes the data. It is also assumed that the
fanout of the deserializer is up to three in the repeater mode. If additional loads need to be driven, a logic buffer or mux device is
recommended.
TYPICAL APPLICATION CONNECTION
Figure 22 shows a typical application of the DS90UB926Q deserializer for an 85 MHz 24-bit Color Display Application. inputs utilize
0.1 μF coupling capacitors to the line and the deserializer provides internal termination. Bypass capacitors are placed near the
power supply pins. At a minimum, seven 0.1 μF capacitors and two 4.7 μF capacitors should be used for local device bypassing.
Ferrite beads are placed on the power lines for effective noise suppression. Since the device in the Pin/STRAP mode, two 10 kΩ
pull-up resistors are used on the parallel output bus to select the desired device features.
The interface to the target display is with 3.3V LVCMOS levels, thus the VDDIO pins are connected to the 3.3 V rail. A delay cap is
placed on the PDB signal to delay the enabling of the device until power is stable.
50
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
30143444
FIGURE 22. Typical Connection Diagram
Copyright © 1999-2012, Texas Instruments Incorporated
51
DS90UB926Q
POWER UP REQUIREMENTS AND PDB PIN
The VDDs (VDD33 and VDDIO) supply ramp should be faster than 1.5 ms with a monotonic rise. A large capacitor on the PDB pin is
needed to ensure PDB arrives after all the VDDs have settled to the recommended operating voltage. When PDB pin is pulled to
VDDIO = 3.0V to 3.6V or VDD33, it is recommended to use a 10 kΩ pull-up and a >10 uF cap to GND to delay the PDB input signal.
All inputs must not be driven until VDD33 and VDDIO has reached its steady state value.
TRANSMISSION MEDIA
The DS90UB925Q and DS90UB926Q chipset is intended to be used in a point-to-point configuration through a shielded twisted
pair cable. The serializer and deserializer provide internal termination to minimize impedance discontinuities. The interconnect
(cable and connector) between the serializer and deserializer should have a differential impedance of 100 Ohms. The maximum
length of cable that can be used is dependant on the quality of the cable (gauge, impedance), connector, board (discontinuities,
power plane), the electrical environment (e.g. power stability, ground noise, input clock jitter, PCLK frequency, etc.) and the application environment.
The resulting signal quality at the receiving end of the transmission media may be assessed by monitoring the differential eye
opening of the serial data stream. The Receiver CML Monitor Driver Output Specifications define the acceptable data eye opening
width and eye opening height. A differential probe should be used to measure across the termination resistor at the CMLOUT+/pin Figure 2 .
PCB LAYOUT AND POWER SYSTEM CONSIDERATIONS
Circuit board layout and stack-up for the FPD-Link III devices should be designed to provide low-noise power feed to the device.
Good layout practice will also separate high frequency or high-level inputs and outputs to minimize unwanted stray noise pickup,
feedback and interference. Power system performance may be greatly improved by using thin dielectrics (2 to 4 mils) for power /
ground sandwiches. This arrangement provides plane capacitance for the PCB power system with low-inductance parasitics, which
has proven especially effective at high frequencies, and makes the value and placement of external bypass capacitors less critical.
External bypass capacitors should include both RF ceramic and tantalum electrolytic types. RF capacitors may use values in the
range of 0.01 uF to 0.1 uF. Tantalum capacitors may be in the 2.2 uF to 10 uF range. Voltage rating of the tantalum capacitors
should be at least 5X the power supply voltage being used.
Surface mount capacitors are recommended due to their smaller parasitics. When using multiple capacitors per supply pin, locate
the smaller value closer to the pin. A large bulk capacitor is recommend at the point of power entry. This is typically in the 50uF to
100uF range and will smooth low frequency switching noise. It is recommended to connect power and ground pins directly to the
power and ground planes with bypass capacitors connected to the plane with via on both ends of the capacitor. Connecting power
or ground pins to an external bypass capacitor will increase the inductance of the path.
A small body size X7R chip capacitor, such as 0603 or 0402, is recommended for external bypass. Its small body size reduces the
parasitic inductance of the capacitor. The user must pay attention to the resonance frequency of these external bypass capacitors,
usually in the range of 20-30 MHz. To provide effective bypassing, multiple capacitors are often used to achieve low impedance
between the supply rails over the frequency of interest. At high frequency, it is also a common practice to use two vias from power
and ground pins to the planes, reducing the impedance at high frequency.
Some devices provide separate power and ground pins for different portions of the circuit. This is done to isolate switching noise
effects between different sections of the circuit. Separate planes on the PCB are typically not required. Pin Description tables
typically provide guidance on which circuit blocks are connected to which power pin pairs. In some cases, an external filter may be
used to provide clean power to sensitive circuits such as PLLs.
Use at least a four layer board with a power and ground plane. Locate LVCMOS signals away from the CML lines to prevent coupling
from the LVCMOS lines to the CML lines. Closely-coupled differential lines of 100 Ohms are typically recommended for CML
interconnect. The closely coupled lines help to ensure that coupled noise will appear as common-mode and thus is rejected by the
receivers. The tightly coupled lines will also radiate less.
Information on the LLP style package is provided in TI Application Note: AN-1187.
CML INTERCONNECT GUIDELINES
See AN-1108 and AN-905 for full details.
• Use 100Ω coupled differential pairs
• Use the S/2S/3S rule in spacings
– S = space between the pair
– 2S = space between pairs
– 3S = space to LVCMOS signal
• Minimize the number of Vias
• Use differential connectors when operating above 500 Mbps line speed
• Maintain balance of the traces
• Minimize skew within the pair
Additional general guidance can be found in the LVDS Owner’s Manual - available in PDF format from the TI web site at:
www.ti.com/lvds
52
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
Revision
•
•
March 30, 2012
— Web release
July 19, 2012
— Converted to hybrid TI format
— Corrected typo in table “DC and AC Serial Control Bus Characteristics” from VDDIO to VDD33
— Added “Note: BIST is not available in backwards compatible mode.”
— Added Recommended FRC settings table
Copyright © 1999-2012, Texas Instruments Incorporated
53
DS90UB926Q
Physical Dimensions inches (millimeters) unless otherwise noted
60–pin LLP Package (9.0 mm X 9.0 mm X 0.8 mm, 0.5 mm pitch)
NS Package Number SQA60B
54
Copyright © 1999-2012, Texas Instruments Incorporated
DS90UB926Q
Notes
Copyright © 1999-2012, Texas Instruments Incorporated
55
Notes
Copyright © 1999-2012, Texas Instruments
Incorporated
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other
changes to its semiconductor products and services per JESD46C and to discontinue any product or service per JESD48B. Buyers should
obtain the latest relevant information before placing orders and should verify that such information is current and complete. All
semiconductor products (also referred to herein as “components”) are sold subject to TI’s terms and conditions of sale supplied at the time
of order acknowledgment.
TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms
and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary
to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily
performed.
TI assumes no liability for applications assistance or the design of Buyers’ products. Buyers are responsible for their products and
applications using TI components. To minimize the risks associated with Buyers’ products and applications, Buyers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or
other intellectual property right relating to any combination, machine, or process in which TI components or services are used. Information
published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or
endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the
third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration
and is accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such altered
documentation. Information of third parties may be subject to additional restrictions.
Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service
voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice.
TI is not responsible or liable for any such statements.
Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements
concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support
that may be provided by TI. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which
anticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause
harm and take appropriate remedial actions. Buyer will fully indemnify TI and its representatives against any damages arising out of the use
of any TI components in safety-critical applications.
In some cases, TI components may be promoted specifically to facilitate safety-related applications. With such components, TI’s goal is to
help enable customers to design and create their own end-product solutions that meet applicable functional safety standards and
requirements. Nonetheless, such components are subject to these terms.
No TI components are authorized for use in FDA Class III (or similar life-critical medical equipment) unless authorized officers of the parties
have executed a special agreement specifically governing such use.
Only those TI components which TI has specifically designated as military grade or “enhanced plastic” are designed and intended for use in
military/aerospace applications or environments. Buyer acknowledges and agrees that any military or aerospace use of TI components
which have not been so designated is solely at the Buyer's risk, and that Buyer is solely responsible for compliance with all legal and
regulatory requirements in connection with such use.
TI has specifically designated certain components which meet ISO/TS16949 requirements, mainly for automotive use. Components which
have not been so designated are neither designed nor intended for automotive use; and TI will not be responsible for any failure of such
components to meet such requirements.
Products
Applications
Audio
www.ti.com/audio
Automotive and Transportation www.ti.com/automotive
Amplifiers
amplifier.ti.com
Communications and Telecom www.ti.com/communications
Data Converters
dataconverter.ti.com
Computers and Peripherals
www.ti.com/computers
DLP® Products
www.dlp.com
Consumer Electronics
www.ti.com/consumer-apps
DSP
dsp.ti.com
Energy and Lighting
www.ti.com/energy
Clocks and Timers
www.ti.com/clocks
Industrial
www.ti.com/industrial
Interface
interface.ti.com
Medical
www.ti.com/medical
Logic
logic.ti.com
Security
www.ti.com/security
Power Mgmt
power.ti.com
Space, Avionics and Defense
www.ti.com/space-avionics-defense
Microcontrollers
microcontroller.ti.com
Video and Imaging
www.ti.com/video
RFID
www.ti-rfid.com
OMAP Mobile Processors
www.ti.com/omap
TI E2E Community
e2e.ti.com
Wireless Connectivity
www.ti.com/wirelessconnectivity
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2012, Texas Instruments Incorporated
Similar pages