1
FEATURES
400.0 Mbps low jitter fully differential data path
200MHz clock channel
3.3 V power su pply
10mA LVDS output drivers
Cold sparing all pins
Fast propagation delay of 3.5ns max
Receiver input threshold < + 100 mV
Radiation-hardened design; total dose irradiation testing to
MIL-STD-883 Method 1019
- Total-dose: 300 krad(Si) and 1 Mrad(Si)
- Latchup immune (LET > 100 MeV-cm2/mg)
Packaging options:
- 48-lead flatpack
Standard Microcircuit Drawing 5962-01536
- QML Q and V compliant part
Compatible with ANSI/TIA/EIA 644-1995 L VDS Standard
INTRODUCTION
The UT54LVDM328 is an Octal Bus Repeater utilizing Low
Voltage Differential Signaling (LVDS) technolog y for low
power, high speed operation. Data paths are fully differential
from input to output for low noise generation and low pulse
width distortion. L VDS I/O enable high speed data transmission
for point-to point or multi-drop inte rconnects. This device is
designed for use as a high speed differential repeater.
The UT54LVDM328 is a repeater designed specifically for the
bridging of multiple backplanes in a system. The
UT54LVDM328 utilizes low voltage differential signaling to
deliver high speed while consuming minim al power with
reduced EMI. The UT54LVDM328 repeats signals between
backplanes and accepts or drives signals onto the local bus.
The individual LVDS outputs can be put into Tri-State by use
of the enable pins.
All pins have Cold Spare buffers. These buffers will be high
impedance when VDD is tied to VSS.
OUT1+
END
IN1+ +
-
OUT2+
IN2+ +
-
IN1- OUT1-
OUT2-
IN2-
Standard Products
UT54LVDM328 Octal 400 Mbps Bus LVDS Repeater
Data Sheet
August, 2002
Figure 1a. UT54LVDM328 Repeater Block Diagram
(Partial - see Page 2 for complete diagram)
2
OUT1+
END
IN1+ +
-
OUT2+
IN2+ +
-
IN1- OUT1-
OUT2-
IN2-
OUT3+
IN3+ +
-
OUT4+
IN4+ +
-
IN3- OUT3-
OUT4-
IN4-
OUT5+
IN5+ +
-
OUT6+
IN6+ +
-
IN5- OUT5-
OUT6-
IN6-
OUT7+
IN7+ +
-
OUT8+
IN8+ +
-
IN7- OUT7-
OUT8-
IN8-
Clk In+ Clk Out+
+
-
Clk In- Clk Out-
ENCK
Figure 1b. UT54LVDM328 Repeater Diagram
3
PIN DESCRIPTION
Figure 2. UT54LVDM328 Pinout
UT54LVDM328
Bus Repeater
48
47
46
45
44
43
42
41
OUT3+
1IN1+
2
3
4
5
6
7
8IN3-
9
10
11
12
13
14
15
16
IN3+
CLK In+
CLK In-
IN5-
17
18
19
20
21
22
23
24
IN6-
VSS
IN8+
IN8-
OUT1+
VDD
40
39
38
37
36
35
34
33
CLK OUT-
OUT5-
VDD
CLK OUT+
32
31
30
29
28
27
26
25 OUT8-
OUT6+
OUT7+
IN1-
IN2-
VDD
IN4+
IN4-
ENCK
END
IN5+
IN6+
VDD
IN7+
IN7-
OUT1-
OUT2+
OUT2-
VSS
OUT3-
OUT4+
OUT4-
VSS
OUT5+
VSS
OUT6-
VDD
OUT7-
OUT8+
IN2+
VSS
Name # of Pins Description
INn+ 8Non-inverting LVDS input
INn- 8Inverting LVDS input
OUTn+ 8Non-inverting LVDS output
OUTn- 8Inverting LVDS Output
END 1A logic low on the enable puts
the LVDS data output into Tri-
State and reduces the supply
current
ENCK 1A logic low on the enable puts
the LVDS clock output into Tri-
State and reduces the supply
current
VSS 5Ground
VDD 5Power supply
CLK IN+ 1Non-Inverting Clock LVDS
Input
CLK IN- 1Inverting clock LVDS Input
CLK
OUT+ 1Non-Inverting Clock LVDS
Output
CLK
OUT- 1Inverting Clock LVDS Output
4
APPLICATIONS INFORMATION
The UT54LVDM328 provides the basic bus repeater
function. The device operates as a 9 channel LVDS buffer.
Repeating the signal restores the LVDS amplitude, allowing
it to drive another media segment. This allows for isolation
of segments or long distance applications.
The intended application of these devices and signaling
technique is for both point-to-point baseband (single
termination) and multipoint (double termination) data
transmissions over controlled impedance media. The
transmission media may be printed-circuit board traces,
backplanes, or cables. (Note: The ultimate rate and distance
of data transfer is dependent upon the attenuation
characteristics of the media, the noise coupling to the
environment, and other application specific characteristics.)
Input Fail-Safe:
The UT54LVDM328 also supports OPEN, shorted and
terminated input fail-safe. Receiver output will be HIGH for
all fail-safe conditions.
PCB layout and Power System Bypass:
Circuit board layout and stack-up for the UT54LVDM328
should be designed to provide noise-free power to the device.
Good layout practice also will 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 (4 to 10 mils) for power/ground sandwiches. This
increases the intrinsic capacitance of the PCB power system
which improves power supply filtering, especially 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 0.01µF to
0.1µ F. Tantalum capacitors may be in the range of 2.2µF to
10µF. Voltage rating for tantalum capacitors should be at
least 5X the power supply voltage being used. It is
recommended practice to use two vias at each power pin of
the UT54LVDM328, as well as all RF bypass capacitor
terminals. Dual vias reduce the interconnect inductance and
extends the effective frequency range of the bypass
components.
The outer layers of the PCB may be flooded with additional
ground plane. These planes will improve shielding and
isolation, as well as increase the intrinsic capacitance of the
power supply plane system. Naturally, to be effective, these
planes must be tied to the ground supply plane at frequent
intervals with vias. Frequent via placement also improves
signal integrity in signal transmission lines by providing short
paths for image currents which reduces signal distortion. The
planes should be pulled back from all transmission lines and
component mounting pads a distance equal to the width of
the widest transmission line from the internal power or
ground plane(s) whichever is greater. Doing so minimizes
effects on transmission line impedances and reduces
unwanted parasitic capacitances at component mounting
pads.
Compatibility with LVDS standard:
In backplane multidrop configurations, with closely spaced
loads, the effective differential impedance of the line is
reduced. If the mainline has been designed for 50Ω
differential impedance, the loading effects may reduce this
to the 35Ω range depending upon spacing and capacitance
load. Terminating the line with a 35Ω load is a better match
than with 50Ω and reflections are reduced.
5
ABSOLUTE MAXIMUM RATINGS1
(Referenced to VSS)
Notes:
1. Stresses outside the listed absolute maximum ratings may cause permanent damage to the device. This is a stress rating only, and functional operation of the device
at these or any other conditions beyond limits indicated in the operational sections of this specification is not recommended. Exposure to absolute maximum rating
conditions for extended periods may affect device reliability and performance.
2. Maximum junction temperature may be increased to +175°C during burn-in and life test.
3. Test per MIL-STD-883, Method 1012.
4. For cold spare mode (VDD = VSS), VI/O may be -0.3V to the maximum recommended operating VDD +0.3V.
RECOMMENDED OPERATING CONDITIONS
SYMBOL PARAMETER LIMITS
VDD DC supply voltage -0.3 to 4.0V
VI/O Voltage on any pin -0.3 to (VDD + 0.3V)
TSTG Storage temperature -65 to +150°C
PDMaximum power dissipation 800mW
TJMaximum junction temperature 2+150°C
ΘJC Thermal resistance, junction-to-case322°C/W
IIDC input current ±10mA
SYMBOL PARAMETER LIMITS
VDD Positive supply voltage 3.3 to 3.6V
TCCase temperature range -55 to +125°C
VIN DC input voltage, receiver inputs 0 to 2.4V
DC input voltage, logic inputs 0 to VDD for END or ENCK
6
DC ELECTRICAL CHARACTERISTICS 1
(VDD = 3.3V + 0.3V; -55°C < TC < +125°C)
SYMBOL PARAMETER CONDITION MIN MAX UNIT
CMOS/TTL DC SPECIFICATIONS (EN)
VIH High-level input voltage 2.0 VDD V
VIL Low-level input voltage GND 0.8 V
IIH High-level input current VIN=3.6V; VDD = 3.6V -10 +10 µA
IIL Low-level input current VIN=0V; VDD = 3.6V -10 +10 µA
VCL Input clamp voltage ICL
=-18mA -1.5 V
ICS Cold Spare Leakage current VIN=3.6V, VDD=VSS -20 +20 µΑ
LVDS OUTPUT DC SPECIFICATIONS (OUT+, OUT-)
VOD Differential Output Voltage RL= 35Ω (See Figure 9) 250 450 mV
∆VOD Change in VOD between
complimentary output states RL= 35Ω (See Figure 9) 35 mV
VOS Offset Voltage 1.055 1.550 V
∆VOS Change in VOS between complimentary
output states RL=35Ω35 mV
IOZ Output Tri-State Current Tri-State output, VDD = 3.6V
VOUT=VDD or GND
+10 µΑ
ICSOUT Cold Sparing Leakage Current VOUT=3.6V, VDD=VSS -20 +20 µΑ
IOS2,3 Output Short Circuit Current VOUT+ OR VOUT = 0 V -25 mA
LVDS RECEIVER DC SPECIFICATIONS (IN+, IN-)
VTH3Differential Input High Threshold VCM = +1.2V +100 mV
VTL3Differential Input Low Threshold VCM = +1.2V -100 mV
VCMR Common Mode Voltage Range VID=210mV 0.2 2.00 V
IIN Input Current VIN = +2.4V, VDD = 3.6V -10 +10 µΑ
VIN = 0V, VDD = 3.6V -10 +10 µΑ
ICSIN Cold Sparing Leakage Current VIN=3.6V, VDD=VSS -20 +20 µΑ
RL= 35 Ω VOS=(VOH+VOL)
2
7
DC ELECTRICAL CHARACTERISTICS 1 (CON"T)
Notes:
1. Current into device pins is defined as positive. Current out of device pins is defined as negative. All voltages are referenced to ground.
2. Output short circuit current (IOS
) is specified as magnitude only, minus sign indicates direction only. Only one output should be shorted at a time, do not exceed
maximum junction temperature specification.
3. Guaranteed by characterization.
SYMBOL PARAMETER CONDITION MIN MAX UNIT
Supply Current
ICCL Total Supply Current RL = 35Ω
END, ENCK= VDD, VDD= 3.6V
220 ma
ICCZ Tri-State Supply Current END, ENCK = VSS, VDD= 3.6V 20 ma
8
AC SWITCHING CHARACTERISTICS
(VDD = +3.3V + 0.3V, TA = -55 °C to +125 °C)
Notes:
1. Guaranteed by design.
2. Guaranteed by characterization.
.
SYMBOL PARAMETER Conditions MIN MAX UNIT
tPHZ2Disable Time (Active to Tri-State) High to Z
(See Figure 7) RL= 35 Ω, CL = 10pf 4.5 ns
tPLZ2Disable Time (Active to Tri-State) Low to Z
(See Figure 7) RL= 35 Ω, CL = 10pf 4.5 ns
tPZH2Enable Time (Tri-State to Active) Z to High
(See Figure 7) RL= 35 Ω, CL = 10pf 11.0 ns
tPZL2Enable Time (Tri-State to Active) Z to Low
(See Figure 7) RL= 35 Ω, CL = 10pf 11.0 ns
tLHT1Output Low-to-High Transition Time, 20% to 80%
(See Figures 4 and 5) RL= 35 Ω, CL = 10pf 600 ps
tHLT1Output High-to-Low Transition Time, 80% to 20%
(See Figures 4 and 5) RL= 35 Ω, CL = 10pf 600 ps
tPLHD Propagation Low to High Delay
(See Figures 4 and 6) RL= 35 Ω, CL = 10pf 3.5 ns
TPHLD Propagation High to Low Delay
(See Figures 4 and 6) RL= 35 Ω, CL = 10pf 3.5 ns
TSKEW Differential Skew TPHLD - TPLHD
(See Figures 4 and 6)
900 ps
TCCS Output Channel-to-Channel Skew
(See Figures 4 and 6) 500 ps
9
R
RIN+
Pulse
Generator
50Ω
Figure 4. LVDS Output Load
RIN-
50ΩCL
D
CL
RL
tHLT
20%
80%
0V
20%
80%
tLHT
Figure 5. LVDS Output Transition Time
VDIFF
tPLHD tPHLD
Vdiff = 0V
Vdiff = 0V
IN
OUT
Figure 6. Propagation Delay Low-to-High and High-to-Low
10
EN
tPLZ tPZL
50% 50%
VOL
0VDiff
0VDiff
VOH
VDD
VDD/2
VDD/2
50%
tPZH
tPHZ
Figure 7. Output active to TRI-STATE and TRI-STATE to active
50%
OUT
OUT
TCCS
Vdiff = 0V
Vdiff = 0V
OUT 0
OUT 1
Figure 8. Output Channel-to-Channel Skew
Figure 9. Driver VOD
and VOS Test Circuit or Equivalent Circuit
D
DIN
DOUT-
DOUT+
20pF
Driver Enabled
Generator
50Ω
RL = 35ΩVOD
20pF
11
PACKAGING
Notes:
1. All exposed metalized areas are gold plated over electroplated nickel per MIL-PRF-38535.
2. The lid is electrically connected to VSS.
3. Lead finishes are in accordance to MIL-PRF-38535.
4. Package dimensions and symbols are similar to MIL-STD-1835 Requirement 101, Configuration B.
5. Lead position and coplanarity are not measured.
6. ID mark symbol is vendor option.
7. With solder, increase maximum by 0.003. Figure 10. 48-pin Flatpack
12
ORDERING INFORMATION
UT54LVDM328 Bus LVDS Repeater:
UT 54LVDM328 - * * * * *
Device Type:
UT54LVDM328 Bus LVDS Repeater
Access Time:
Not applicable
Package Type:
(U) = 48-lead Flatpack (dual-in-line)
Screening:
(C) = Military Temperature Range flow
(P) = Prototype flow
Lead Finish:
(A) = Hot solder dipped
(C) = Gold
(X) = Factory option (gold or solder)
Notes:
1. Lead finish (A,C, or X) must be specified.
2. If an “X” is specified when ordering, then the part marking will match the lead finish and will be either “A” (solder) or “C” (gold).
3. Prototype flow per UTMC Manufacturing Flows Document. Tested at 25°C only. Lead finish is GOLD ONLY. Radiation neither
tested nor guaranteed.
4. Military Temperature Range flow per UTMC Manufacturing Flows Document. Devices are tested at -55°C, room temp, and 125°C.
Radiation neither tested nor guaranteed.
13
UT54LVDM328 Bus LVDS Repeater: SMD
5962 - * * *
Federal Stock Class Designator: No Options
Total Dose
(R) = 1E5 rad(Si)
(F) = 3E5 rad(Si)
(G) = 5E5 rad(Si)
(H) = 1E6 rad(Si)
Drawing Number: 01536
Device Type
01 = Bus LVDS Repeater
Class Designator:
(Q) = QML Class Q
(V) = QML Class V
Case Outline:
(Y) = 48-lead Flatpack (dual-in-line)
Lead Finish:
(A) = Hot solder dipped
(C) = Gold
(X) = Factory Option (gold or solder)
**
01536
Notes:
1.Lead finish (A,C, or X) must be specified.
2.If an “X” is specified when ordering, part marking will match the lead finish and will be either “A” (solder) or “C” (gold).
3.Total dose radiation must be specified when ordering. QML Q and QML V not available without radiation hardening.
14
NOTES
