SHF Communication Technologies AG
Wilhelm-von-Siemens-Str. 23D • 12277 Berlin • Germany
Phone +49 30 772051-0 • Fax +49 30 7531078
E-Mail: sales@shf.de • Web: http://www.shf.deDatasheet
SHF 651 ALimiting Amplifier

SHF reserves the right to change specifications and design without notice – SHF 651 A - V002 – April 03, 2012

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Description
The SHF 651 A Limiting Amplifier operates at data rates up to 56 Gbps and with clock signal up to 40
GHz for use in broadband test setups and telecom transmission systems. The AC-coupled differential
inputs can be driven single ended as well by terminating the unused input. For input signals >150 mV theoutput voltage will be clipped to 650 mV.

Features
•
••••
••
•

Supports data rates up to 56 GBit/s
Supports clock frequencies up to 40 GHz
Fast signal rise and fall times: < 8 ps
Low power consumption: 650 mW
Single-ended or differential input drive
Differential output, 650 mV single ended output swing
Bias Board
Output Level ControlApplications•••

100G Ethernet development and prototyping
OC-768 / STM-256 applicationsTelecom transmission••

Fibre Channel
Broadband test and measurement equipment®

Block diagram®

Fibre Channel is a registered trademark of the Fibre Channel Industry Association

SHF reserves the right to change specifications and design without notice – SHF 651 A - V002 – April 03, 2012

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Bias Board
At delivery, the bias board is mounted on a common base plate, together with the SHF 651 A Limiting
Amplifier. When using the bias board only one supply voltage of -5V needs to be applied; all operating
voltages will be provided by the bias board.
With the factory settings all bias voltages are set to optimum / maximum output voltage. However, if
required the customer can adjust the output level “LVL” and the input data bias voltages “DB1” and “DB2”with the appropriate trim potentiometers on the bias board.
For system applications it is possible to remove the bias board. In that case the operating voltages haveto be supplied by the customer’s circuitry.

Output Level Control “LVL”
Data Bias Adjust “DB1”Data inv. Bias Adjust “DB2”
Not Used-5V

SHF reserves the right to change specifications and design without notice – SHF 651 A - V002 – April 03, 2012

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Specifications
Parameter

Unit

Symbol

Min.

Typ.

Max.

Minimum Data Rate

Gbps

Rin,minMaximum Data Rate

Gbps

Rin,max

Input Amplitude

mVpp

Vin

Input Sensitivity

mVpp

Vin

8050mV

Vout

580

650

900

fs

Jrms

500

800

dB

Gp

2022

Supply Voltage

VVee-5.2-5-4.8

Supply Current

mA

Iee

130

150mW

Pd650

Output Level Adjust

VLVL

-3.3

Input Data Bias

VDB1-3.3-1,650Input inv. Data Bias

VDB2-3.3-1,650°C

Tambient

15Comment

Input Parameters
150561000
See page 9

Output Parameters
Output Amplitude
Output Jitter, RMS value

1Small Signal Gain

Single ended,adjustable up to -3dB

Tambient=25°C

Power Requirements

Power Dissipation@ VEE = -5V;
incl. Bias Board

Bias Voltages0

if not used, connect tognd

Conditions
Operating Temperature

135

Test condition: Input Signal JitterRMS = 280 fs

SHF reserves the right to change specifications and design without notice – SHF 651 A - V002 – April 03, 2012

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Typical Output Eye Diagrams
31The measurements shown below had been performed using a SHF 12103 A BPG (PRBS 2 -1), an Agilent
86100D DCA with Precision Time Base Module (86107A) and 70 GHz Sampling Head (86118A). The outputsof the Limiting Amplifier had been connected directly to the DCA input.

Input @ 60 Gbps

Input @ 56 Gbps

Output @ 60 Gbps

Output @ 56 Gbps

Output inv. @ 60 Gbps

Output inv. @ 56 Gbps

SHF reserves the right to change specifications and design without notice – SHF 651 A - V002 – April 03, 2012

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Input @ 50 Gbps

Input @ 43 Gbps

Output @ 50 Gbps

Output @ 43 Gbps

Output inv. @ 50 Gbps

Output inv. @ 43 Gbps

SHF reserves the right to change specifications and design without notice – SHF 651 A - V002 – April 03, 2012

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Input @ 32 Gbps

Input @ 28 Gbps

Output @ 32 Gbps

Output @ 28 Gbps

Output inv. @ 32 Gbps

Output inv. @ 28 Gbps

SHF reserves the right to change specifications and design without notice – SHF 651 A - V002 – April 03, 2012

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Input @ 25 Gbps

Input @ 16 Gbps

Output @ 25 Gbps

Output @ 16 Gbps

Output inv. @ 25 Gbps

Output inv. @ 16 Gbps

SHF reserves the right to change specifications and design without notice – SHF 651 A - V002 – April 03, 2012

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Typical Results
31

The measurements shown below had been performed using a SHF 12103 A BPG (PRBS 2 -1), aSHF 11100 A Error Analyzer, an Agilent 86100D DCA with Precision Time Base Module (86107A) and a
70 GHz Sampling Head (86118A) to determine the output amplitude. In case of the sensitivity-9measurement the input signal had been reduced until a BER limit of <10 had been achieved.

Sensitivity [mV]

Data Input Sensitivity
1009080706050403020100051015202530354045505560

Bit Rate [Gbps]

Compression of data signals in single ended drive
Output Amplitude [mV]

700
600
500
400
300
200
10000100

200

300

400

500

Input Amplitude [mV]

Output amplitude in single ended drive (sinusoidal input)
Output amplitude [mV]

800
700
600
500
400300input amplitude = 30mV

200

input amplitude = 100mV

100input amplitude = 200mV

005101520253035404550Frequency [GHz]SHF reserves the right to change specifications and design without notice – SHF 651 A - V002 – April 03, 2012

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Typical S-Parameters

Aperture of Group Delay measurement: 100 MHz
SHF reserves the right to change specifications and design without notice – SHF 651 A - V002 – April 03, 2012

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Outline Drawing

2345

9,19,1

1

GND
3,85,08
4 x 5,084x Ø2,7InOut29In

1.85mm (V) female

In

1.85mm (V) female

Y

1.85mm (V) female

Y

1.85mm (V) female

PinDesignation

1Level (LVL)

2

Data Bias 1 (DB1)

3Data Bias 2 (DB2)

4nc

5-5V

19

SHF AG Berlin-5V

3

LVL DB1 DB2

3Connector

OutXXXXX

19PortLimiting
Amplifier35

In293835

SHF 651 A

2834
40
52,512,3

5,08
9,719,512,3

SHF reserves the right to change specifications and design without notice – SHF 651 A - V002 – April 03, 2012

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