DS10BR254
1.5 Gbps 1:4 LVDS Repeater
DS10BR254 1.5 Gbps 1:4 LVDS Repeater
December 14, 2007
General Description
The DS10BR254 is a 1.5 Gbps 1:4 LVDS repeater optimized
for high-speed signal routing and distribution over FR-4 printed circuit board backplanes and balanced cables. Fully differential signal paths ensure exceptional signal integrity and
noise immunity.
The device has two different LVDS input channels and a select pin determines which input is active. A loss-of-signal
) circuit monitors both input channels and a unique
(LOS
LOS pin is asserted when no signal is detected at that input.
Wide input common mode range allows the switch to accept
signals with LVDS, CML and LVPECL levels; the output levels
are LVDS. A very small package footprint requires a minimal
space on the board while the flow-through pinout allows easy
board layout. Each differential input and output is internally
terminated with a 100Ω resistor to lower device return losses,
reduce component count and further minimize board space.
Typical Application
Features
DC - 1.5 Gbps low jitter, low skew, low power operation
■
Wide Input Common Mode Voltage Range allows for DC-
■
coupled interface to LVDS, CML and LVPECL drivers
Redundant inputs
■
circuitry detects open inputs fault condition
LOS
■
Integrated 100Ω input and output terminations
■
8 kV ESD on LVDS I/O pins protects adjoining
■
components
Small 6 mm x 6 mm LLP-40 space saving package
■
Applications
Clock distribution
■
Clock and data buffering and muxing
■
OC-12 / STM-4
■
SD/HD SDI Routers
■
30007803
© 2007 National Semiconductor Corporation 300078 www.national.com
Ordering Code
NSID Function
DS10BR254TSQ 1:4 Repeater
DS10BR254
Block Diagram
Connection Diagram
DS10BR254 Pin Diagram
30007801
30007802
www.national.com 2
Pin Descriptions
DS10BR254
Pin Name Pin
Number
IN1+, IN1-,
IN2+, IN2-,
OUT0+, OUT0-,
OUT1+, OUT1-,
OUT2+, OUT2-,
OUT3+, OUT3-
SEL_in 14 I, LVCMOS This pin selects which LVDS input is active.
LOS1,
LOS2
PWDN0,
PWDN1,
PWDN2,
PWDN3
PWDN 38 I, LVCMOS Device power down pin. When the PWDN is set to L, the device
VDD 3, 8,
GND 16, DAP Power Ground pin and a pad (DAP - die attach pad).
NC 1, 2
4, 5,
6, 7,
29, 28,
27, 26,
24, 23,
22, 21
37,
36
35,
34
33,
32
15,25, 30
9, 10,
11, 12,
13, 17,
18, 19,
20, 31,
39, 40
I/O, Type Pin Description
I, LVDS Inverting and non-inverting high speed LVDS input pins.
O, LVDS Inverting and non-inverting high speed LVDS output pins.
O, LVCMOS Loss Of Signal output pins, LOSn report when an open input fault
condition is detected at the input, INn. These are open drain
outputs. External pull up resistors are required.
I, LVCMOS Channel output power down pin. When the PWDNn is set to L, the
channel output OUTn is in the power down mode.
is in the power down mode.
Power Power supply pins.
NC NO CONNECT pins. May be left floating.
3 www.national.com
Absolute Maximum Ratings (Note 4)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
DS10BR254
Supply Voltage −0.3V to +4V
LVCMOS Input Voltage −0.3V to (VCC + 0.3V)
LVCMOS Output Voltage −0.3V to (VCC + 0.3V)
LVDS Input Voltage −0.3V to +4V
LVDS Differential Input Voltage 0.0V to +1V
LVDS Output Voltage −0.3V to (VCC + 0.3V)
LVDS Differential Output Voltage 0.0V to +1V
LVDS Output Short Circuit Current
Duration
Junction Temperature +150°C
Storage Temperature Range −65°C to +150°C
Lead Temperature Range
Soldering (4 sec.) +260°C
Maximum Package Power Dissipation at 25°C
SQA Package 4.65W
Derate SQA Package 37.2 mW/°C above +25°C
5 ms
Package Thermal Resistance
θ
θ
JA
JC
+26.9°C/W
+3.8°C/W
ESD Susceptibility
HBM (Note 1)
MM (Note 2)
CDM (Note 3)
Note 1: Human Body Model, applicable std. JESD22-A114C
Note 2: Machine Model, applicable std. JESD22-A115-A
Note 3: Field Induced Charge Device Model, applicable std.
JESD22-C101-C
Recommended Operating Conditions
Min Typ Max Units
Supply Voltage (VCC) 3.0 3.3 3.6 V
Receiver Differential Input
Voltage (VID)
Operating Free Air
Temperature (TA)
0 1 V
−40 +25 +85 °C
Electrical Characteristics
Over recommended operating supply and temperature ranges unless otherwise specified. (Notes 5, 6, 7)
Symbol Parameter Conditions Min Typ Max Units
LVCMOS DC SPECIFICATIONS
V
IH
V
IL
I
IH
I
IL
V
CL
V
OL
LVDS INPUT DC SPECIFICATIONS
V
ID
V
TH
V
TL
V
CMR
I
IN
C
IN
R
IN
High Level Input Voltage 2.0 V
DD
Low Level Input Voltage GND 0.8 V
High Level Input Current VIN = 3.6V
0 ±10
VCC = 3.6V
Low Level Input Current VIN = GND
0 ±10
VCC = 3.6V
Input Clamp Voltage ICL = −18 mA, VCC = 0V −0.9 −1.5 V
Low Level Output Voltage IOL= 4 mA 0.26 0.4 V
Input Differential Voltage 0 1 V
Differential Input High Threshold
Differential Input Low Threshold
VCM = +0.05V or VCC-0.05V
0 +100 mV
−100 0 mV
Common Mode Voltage Range VID = 100 mV 0.05 VCC -
0.05
Input Current
VIN = +3.6V or 0V
VCC = 3.6V or 0V
Input Capacitance Any LVDS Input Pin to GND
Input Termination Resistor Between IN+ and IN-
±1 ±10
1.7 pF
100
≥8 kV
≥250V
≥1250V
V
μA
μA
V
μA
Ω
www.national.com 4
Symbol Parameter Conditions Min Typ Max Units
LVDS OUTPUT DC SPECIFICATIONS
V
ΔV
V
ΔV
I
OS
C
R
OD
OS
OUT
OUT
Differential Output Voltage
Change in Magnitude of VOD for Complimentary
OD
Output States
Offset Voltage
Change in Magnitude of VOS for Complimentary
OS
Output States
RL = 100Ω
RL = 100Ω
250 350 450 mV
-35 35 mV
1.05 1.2 1.375 V
-35 35 mV
Output Short Circuit Current (Note 8) OUT to GND -35 -55 mA
OUT to V
CC
Output Capacitance Any LVDS Output Pin to GND
Output Termination Resistor Between OUT+ and OUT-
7 55 mA
1.2 pF
100
Ω
SUPPLY CURRENT
I
I
CC
CCZ
Supply Current PWDN = H 113 135 mA
Power Down Supply Current PWDN = L 50 60 mA
Note 4: “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 5: 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 6: Current into device pins is defined as positive. Current out of device pins is defined as negative. All voltages are referenced to ground except VOD and
ΔVOD.
Note 7: Typical values represent most likely parametric norms for VCC = +3.3V and TA = +25°C, and at the Recommended Operation Conditions at the time of
product characterization and are not guaranteed.
Note 8: Output short circuit current (IOS) is specified as magnitude only, minus sign indicates direction only.
DS10BR254
5 www.national.com
AC Electrical Characteristics
Over recommended operating supply and temperature ranges unless otherwise specified.
DS10BR254
Symbol Parameter Conditions Min Typ Max Units
LVDS OUTPUT AC SPECIFICATIONS
t
PLHD
t
PHLD
Differential Propagation Delay Low to
High (Note 11)
Differential Propagation Delay High to
RL = 100Ω
440 650 ps
400 650 ps
Low (Note 11)
t
SKD1
Pulse Skew |t
PLHD
− t
PHLD
|
40 100 ps
(Notes 11, 12)
t
SKD2
Channel to Channel Skew
40 125 ps
(Notes 11, 13)
t
SKD3
Part to Part Skew
50 200 ps
(Notes 11, 14)
t
t
t
t
t
LHT
HLT
ON
OFF
SEL
Rise Time (Note 11)
Fall Time (Note 11) 150 300 ps
Any PWDN to Output Active Time
Any PWDN to Output Inactive Time
Select Time
RL = 100Ω
150 300 ps
8 20
5 12 ns
5 12 ns
JITTER PERFORMANCE (Note 11)
t
RJ1
t
RJ2
t
RJ3
t
RJ4
t
DJ1
t
DJ2
t
DJ3
t
DJ4
t
TJ1
t
TJ2
t
TJ3
t
TJ4
Note 9: 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 10: Typical values represent most likely parametric norms for VCC = +3.3V and TA = +25°C, and at the Recommended Operation Conditions at the time of
product characterization and are not guaranteed.
Note 11: Specification is guaranteed by characterization and is not tested in production.
Note 12: t
going edge of the same channel.
Note 13: t
all outputs).
Note 14: t
devices at the same VCC and within 5°C of each other within the operating temperature range.
Note 15: Measured on a clock edge with a histogram and an acummulation of 1500 histogram hits. Input stimulus jitter is subtracted geometrically.
Note 16: Tested with a combination of the 1100000101 (K28.5+ character) and 0011111010 (K28.5- character) patterns. Input stimulus jitter is subtracted
algebraically.
Note 17: Measured on an eye diagram with a histogram and an acummulation of 3500 histogram hits. Input stimulus jitter is subtracted.
Random Jitter
(RMS Value)
(Note 15)
Deterministic Jitter
(Peak to Peak Value)
(Note 16)
Total Jitter
(Note 17)
, |t
− t
SKD1
PLHD
, Channel to Channel Skew, is the difference in propagation delay (t
SKD2
, Part to Part Skew, is defined as the difference between the minimum and maximum differential propagation delays. This specification applies to
SKD3
|, Pulse Skew, is the magnitude difference in differential propagation delay time between the positive going edge and the negative
PHLD
VID = 350 mV
VCM = 1.2V
Clock (RZ)
VID = 350 mV
VCM = 1.2V
K28.5 (NRZ)
VID = 350 mV
VCM = 1.2V
PRBS-23 (NRZ)
or t
PLHD
135 MHz 0.5 1 ps
311 MHz 0.5 1 ps
503 MHz 0.5 1 ps
750 MHz 0.5 1 ps
270 Mbps 6 22 ps
622 Mbps 6 21 ps
1.0625 Gbps 9 18 ps
1.5 Gbps 9 17 ps
270 Mbps 0.01 0.03
622 Mbps 0.01 0.03
1.0625 Gbps 0.01 0.04
1.5 Gbps 0.01 0.06
) among all output channels in Broadcast mode (any one input to
PHLD
UI
UI
UI
UI
μs
P-P
P-P
P-P
P-P
www.national.com 6
DC Test Circuits
FIGURE 1. Differential Driver DC Test Circuit
AC Test Circuits and Timing Diagrams
DS10BR254
30007820
FIGURE 2. Differential Driver AC Test Circuit
30007822
FIGURE 3. Propagation Delay Timing Diagram
FIGURE 4. LVDS Output Transition Times
30007821
30007823
7 www.national.com
Functional Description
The DS10BR254 is a 1.5 Gbps 1:4 LVDS repeater optimized
for high-speed signal routing and distribution over lossy FR-4
printed circuit board backplanes and balanced cables.
DS10BR254
TABLE 1. Input Select Truth Table
CONTROL Pin (SEL_in) State Input Selected
0 IN1
1 IN2
www.national.com 8
DS10BR254
Input Interfacing
The DS10BR254 accepts differential signals and allows simple AC or DC coupling. With a wide common mode range, the
DS10BR254 can be DC-coupled with all common differential
Typical LVDS Driver DC-Coupled Interface to an DS10BR254 Input
drivers (i.e. LVPECL, LVDS, CML). The following three figures illustrate typical DC-coupled interface to common differential drivers. Note that the DS10BR254 inputs are internally
terminated with a 100Ω resistor.
30007831
Typical CML Driver DC-Coupled Interface to an DS10BR254 Input
Typical LVPECL Driver DC-Coupled Interface to an DS10BR254 Input
30007832
30007833
9 www.national.com
Output Interfacing
The DS10BR254 outputs signals compliant to the LVDS standard. Its outputs can be DC-coupled to most common differential receivers. The following figure illustrates typical DC-
DS10BR254
coupled interface to common differential receivers and
assumes that the receivers have high impedance inputs.
While most differential receivers have a common mode input
range that can accomodate LVDS compliant signals, it is recommended to check respective receiver's data sheet prior to
implementing the suggested interface implementation.
Typical DS10BR254 Output DC-Coupled Interface to an LVDS, CML or LVPECL Receiver
30007834
www.national.com 10
Typical Performance
DS10BR254
A 1.5 Gbps NRZ PRBS-7 After 2"
Differential FR-4 Stripline
V:100 mV / DIV, H:100 ps / DIV
A 622 Mbps NRZ PRBS-7 After 2"
Differential FR-4 Stripline
V:100 mV / DIV, H:200 ps / DIV
30007863
30007861
A 1.06 Gbps NRZ PRBS-7 After 2"
Differential FR-4 Stripline
V:100 mV / DIV, H:200 ps / DIV
A 270 Mbps NRZ PRBS-7 After 2"
Differential FR-4 Stripline
V:100 mV / DIV, H:500 ps / DIV
30007862
30007860
Supply Current as a Function of a Number of Outputs Used
30007870
11 www.national.com
Physical Dimensions inches (millimeters) unless otherwise noted
DS10BR254
Order Number DS10BR254TSQ
(See AN-1187 for PCB Design and Assembly Recommendations)
NS Package Number SQA40A
www.national.com 12
Notes
DS10BR254
13 www.national.com
Notes
For more National Semiconductor product information and proven design tools, visit the following Web sites at:
Products Design Support
Amplifiers www.national.com/amplifiers WEBENCH www.national.com/webench
Audio www.national.com/audio Analog University www.national.com/AU
Clock Conditioners www.national.com/timing App Notes www.national.com/appnotes
Data Converters www.national.com/adc Distributors www.national.com/contacts
Displays www.national.com/displays Green Compliance www.national.com/quality/green
Ethernet www.national.com/ethernet Packaging www.national.com/packaging
Interface www.national.com/interface Quality and Reliability www.national.com/quality
LVDS www.national.com/lvds Reference Designs www.national.com/refdesigns
Power Management www.national.com/power Feedback www.national.com/feedback
Switching Regulators www.national.com/switchers
LDOs www.national.com/ldo
LED Lighting www.national.com/led
PowerWise www.national.com/powerwise
Serial Digital Interface (SDI) www.national.com/sdi
DS10BR254 1.5 Gbps 1:4 LVDS Repeater
Temperature Sensors www.national.com/tempsensors
Wireless (PLL/VCO) www.national.com/wireless
THE CONTENTS OF THIS DOCUMENT ARE PROVIDED IN CONNECTION WITH NATIONAL SEMICONDUCTOR CORPORATION
(“NATIONAL”) PRODUCTS. NATIONAL MAKES NO REPRESENTATIONS OR WARRANTIES WITH RESPECT TO THE ACCURACY
OR COMPLETENESS OF THE CONTENTS OF THIS PUBLICATION AND RESERVES THE RIGHT TO MAKE CHANGES TO
SPECIFICATIONS AND PRODUCT DESCRIPTIONS AT ANY TIME WITHOUT NOTICE. NO LICENSE, WHETHER EXPRESS,
IMPLIED, ARISING BY ESTOPPEL OR OTHERWISE, TO ANY INTELLECTUAL PROPERTY RIGHTS IS GRANTED BY THIS
DOCUMENT.
TESTING AND OTHER QUALITY CONTROLS ARE USED TO THE EXTENT NATIONAL DEEMS NECESSARY TO SUPPORT
NATIONAL’S PRODUCT WARRANTY. EXCEPT WHERE MANDATED BY GOVERNMENT REQUIREMENTS, TESTING OF ALL
PARAMETERS OF EACH PRODUCT IS NOT NECESSARILY PERFORMED. NATIONAL ASSUMES NO LIABILITY FOR
APPLICATIONS ASSISTANCE OR BUYER PRODUCT DESIGN. BUYERS ARE RESPONSIBLE FOR THEIR PRODUCTS AND
APPLICATIONS USING NATIONAL COMPONENTS. PRIOR TO USING OR DISTRIBUTING ANY PRODUCTS THAT INCLUDE
NATIONAL COMPONENTS, BUYERS SHOULD PROVIDE ADEQUATE DESIGN, TESTING AND OPERATING SAFEGUARDS.
EXCEPT AS PROVIDED IN NATIONAL’S TERMS AND CONDITIONS OF SALE FOR SUCH PRODUCTS, NATIONAL ASSUMES NO
LIABILITY WHATSOEVER, AND NATIONAL DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY RELATING TO THE SALE
AND/OR USE OF NATIONAL PRODUCTS INCLUDING LIABILITY OR WARRANTIES RELATING TO FITNESS FOR A PARTICULAR
PURPOSE, MERCHANTABILITY, OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY
RIGHT.
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR
SYSTEMS WITHOUT THE EXPRESS PRIOR WRITTEN APPROVAL OF THE CHIEF EXECUTIVE OFFICER AND GENERAL
COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:
Life support devices or systems are devices which (a) are intended for surgical implant into the body, or (b) support or sustain life and
whose failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably expected
to result in a significant injury to the user. A critical component is any component in a life support device or system whose failure to perform
can be reasonably expected to cause the failure of the life support device or system or to affect its safety or effectiveness.
National Semiconductor and the National Semiconductor logo are registered trademarks of National Semiconductor Corporation. All other
brand or product names may be trademarks or registered trademarks of their respective holders.
Copyright© 2007 National Semiconductor Corporation
For the most current product information visit us at www.national.com
www.national.com
National Semiconductor
Americas Customer
Support Center
Email:
new.feedback@nsc.com
Tel: 1-800-272-9959
National Semiconductor Europe
Customer Support Center
Fax: +49 (0) 180-530-85-86
Email: europe.support@nsc.com
Deutsch Tel: +49 (0) 69 9508 6208
English Tel: +49 (0) 870 24 0 2171
Français Tel: +33 (0) 1 41 91 8790
National Semiconductor Asia
Pacific Customer Support Center
Email: ap.support@nsc.com
National Semiconductor Japan
Customer Support Center
Fax: 81-3-5639-7507
Email: jpn.feedback@nsc.com
Tel: 81-3-5639-7560
Loading...