NSC DS25BR110TSD 3.125 gbps lvds buffer with transmit pre-emphasis Datasheet

DS25BR120
3.125 Gbps LVDS Buffer with Transmit Pre-Emphasis
General Description
Features
The DS25BR120 is a single channel 3.125 Gbps LVDS buffer
optimized for high-speed signal transmission over lossy FR-4
printed circuit board backplanes and balanced metallic cables. Fully differential signal paths ensure exceptional signal
integrity and noise immunity.
The DS25BR120 features four levels of pre-emphasis (PE)
for use as an optimized driver device. Other LVDS devices
with similar IO characteristics include the following products.
The DS25BR110 features four levels of equalization for use
as an optimized receiver device, while the DS25BR100 features both pre-emphasis and equalization for use as an optimized repeater device. The DS25BR150 is a buffer/repeater
with the lowest power consumption and does not feature
transmit pre-emphasis nor receive equalization.
Wide input common mode range allows the receiver to accept
signals with LVDS, CML and LVPECL levels; the output levels
are LVDS. A very small package footprint requires minimal
space on the board while the flow-through pinout allows easy
board layout. The differential inputs and outputs are internally
terminated with a 100Ω resistor to lower device input and output return losses, reduce component count and further minimize board space.
■ DC - 3.125 Gbps low jitter, high noise immunity, low power
operation
■ Four levels of transmit pre-emphasis drive lossy
backplanes and cables
■ On-chip 100Ω input and output termination minimizes
insertion and return losses, reduces component count and
minimizes board space
■ 7 kV ESD on LVDS I/O pins protects adjoining
components
■ Small 3 mm x 3 mm 8-LLP space saving package
Applications
■ Clock and data buffering
■ Metallic cable driving
■ FR-4 driving
Typical Application
30005410
© 2007 National Semiconductor Corporation
300054
www.national.com
DS25BR120 3.125 Gbps LVDS Buffer with Transmit Pre-Emphasis
November 6, 2007
DS25BR120
Block Diagram
30005402
Pin Diagram
30005405
Pin Descriptions
Pin Name
Pin Name
Pin Type
Pin Description
PE1
1
Input
Pre-emphasis select pin.
IN+
2
Input
Non-inverting LVDS input pin.
IN-
3
Input
Inverting LVDS input pin.
PE0
4
Input
Pre-emphasis select pin.
NC
5
NA
"NO CONNECT" pin.
OUT-
6
Output
Inverting LVDS output pin.
OUT+
7
Output
Non-inverting LVDS Output pin.
VCC
8
Power
Power supply pin.
GND
DAP
Power
Ground pad (DAP - die attach pad)
Pre-Emphasis Truth Table
PE1
PE0
Pre-emphasis Level
0
0
Off
0
1
Low (Approx. 3 dB at 1.56 GHz)
1
0
Medium (Approx. 6 dB at 1.56 GHz)
1
1
High (Approx. 9 dB at 1.56 GHz)
Ordering Codes and Configurations
NSID
Function
DS25BR100TSD
Buffer/Repeater
DS25BR110TSD
Receiver
Off / Low / Medium / High
NA
DS25BR120TSD
Driver
NA
Off / Low / Medium / High
DS25BR150TSD
Buffer/Repeater
NA
NA
www.national.com
2
Available Equalization
Levels
Available Pre-emphasis
Levels
Low / Medium
Off / Medium
θJA
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
+60.0°C/W
θJC
ESD Susceptibility
HBM (Note 1)
Supply Voltage (VCC)
−0.3V to +4V
LVCMOS Input Voltage (PE0, PE1)
−0.3V to (VCC + 0.3V)
LVDS Input Voltage (IN+, IN−)
−0.3V to +4V
LVDS Differential Input Voltage ((IN+) - (IN−))
0V to 1.0V
LVDS Output Voltage (OUT+, OUT−)
−0.3V to (VCC + 0.3V)
LVDS Differential Output Voltage ((OUT+) - (OUT−)) 0V to 1.0V
LVDS Output Short Circuit Current
5 ms
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
SDA Package
2.08W
Derate SDA Package
16.7 mW/°C above +25°C
+12.3°C/W
≥7 kV
≥250V
≥1250V
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
Supply Voltage (VCC)
Receiver Differential Input
Voltage (VID)
Operating Free Air
Temperature (TA)
Min
3.0
0
Typ
3.3
Max
3.6
1.0
Units
V
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 INPUT DC SPECIFICATIONS (PE0, PE1)
VIH
High Level Input Voltage
2.0
VCC
V
VIL
Low Level Input Voltage
GND
0.8
V
IIH
High Level Input Current
VIN = 3.6V
VCC = 3.6V
0
±10
μA
IIL
Low Level Input Current
VIN = GND
VCC = 3.6V
0
±10
μA
VCL
Input Clamp Voltage
ICL = −18 mA, VCC = 0V
-0.9
−1.5
V
350
450
mV
35
mV
1.375
V
35
mV
LVDS OUTPUT DC SPECIFICATIONS (OUT+, OUT-)
VOD
Differential Output Voltage
250
ΔVOD
Change in Magnitude of VOD for Complimentary
Output States
VOS
Offset Voltage
ΔVOS
Change in Magnitude of VOS for Complimentary
Output States
RL = 100Ω
IOS
Output Short Circuit Current (Note 8)
OUT to GND
PE0 = PE1 = 0
-35
-55
mA
OUT to VCC
PE0 = PE1 = 0
7
55
mA
RL = 100Ω
-35
1.05
1.2
-35
COUT
Output Capacitance
Any LVDS Output Pin to GND
1.2
pF
ROUT
Output Termination Resistor
Between OUT+ and OUT-
100
Ω
3
www.national.com
DS25BR120
Package Thermal Resistance
Absolute Maximum Ratings (Note 4)
DS25BR120
Symbol
Parameter
Conditions
Min
Typ
Max
Units
1
V
0
+100
mV
LVDS INPUT DC SPECIFICATIONS (IN+, IN-)
VID
Input Differential Voltage
VTH
Differential Input High Threshold
0
VTL
Differential Input Low Threshold
VCMR
Common Mode Voltage Range
VID = 100 mV
IIN
Input Current
VIN = 3.6V or 0V
VCC = 3.6V or 0V
±1
CIN
Input Capacitance
Any LVDS Input Pin to GND
1.7
pF
RIN
Input Termination Resistor
Between IN+ and IN-
100
Ω
PE0 = 0, PE1 = 0
35
VCM = +0.05V or VCC-0.05V
−100
0
0.05
mV
VCC 0.05
V
±10
μA
SUPPLY CURRENT
ICC
Supply Current
43
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.
www.national.com
4
(Note 11)
Over recommended operating supply and temperature ranges unless otherwise specified. (Notes 9, 10)
Symbol
Parameter
Conditions
Min
Typ
Max
Units
350
465
ps
350
465
ps
LVDS OUTPUT AC SPECIFICATIONS (OUT+, OUT-)
tPHLD
Differential Propagation Delay High to Low
tPLHD
Differential Propagation Delay Low to High
tSKD1
Pulse Skew |tPLHD − tPHLD| (Note 12)
45
100
ps
tSKD2
Part to Part Skew (Note 13)
45
150
ps
tLHT
Rise Time
80
150
ps
tHLT
Fall Time
80
150
ps
RL = 100Ω
RL = 100Ω
JITTER PERFORMANCE WITH PE = OFF
tRJ1A
tRJ2A
tDJ1A
tDJ2A
tTJ1A
tTJ2A
Random Jitter (RMS Value)
No Test Channels
(Note 14)
VID = 350 mV
VCM = 1.2V
Clock (RZ)
PE0 = 0, PE1 = 0
2.5 Gbps
0.5
1
ps
3.125 Gbps
0.5
1
ps
Deterministic Jitter (Peak to Peak)
No Test Channels
(Note 15)
VID = 350 mV
VCM = 1.2V
K28.5 (NRZ)
PE0 = 0, PE1 = 0
2.5 Gbps
9
31
ps
3.125 Gbps
16
40
ps
Total Jitter (Peak to Peak)
No Test Channels
(Note 16)
VID = 350 mV
VCM = 1.2V
PRBS-23 (NRZ)
PE0 = 0, PE1 = 0
2.5 Gbps
0.05
0.13
UIP-P
3.125 Gbps
0.09
0.16
UIP-P
5
www.national.com
DS25BR120
AC Electrical Characteristics
DS25BR120
Symbol
Parameter
Conditions
Min
Typ
Max
Units
JITTER PERFORMANCE WITH PE = LOW (Figures 5 and 6)
tRJ1B
tRJ2B
tDJ1B
tDJ2B
tTJ1B
tTJ2B
Random Jitter (RMS Value)
Test Channel A
(Note 14)
VID = 350 mV
VCM = 1.2V
Clock (RZ)
PE0 = 1, PE1 = 0
2.5 Gbps
0.5
1.3
ps
3.125 Gbps
0.5
1.3
ps
Deterministic Jitter (Peak to Peak)
Test Channel A
(Note 15)
VID = 350 mV
VCM = 1.2V
K28.5 (NRZ)
PE0 = 1, PE1 = 0
2.5 Gbps
17
31
ps
3.125 Gbps
18
40
ps
Total Jitter (Peak to Peak)
Test Channel A
(Note 16)
VID = 350 mV
VCM = 1.2V
PRBS-23 (NRZ)
PE0 = 1, PE1 = 0
2.5 Gbps
0.09
0.14
UIP-P
3.125 Gbps
0.12
0.19
UIP-P
JITTER PERFORMANCE WITH PE = MEDIUM (Figures 5 and 6)
tRJ1C
tRJ2C
tDJ1C
tDJ2C
tTJ1C
tTJ2C
Random Jitter (RMS Value)
Test Channel B
(Note 14)
VID = 350 mV
VCM = 1.2V
Clock (RZ)
PE0 = 0, PE1 = 1
2.5 Gbps
0.5
1.2
ps
3.125 Gbps
0.5
1.2
ps
Deterministic Jitter (Peak to Peak)
Test Channel B
(Note 15)
VID = 350 mV
VCM = 1.2V
K28.5 (NRZ)
PE0 = 0, PE1 = 1
2.5 Gbps
21
44
ps
3.125 Gbps
27
48
ps
Total Jitter (Peak to Peak)
Test Channel B
(Note 16)
VID = 350 mV
VCM = 1.2V
PRBS-23 (NRZ)
PE0 = 0, PE1 = 1
2.5 Gbps
0.09
0.16
UIP-P
3.125 Gbps
0.13
0.23
UIP-P
JITTER PERFORMANCE WITH PE = HIGH (Figures 5 and 6)
tRJ1D
tRJ2D
tDJ1D
tDJ2D
tTJ1D
tTJ2D
Random Jitter (RMS Value)
Test Channel C
(Note 14)
VID = 350 mV
VCM = 1.2V
Clock (RZ)
PE0 = 1, PE1 = 1
2.5 Gbps
0.5
1.2
ps
3.125 Gbps
0.5
1.2
ps
Deterministic Jitter (Peak to Peak)
Test Channel C
(Note 15)
VID = 350 mV
VCM = 1.2V
K28.5 (NRZ)
PE0 = 1, PE1 = 1
2.5 Gbps
30
65
ps
3.125 Gbps
30
58
ps
Total Jitter (Peak to Peak)
Test Channel C
(Note 16)
VID = 350 mV
VCM = 1.2V
PRBS-23 (NRZ)
PE0 = 1, PE1 = 1
2.5 Gbps
0.09
0.20
UIP-P
3.125 Gbps
0.13
0.22
UIP-P
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: tSKD1, |tPLHD − tPHLD|, is the magnitude difference in differential propagation delay time between the positive going edge and the negative going edge of
the same channel.
Note 13: tSKD2, Part to Part Skew, is defined as the difference between the minimum and maximum specified differential propagation delays. This specification
applies to devices at the same VCC and within 5°C of each other within the operating temperature range.
Note 14: Measured on a clock edge with a histogram and an acummulation of 1500 histogram hits. Input stimulus jitter is subtracted geometrically.
Note 15: Tested with a combination of the 1100000101 (K28.5+ character) and 0011111010 (K28.5- character) patterns. Input stimulus jitter is subtracted
algebraically.
Note 16: Measured on an eye diagram with a histogram and an acummulation of 3500 histogram hits. Input stimulus jitter is subtracted.
www.national.com
6
DS25BR120
DC Test Circuits
30005420
FIGURE 1. Differential Driver DC Test Circuit
AC Test Circuits and Timing Diagrams
30005421
FIGURE 2. Differential Driver AC Test Circuit
30005422
FIGURE 3. Propagation Delay Timing Diagram
30005423
FIGURE 4. LVDS Output Transition Times
7
www.national.com
DS25BR120
Pre-Emphasis Test Circuits
30005427
FIGURE 5. Pre-emphasis Performance Test Circuit
30005428
FIGURE 6. Test Channel Description
Test Channel Loss Characteristics
The test channel was fabricated with Polyclad PCL-FR-370-Laminate/PCL-FRP-370 Prepreg materials (Dielectric constant of 3.7
and Loss Tangent of 0.02). The edge coupled differential striplines have the following geometries: Trace Width (W) = 5 mils, Gap
(S) = 5 mils, Height (B) = 16 mils.
Test Channel
Length
(inches)
500 MHz
750 MHz
1000 MHz
Insertion Loss (dB)
1250 MHz
1500 MHz
1560 MHz
A
10
-1.2
-1.7
-2.0
-2.4
-2.7
-2.8
B
20
-2.6
-3.5
-4.1
-4.8
-5.5
-5.6
C
30
-4.3
-5.7
-7.0
-8.2
-9.4
-9.7
D
15
-1.6
-2.2
-2.7
-3.2
-3.7
-3.8
E
30
-3.4
-4.5
-5.6
-6.6
-7.7
-7.9
F
60
-7.8
-10.3
-12.4
-14.5
-16.6
-17.0
www.national.com
8
INPUT INTERFACING
The DS25BR120 accepts differential signals and allows simple AC or DC coupling. With a wide common mode range, the
DS25BR120 can be DC-coupled with all common differential drivers (i.e. LVPECL, LVDS, CML). The following three figures illustrate typical DC-coupled interface to common differential drivers. Note that the DS25BR120 inputs are internally terminated with
a 100Ω resistor.
30005411
Typical LVDS Driver DC-Coupled Interface to DS25BR120 Input
30005412
Typical CML Driver DC-Coupled Interface to DS25BR120 Input
30005413
Typical LVPECL Driver DC-Coupled Interface to DS25BR120 Input
9
www.national.com
DS25BR120
Device Operation
DS25BR120
OUTPUT INTERFACING
The DS25BR120 outputs signals compliant to the LVDS standard. It can be DC-coupled to most common differential receivers.
The following figure illustrates typical DC-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.
30005414
Typical DS25BR120 Output DC-Coupled Interface to an LVDS, CML or LVPECL Receiver
www.national.com
10
DS25BR120
Typical Performance
30005435
30005434
Maximum Data Rate as a Function of CAT7
(Siemon Tera) Length
Maximum Data Rate as a Function of CAT5e
(Belden 1700A) Length
30005437
30005436
Maximum Data Rate as a Function of CAT5e
(Belden 1700A) Length
DS25BR120 Used as a Driver
DS25BR110 Used as a Receiver
Maximum Data Rate as a Function of CAT5e
(Belden 1700A) Length
DS25BR120 Used as a Driver
DS25BR110 Used as a Receiver
30005438
Power Supply Current as a Function of Frequency
11
www.national.com
DS25BR120
30005430
30005431
A 2.5 Gbps NRZ PRBS-7 After 40"
Differential FR-4 Stripline
V:125 mV / DIV, H:75 ps / DIV
An Equalized (with PE) 2.5 Gbps NRZ PRBS-7 After 40"
Differential FR-4 Stripline
V:125 mV / DIV, H:75 ps / DIV
30005432
30005433
A 3.125 Gbps NRZ PRBS-7 After 40"
Differential FR-4 Stripline
V:125 mV / DIV, H:50 ps / DIV
www.national.com
An Equalized (with PE) 3.125 Gbps NRZ PRBS-7 After 40"
Differential FR-4 Stripline
V:125 mV / DIV, H:50 ps / DIV
12
DS25BR120
Physical Dimensions inches (millimeters) unless otherwise noted
Order Number DS25BR120TSD
NS Package Number SDA08A
(See AN-1187 for PCB Design and Assembly Recommendations)
13
www.national.com
DS25BR120 3.125 Gbps LVDS Buffer with Transmit Pre-Emphasis
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
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
National Semiconductor
Americas Customer
Support Center
Email:
[email protected]
Tel: 1-800-272-9959
www.national.com
National Semiconductor Europe
Customer Support Center
Fax: +49 (0) 180-530-85-86
Email: [email protected]
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: [email protected]
National Semiconductor Japan
Customer Support Center
Fax: 81-3-5639-7507
Email: [email protected]
Tel: 81-3-5639-7560
Similar pages