AMSCO AS1154

D a ta S he e t
A S 11 5 6 / A S 11 5 4
S i n g l e / D u a l LV D S D r i v e r
1 General Description
2 Key Features
The AS1156/AS1154 is a Single/Dual Flow-Through
LVDS (Low-Voltage Differential Signaling) Line Driver
which accepts and converts LVTTL/LVCMOS input levels into LVDS output signals. The device is perfect for
low-power low-noise applications requiring high signaling rates and reduced EMI emissions.
The device is guaranteed to transmit data at speeds up
to 800Mbps (400MHz) over controlled impedance media
of approximately 100Ω. Supported transmission media
are PCB traces, backplanes, and cables.
The AS1156 is a single LVDS transmitter, and the
AS1154 is a dual LVDS transmitter.
Outputs conform to the ANSI TIA/EIA-644 LVDS standards. Flow-through pinout simplifies PC board layout
and reduces crosstalk by separating the LVTTL/LVCMOS inputs and LVDS outputs.
The AS1156/AS1154 operates from a single +3.3V supply and is specified for operation from -40 to +85°C.
„
Flow-Through Pinout
„
Guaranteed 800Mbps Data Rate
„
250ps Pulse Skew (Max)
„
Conforms to ANSI TIA/EIA-644 LVDS Standards
„
Single +3.3V Supply
„
Operating Temperature Range: -40 to +85°C
„
8-Pin SOIC Package
3 Applications
Digital Copiers, Laser Printers, Cellular Phone Base Stations, Add/Drop Muxes, Digital Cross-Connects,
DSLAMs, Network Switches/Routers, Backplane Interconnect, Clock Distribution Computers, Intelligent Instruments, Controllers, Critical Microprocessors and
Microcontrollers, Power Monitoring, and Portable/Battery-Powered Equipment.
Figure 1. Block Diagram
AS1156
VCC
AS1154
VCC
OUT1-
IN1
N/C
OUT1Tx
Tx
OUT1+
OUT1+
IN1
N/C
IN2
OUT2+
Tx
GND
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N/C
GND
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OUT2-
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AS1156/AS1154
Data Sheet - P i n o u t
4 Pinout
Pin Assignments
Figure 2. AS1156/AS1154 Pin Assignments (Top View)
VCC
1
8
OUT1-
VCC
1
IN1
2
7
OUT1+
IN1
2
8
OUT1-
7
OUT1+
AS1154
AS1156
N/C
3
6
N/C
IN2
3
6
OUT2+
GND
4
5
N/C
GND
4
5
OUT2-
Pin Descriptions
Table 1. AS1156/AS1154 Pin Descriptions
Pin Number
Pin Name
Description
1
VCC
Power Supply Input. Bypass VCC to GND with 0.1µF and 0.001µF
ceramic capacitors.
2
IN1
LVTTL/LVCMOS Driver Input
IN2
LVTTL/LVCMOS Driver Input
AS1154
AS1156
1
2
3
4
4
GND
Ground
5
OUT2-
Inverting LVDS Driver Output
6
OUT2+
Noninverting LVDS Driver Output
7
OUT1+
Noninverting LVDS Driver Output
8
OUT1-
Inverting LVDS Driver Output
3, 5, 6
N/C
7
8
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Not connected
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AS1156/AS1154
Data Sheet - A b s o l u t e M a x i m u m R a t i n g s
5 Absolute Maximum Ratings
Stresses beyond those listed in Table 2 may cause permanent damage to the device. These are stress ratings only,
and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may
affect device reliability.
Table 2. Absolute Maximum Ratings
Parameter
Limits
Units
VCC to GND
-0.3 to +5.0
V
INx, EN, ENn to GND
-0.3 to (VCC + 0.3)
V
OUTx+, OUTx- to GND
-0.3 to +5
V
Short Circuit Duration (OUTx+, OUTx-)
Continuous
Continuous Power Dissipation
(TA = +70°C)
755
mW
Storage Temperature Range
-65 to +150
ºC
Maximum Junction Temperature
+150
ºC
Operating Temperature Range
-40 to +85
ºC
Notes
Derate 9.4mW/°C Above +70°C
Package Body Temperature
260
ºC
The reflow peak soldering temperature
(body temperature) specified is in
compliance with IPC/JEDEC J-STD020C “Moisture/ Reflow Sensitivity
Classification for Non-Hermetic Solid
State Surface Mount Devices”.
ESD Protection
±4
kV
Human Body Model, INx, OUTx+,
OUTx--
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AS1156/AS1154
Data Sheet - E l e c t r i c a l C h a r a c t e r i s t i c s
6 Electrical Characteristics
DC Electrical Characteristics
(VCC = +3.0 to +3.6V, TA = -40 to +85°C , RL = 100Ω ±1%
Typical values are at VCC = +3.3V, TA = +25°C, Unless Otherwise Noted.) 1
Table 3. DC Electrical Characteristics
Parameter
Symbol
Conditions
Min
Typ
Max
Unit
Differential Output Voltage
VOD
Figure 21 on page 11
250
355
450
mV
Change in Magnitude of VOD
Between Complementary Output
States
ΔVOD
Figure 21 on page 11
1
35
mV
Offset Voltage
VOS
Figure 21 on page 11
1.25
1.375
V
Change in Magnitude of VOS
Between Complementary Output
States
ΔVOS
Figure 21 on page 11
4
25
mV
Output High Voltage
VOH
1.6
V
Output Low Voltage
VOL
Differential Output Short-Circuit
Current 2
IOSD
VOD = 0V
Output Short-Circuit Current
IOS
OUTx+ = 0V at INx = VCC or
OUTx- = 0V at INx = 0V
Power-Off Output Current
IOFF
VCC = 0V or open, OUTx+ = 0V or 3.6V
OUTx- = 0V or 3.6V, RL = ∞
LVDS Output (OUtx+, OUTx-)
1.125
0.90
V
-9
mA
-9
mA
-20
20
µA
-3.7
Inputs (INx)
High-Level Input Voltage
VIH
2.0
VCC
V
Low-Level Input Voltage
VIL
GND
0.8
V
Input Current
IIN
INx = 0V or VCC
-20
20
µA
ICC
RL = ∞ , INx = VCC or 0V for all
channels
2
3.5
mA
RL = 100Ω, INx = VCC or 0V for all
channels, AS1156
5.5
7.5
mA
RL = 100Ω, INx = VCC or 0V for all
channels, AS1154
8.5
12
mA
Supply Current
No-Load Supply Current
Loaded Supply Current
ICCL
Notes:
1. Currents into the device are positive, and current out of the device is negative. All voltages are referenced to
ground except VOD.
2. Guaranteed by correlation data.
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AS1156/AS1154
Data Sheet - E l e c t r i c a l C h a r a c t e r i s t i c s
Switching Characteristics
(VCC = +3.0 to +3.6V, RL = 100Ω ±1%, CL = 2.5pF (differential), TA = -40 to +85°C
Typical values are at VCC = +3.3V, TA = +25ºC, Unless Otherwise Noted.) 1, 2, 3, 10
Table 4. Switching Characteristics
Parameter
Symbol
Conditions
Min
Typ
Max
Unit
Differential Propagation Delay,
High-to-Low
tPHLD
Figure 20 on page 11 and
Figure 21 on page 11
1.1
1.268
1.5
ns
Differential Propagation Delay,
Low-to-High
tPLHD
Figure 20 on page 11 and
Figure 21 on page 11
1.1
1.267
1.5
ns
Differential Pulse Skew 4
tSKD1
Figure 20 on page 11 and
Figure 21 on page 11
90
200
ps
Differential Channel-to-Channel Skew 5
tSKD2
Figure 20 on page 11 and
Figure 21 on page 11
110
250
ps
Differential Part-to-Part Skew 6
tSKD3
Figure 20 on page 11 and
Figure 21 on page 11
750
ps
Differential Part-to-Part Skew 7
tSKD4
Figure 20 on page 11 and
Figure 21 on page 11
900
ps
Rise Time
tTLH
Figure 20 on page 11 and
Figure 21 on page 11
200
356
800
ps
Fall Time
tTHL
Figure 20 on page 11 and
Figure 21 on page 11
200
352
800
ps
Maximum Operating Frequency 8, 9
fMAX
400
MHz
Notes:
1. Parameters are guaranteed by design and characterization.
2. CL includes probe and jig capacitance.
3. Signal generator conditions for dynamic tests: VOL = 0, VOH = 2.4V, f = 100MHz, 50% duty cycle, RO = 50Ω,
tR ≤ 1ns, tF ≤ 1ns (0 to 100%).
4. tSKD1 is the magnitude difference of differential propagation delay. tSKD1 = |tPHLD - tPLHD|.
5. tSKD2 is the magnitude difference of tPHLD or tPLHD of one channel to the tPHLD or tPLHD of another channel on
the same device.
6. tSKD3 is the magnitude difference of any differential propagation delays between devices at the same VCC and
within 5°C of each other.
7. tSKD4 is the magnitude difference of any differential propagation delays between devices operating over the
rated supply and temperature ranges.
8. fMAX signal generator conditions: VOL = 0, VOH = 2.4V, 50% duty cycle, RO = 50Ω,
tR ≤ 1ns, tF ≤ 1ns (0 to 100%).
9. Transmitter output criteria: duty cycle = 45 to 55%, VOD ≥ 250mV.
10. For optimum performance matched circuits should be used.
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AS1156/AS1154
Data Sheet - Ty p i c a l O p e r a t i n g C h a r a c t e r i s t i c s
7 Typical Operating Characteristics
VCC = +3.3V, CLOAD = 2.5pF (differential), Freq = 20MHz, Tamb = +25ºC, unless otherwise noted
Figure 4. Transition Time vs. Temperature
Figure 3. Transition Time vs. VCC
270
350
.
300
tTHL
260
Transition Time (ps)
Transition Time (ps)
.
tTHL
250
240
tTLH
250
150
100
50
230
3
3.1
3.2
tTLH
200
3.3
3.4
3.5
0
-50
3.6
-30
Supply Voltage(V)
-10
10
30
50
70
90
Ambient Temperature(°C)
Figure 5. Differential Pulse Skew vs. VCC
Figure 6. Pulse Skew vs. Temperature
35
70
30
.
60
Pulse Skew (ps)
Differential Pulse Skew (ps)
.
80
50
40
30
20
25
20
15
10
5
10
0
3
3.1
3.2
3.3
3.4
3.5
0
-50
3.6
Supply Voltage(V)
-30
-10
10
30
50
70
90
Ambient Temperature(°C)
Figure 7. Differential Propagation Delay vs. VCC;
Figure 8. Differential Propagation Delay vs. Temp.
1.14
.
.
1.05
Diff. Propagation Delay (ns)
Diff. Propagation Delay (ns)
1.12
1.03
tPHLD
1.01
0.99
0.97
tPLHD
0.95
3
3.1
3.2
3.3
3.4
3.5
3.6
1.1
1.08
tPLHD
1.04
1.02
1
0.98
-50
Supply Voltage(V)
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tPHLD
1.06
-30
-10
10
30
50
70
90
Ambient Temperature(°C)
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AS1156/AS1154
Data Sheet - Ty p i c a l O p e r a t i n g C h a r a c t e r i s t i c s
Figure 10. Differential Output Voltage vs. Frequency
.
350
Differential Output Voltage (mV)
Differential Output Voltage (mV)
.
Figure 9. Differential Output Voltage vs. VCC
345
340
335
330
325
3
3.1
3.2
3.3
3.4
3.5
350
300
250
200
150
100
50
0
3.6
0
50 100 150 200 250 300 350 400
Supply Voltage (V)
Frequency (MHz)
Figure 11. Offset Voltage vs. VCC
Figure 12. Offset Voltage vs. Frequency
1.35
Offset Voltage (V) .
Offset Voltage (V) .
1.24
1.23
1.22
1.21
1.3
1.25
1.2
1.15
1.2
1.1
3
3.1
3.2
3.3
3.4
3.5
3.6
0
50
Supply Voltage (V)
Figure 13. Output Voltage vs. VCC;
150
200
250
Figure 14. Output Voltage vs. Load Resistance;
1.45
1.45
VOUT+
1.35
Output Voltage (V) .
Output Voltage (V) .
100
Frequency (MHz)
1.25
1.15
VOUT-
1.05
0.95
1.35
VOUT+
1.25
1.15
VOUT-
1.05
0.95
3
3.1
3.2
3.3
3.4
3.5
3.6
80
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90
100 110 120 130 140 150
Load Resistance (Ω )
Supply Voltage (V)
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AS1156/AS1154
Data Sheet - Ty p i c a l O p e r a t i n g C h a r a c t e r i s t i c s
Figure 15. ICC vs. VCC
Figure 16. ICC vs. Temperature;
.
13
10.6
Supply Current (mA)
Supply Current (mA)
.
11
10.2
9.8
9.4
9
3
3.1
3.2
3.3
3.4
3.5
12
Freq = 100MHz
11
10
Freq = 20MHz
9
8
-50
3.6
Supply Voltage (V)
-30
-10
10
30
50
70
90
Ambient Temperature(°C)
Figure 17. Short Circuit Current vs. VCC
Figure 18. ICC vs. Frequency
18
Output Short Circuit Current (mA)
.
3.9
16
Supply Current (mA)
.
3.85
3.8
3.75
3.7
3.65
14
Two Channels
12
One Channel
10
8
6
4
2
3.6
0
3
3.1
3.2
3.3
3.4
3.5
0
3.6
Supply Voltage(V)
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50
100
150
200
250
Frequency (MHz)
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AS1156/AS1154
Data Sheet - D e t a i l e d D e s c r i p t i o n
8 Detailed Description
LVDS Interface
The LVDS interface standard is a signaling method intended for point-to-point communication over a controlled-impedance medium as defined by the ANSI/TIA/EIA-644 and IEEE 1596.3 standards. The LVDS standard uses a lower voltage swing than other common communication standards, achieving higher data rates with reduced power
consumption while reducing EMI emissions and system susceptibility to noise.
The AS1156/AS1154 is an 800Mbps single/dual differential LVDS driver that is designed for high-speed, point-to-point,
low-power applications. This device accepts LVTTL/LVCMOS input levels and translates them to LVDS output signals.
The AS1156/AS1154 generates a 2.5mA to 4.5mA output current using a current-steering configuration. This current
steering approach induces less ground bounce and no shoot-through current, enhancing noise margin and system
speed performance. The driver outputs are short-circuit current limited, and enter a high-impedance state when the
device is not powered or is disabled.
The current-steering architecture of the AS1156/AS1154 requires a resistive load to terminate the signal and complete
the transmission loop. Because the device switches current and not voltage, the actual output voltage swing is determined by the value of the termination resistor at the input of an LVDS receiver (AS1157, AS1158). Logic states are
determined by the direction of current flow through the termination resistor.
With a typical 3.7mA output current, the AS1156/AS1154 produces an output voltage of 370mV when driving a 100Ω
load.
Termination
Because the AS1156/AS1154 is a current-steering device, no output voltage will be generated without a termination
resistor. The termination resistors should match the differential impedance of the transmission line. Output voltage levels depend upon the value of the termination resistor.
The AS1156/AS1154 is optimized for point-to-point interface with 100Ω termination resistors at the receiver inputs. Termination resistance values may range between 90 and132Ω, depending on the characteristic impedance of the transmission medium.
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AS1156/AS1154
Data Sheet - A p p l i c a t i o n s
9 Applications
Table 5. Function Table
Input
Output
INx
OUTx+
OUTx-
L
L
H
H
H
L
0.8V < VINx < 2.0V
Undetermined
Undetermined
Figure 19. Typical Application Circuit
+3.3V
+3.3V
0.001µF
0.001µF
0.1µF
0.1µF
LVDS
Signals
LVTTL/LVCMOS
Data Inputs
Tx
107Ω
Rx
LVTTL/LVCMOS
Data Outputs
AS1158
Single LVDS Receiver
AS1156
100Ω Shielded Twisted Cable or Microstrip PC Board Traces
Power-Supply Bypassing
To bypass VCC, use high-frequency surface-mount ceramic 0.1µF and 0.001µF capacitors in parallel as close to the
device as possible, with the smaller valued capacitor closest to pin VCC.
Differential Traces
Input trace characteristics can adversely affect the performance of the AS1156/AS1154.
„
Use controlled-impedance PC board traces to match the cable characteristic impedance. The termination resistor is
also matched to this characteristic impedance.
„
Eliminate reflections and ensure that noise couples as common mode by running the differential traces near each
other.
„
Reduce skew by using matched trace lengths. Tight skew control is required to minimize emissions and proper data
recovery of the devices.
„
Route each channel’s differential signals very close to each other for optimal cancellation of their respective external magnetic fields. Use a constant distance between the differential traces to avoid irregularities in differential
impedance.
„
Avoid 90° turns (use two 45° turns).
„
Minimize the number of vias to further prevent impedance irregularities.
Cables and Connectors
Supported transmission media include printed circuit board traces, backplanes, and cables.
„
Use cables and connectors with matched differential impedance (typically 100Ω) to minimize impedance mismatches.
„
Balanced cables such as twisted pair offer superior signal quality and tend to generate less EMI due to magnetic
field canceling effects. Balanced cables pick up noise as common mode, which is rejected by the LVDS receiver.
„
Avoid the use of unbalanced cables such as ribbon cable or simple coaxial cable.
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AS1156/AS1154
Data Sheet - A p p l i c a t i o n s
Board Layout
The device should be placed as close to the interface connector as possible to minimize LVDS trace length.
„
Keep the LVDS and any other digital signals separated from each other to reduce crosstalk.
„
Use a four-layer PC board that provides separate power, ground, LVDS signals, and input signals.
„
Isolate the input LVDS signals from each other and the output LVCMOS/LVTTL signals from each other to prevent
coupling.
„
Separate the input LVDS signals from the output signals planes with the power and ground planes for best results.
Figure 20. Driver Propagation Delay and Transition Time Waveforms
1.5V
1.5V
tPLHD
tPHLD
INx
VOH
OUTx0 Differential
0
OUTx+
VOL
80%
0
80%
VDIFF = (VOUTx+) - (VOUTx-)
00
20%
20%
tTLH
tTHL
Figure 21. Driver Propagation Delay and Transition Time Test Circuit
OUTx+
Generator
CL
RL
50Ω
OUTx-
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AS1156/AS1154
Data Sheet - A p p l i c a t i o n s
Figure 22. Driver VOD and VOS Test Circuit
OUTx+
RL/2
VCC
INx
VOS
VOD
GND
RL/2
OUTx-
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AS1156/AS1154
Data Sheet - P a c k a g e D r a w i n g s a n d M a r k i n g s
10 Package Drawings and Markings
The AS1156/AS1154 is available in a 8-pin SOIC package.
Figure 23. 8-pin SOIC Package
Notes:
1. Lead coplanarity should be 0 to 0.10mm (.004”) max.
2. Package surface finishing:
- Top, matte (charmilles #18-30)
- All sides, matte (charmilles +18-30)
- Bottom, smooth or matte (charmilles +18-30)
3. All dimensions excluding mold flashes and end flash from the package body shall not exceed 0.25mm (.010”) per side.
4. Details of pin #1 mark are optional but must be located within the
area indicated.
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Symbol
A
A1
A2
B
C
D
E
e
H
h
L
α
ZD
Min
Max
1.52
1.72
0.10
0.25
1.37
1.57
0.36
0.46
0.19
0.25
4.80
4.98
3.81
3.99
1.27BSC
5.80
6.20
0.25
0.50
0.41
1.27
0º
8º
0.53REF
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AS1156/AS1154
Data Sheet - O r d e r i n g I n f o r m a t i o n
11 Ordering Information
Part Number
Description
Delivery Form
Package
AS1156-BSOU
Single Channel LVDS Line Driver
Tubes
SOIC-8
AS1156-BSOT
Single Channel LVDS Line Driver
Tape and Reel
SOIC-8
AS1154-BSOU
Dual Channel LVDS Line Driver
Tubes
SOIC-8
AS1154-BSOT
Dual Channel LVDS Line Driver
Tape and Reel
SOIC-8
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AS1156/AS1154
Data Sheet
Copyrights
Copyright © 1997-2008, austriamicrosystems AG, Schloss Premstaetten, 8141 Unterpremstaetten, Austria-Europe.
Trademarks Registered ®. All rights reserved. The material herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written consent of the copyright owner.
All products and companies mentioned are trademarks or registered trademarks of their respective companies.
Disclaimer
Devices sold by austriamicrosystems AG are covered by the warranty and patent indemnification provisions appearing
in its Term of Sale. austriamicrosystems AG makes no warranty, express, statutory, implied, or by description regarding
the information set forth herein or regarding the freedom of the described devices from patent infringement. austriamicrosystems AG reserves the right to change specifications and prices at any time and without notice. Therefore,
prior to designing this product into a system, it is necessary to check with austriamicrosystems AG for current information. This product is intended for use in normal commercial applications. Applications requiring extended temperature
range, unusual environmental requirements, or high reliability applications, such as military, medical life-support or lifesustaining equipment are specifically not recommended without additional processing by austriamicrosystems AG for
each application. For shipments of less than 100 parts the manufacturing flow might show deviations from the standard
production flow, such as test flow or test location.
The information furnished here by austriamicrosystems AG is believed to be correct and accurate. However,
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consequential damages, of any kind, in connection with or arising out of the furnishing, performance or use of the technical data herein. No obligation or liability to recipient or any third party shall arise or flow out of
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Contact Information
Headquarters
austriamicrosystems AG
A-8141 Schloss Premstaetten, Austria
Tel: +43 (0) 3136 500 0
Fax: +43 (0) 3136 525 01
For Sales Offices, Distributors and Representatives, please visit:
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