LI254
Product Datasheet
25G 4-Channel BER Tester
LiBERT’s breakthrough BERT Tester delivers the industry’s most comprehensive
testability with highly integrated functions and ease of test handling
The LI254 is a comprehensive BER test system which is
specially designed for 100GBASE-SR4/LR4 QSFP28
transceiver module or AOC to perform BER test. Other
related 100GBASE protocols or 40GBASE application
are also available for BER test. The LI254 is comprised
of 4x 25G PPG, 4x 25G Error Detectors (ED) and single
one universal clock sources for all channels. With highly
integrated technology the LI254 can drive 4 channels TX
and test 5 channels RX BER performance of QSFP28
transceiver module/AOC in the same time. The high
speed interfaces are equipped with K-type 40GHz
connectors to generate PRBS signal from PPG and
receive PRBS signal from DUT then measuring BER as
ED. The LI254 is multi-lane designed system and can
efficiently increase test throughput on manufacturing
QSFP28 transceiver module or AOC. All lanes of LI254
have universal clock thus making users a great assist in
testing eye diagram on one high speed scope.
Features
4 channel 25G BERT with single one
universal clock source
27.9525/25.7813/10.3125Gbps multi data
rate for QSFP28/QSFP+ 4 lanes
application.
110/220V AC standard power supply
USB interface
Applications
100GBASE-SR4/LR4/ER4 QSFP28 TRx
Module/AOC BER Tester
40GBASE-SR4/LR4 BER Tester
10GBASE-SR/LR/ER BERT Test
Product picture above is 4-channel BERT with 1-channel trigger. LiBERT reserves right
to change case version in necessity
Product Spec
Confidential
2015, 05, 27 REV 01
WWW.Li-BERT.COM
PAGE 1
LI254
Product Datasheet
<System Block Diagram>
K-Type
40GHz
K-Type
40GHz
K-Type
40GHz
PRBS TX+/PRBS TX+/PRBS TX+/-
K-Type
40GHz
PRBS TX+/-
K-Type
40GHz
PMD RX+/-
K-Type
40GHz
PMD RX+/-
K-Type
40GHz
PMD RX+/PMD RX+/-
K-Type
40GHz
USB
25/10G PPG
HighSpeedSignal
25/10G PPG
25/10G PPG
Clock Gen
ClockSignal
25/10G PPG
Optional for individual
or universal clock source
TriggerSignal
25/10G PPG
25/10G PPG
Clock/Trigger
SMA
25/10G PPG
25/10G PPG
<General Description>
The LI254 is an outstanding BER Test system comprising of 25G PRBS Pattern Generator and 25G Error
Detector (ED). With LiBERT’s innovative integration technology LiBERT multi channels BERT provide user
an easy test environment without so much complicated test setup.
The 25G PPG are PRBS Pattern Generator (PPG) can drive DUT module with high speed PRBS pattern.
There are three voltage amplitudes to be selected and the test pattern is selectable by PRBS 2^7, PRBS 2^9,
PRBS 2^15, PRBS 2^23 or PRBS 2^31 under 25GBASE/10GBASE signal rate. For more other multi-rate
operation or other more signal rate choice, please contact us.
The 10G ED are Error Detector can receive DUT module with high speed PRBS pattern. There are many
modes to monitor BER and the test pattern is selectable by PRBS 2^7, PRBS 2^9, PRBS 2^15, PRBS 2^23 or
PRBS 2^31 under 25GBASE/10GBASE signal rate depending on PPG operation mode.
There is single one clock source provided from synthesizer circuitry and can synchronize 4 channel BERTs
hence providing one clock signal to trigger scope to make test setup easier or provide monitor clock signal for
industrial application.
Product Spec
Confidential
2015, 05, 27 REV 01
WWW.Li-BERT.COM
PAGE 2
LI254
Product Datasheet
<LI254 Feature>
Lighten and simplify QSFP28/QSFP+ test setup by LiBERT’s innovative and outstanding technique of
highly integration BERT function, making test cycle time much of reduction and hence increase
throughput.
The PPG and ED are 25G/10G PRBS pattern generator and error detector system which can drive DUT
by 25G/10G high speed PRBS signal and analyze BER.
Operating with universal synthesizer clock source, all channels of BERTs can synchronize and user can
monitor eye performance in one high speed scope by using only one trigger.
<Optical-Electro Specification>
Recommend Operating Condition
Parameter
Conditions/Remarks
Signal Rate
Supply Voltage
Supply Current
Ambient Operating Temp
BERT Interface Form Factor
Clock Form Factor
O/E Characteristic
Parameter
PPG Channel
PPG Data Rate
PPG Output Voltage
PPG Output Signal Pattern
PPG Output Impedance
PPG High Speed Output
ED Channel
ED LS Data Rate
ED Input Voltage
ED ED Input Impedance
ED CDR
ED High Speed Input
BERT Clock Source
Product Spec
Min
Typ
Max
Unit
27.9525/25.7813/10.3125
90
110/220
264
1.5
2
0
+30
+50
K-TYPE Connector with 40GHz Bandwidth
SMA Connector with 18GHz Bandwidth
Gbps
Vac
A
°C
3 Data rates
AC Power Supply
Conditions/Remarks
Min
Typ
Max
Unit
4
Ch
3 Data rates
27.9525/25.7813/10.3125
Gbps
AC-coupled, Differential
500
mVpp
Selectable for PRBS 2^7/ PRBS 2^9/ PRBS 2^15/ PRBS 2^23/PRBS 2^31
100
ohm
AC coupled with high speed K-TYPE 40GHz connector
4
Ch
3 Data rates
27.9525/25.7813/10.3125
Gbps
AC-coupled Differential BER at
20
mVpp
BER 10-12
100
ohm
Specific for 25G/10G Application
AC coupled with high speed K-TYPE 40GHz connector
One universal clock for entire system and speed under 4G signal rate
Confidential
2015, 05, 27 REV 01
WWW.Li-BERT.COM
PAGE 3
LI254
Product Datasheet
<Graphical User Interface >
Above GUI is an example that LiBERT provides as standard GUI for users to operate easily
for each product. Users can simply choose signal data rate, signal PRBS pattern and other
parameters for each of 4 channels PPG to enable PPG function, and also can test BER with
timing setting. For more detail software control and support, please contact sales@li-bert.com
Product Spec
Confidential
2015, 05, 27 REV 01
WWW.Li-BERT.COM
PAGE 4
LI254
Product Datasheet
<Order Information>
Item
Module Name
BERT System
Part Number
Description
LI254
4CH 25G/10G BER Tester
1
25G/10G BERT
LIB-254-4IS
25G/10G BERT with PPG and ED. 4channel of
25G/10G BERT make up LI254
2
Synthesizer
LIC-254-4IS
System synthesizer to provide single universal clock
for 4channel of 25G/10G BERT
3
Power_CtrL
LIP-254-4IS
Power circuitry and control core for system
operating
4
LI254 Mainframe
LI254-001
System mainframe and all module are installed
insides this mainframe.
Product Spec
Confidential
2015, 05, 27 REV 01
WWW.Li-BERT.COM
PAGE 5