Device Overview

General Description

The BAL-0026 is a broadband balun, featuring high isolation and is hand-tuned for optimal phase and amplitude balance over a 300 kHz to 26.5 GHz bandwidth. It serves as an excellent choice for analog to digital converters, balanced receivers, baseband digital modulations, and signal integrity enhancement.

Photo of BAL-0026

Features

  • 2:1 Impedance Ratio
  • 300 kHz to 26.5 GHz Balun (Balanced to Unbalanced Balun Transformer
  • Termination insensitive: Particularly suited to testing poorly matched or non-50 Ω devices or for extending 2 port VNAs for differential testing

Applications

  • Analog to Digital Converters
  • Balanced Receivers
  • Baseband Digital Modulation
  • Signal Integrity

Functional Block Diagram

Block Diagram

Part Ordering Options

Part NumberDescriptionConnectorsGreen StatusProduct LifecycleExport Classification
BAL-0026Broadband Isolation Balun (300KHz to 26.5GHz)Standard

REACH

RoHS

ReleasedEAR99

Table Of Contents

Revision History

Revision CodeRevision DateComment
-2014-01-01Datasheet initial Release
A2016-01-01Typical Performance Plots Updated
B2019-10-01Mixed Mode Scattering Parameters added
C2019-11-01RoHS Compliant assembly
D2020-07-01Specs Table Update
E2020-10-01Specs Table Update

Rev: E | Copyright © 2014, 2016, 2019 - 2020 Marki Microwave LLC.

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Port Configuration and Functions

Port Functions

PortFunctionConnector TypeDescriptionDC Equivalent
Circuit
0° Port (Balanced)0° Port SMAFThe 0° port is DC connected to the common port through a resistor and to ground through a resistor.Equivalent circuit for the 0° Port
180° Port (Balanced)180° Port SMAFThe 180° port is DC shorted to ground.Equivalent circuit for the 180° Port
Common Port (Unbalanced)RF Input SMAFThe common port is DC connected to the 0° port through a resistor and to ground through a resistor.Equivalent circuit for the RF Input

Rev: E | Copyright © 2014, 2016, 2019 - 2020 Marki Microwave LLC.

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Specifications

Absolute Maximum Ratings

ParameterMaximum RatingUnit
RF Power Handling 1W

Package Information

ParameterDetailsRating
Weight-127g
Dimensions-91.44 x 27.94 mm

Rev: E | Copyright © 2014, 2016, 2019 - 2020 Marki Microwave LLC.

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Electrical Specifications

Specifications guaranteed from -55 to +100°C, measured in a 50Ω system.

ParameterTest ConditionsMinimum
Frequency
(GHz)
Maximum
Frequency
(GHz)
MinTypMaxUnit
Amplitude Balance -0.0003 26.5-0.51.2dB
Common Mode Rejection -0.0003 26.52230-dB
Group Delay -0.0003 26.5-520-ps
Insertion Loss as a Mode Converter -0.0003 26.5-2.54.5dB
Isolation -1 26.5-24-dB
Nominal Phase Shift -0.0003 26.5-180-°
Phase Balance -0.0003 26.5-310°
Risetime/Falltime 1-0.0003 26.5-7.5-ps
RMS Group Delay Ripple -0.0003 26.5-8.2-ps
VSWR (Input) -0.0003 26.5-1.5-
VSWR (Output) -0.0003 26.5-1.55-
Impedance Ratio -- --2:1-

[1] Specified as 90%/10%. Calculated from Tau_balun2 = (Tau_out2 – Tau_in2)

Rev: E | Copyright © 2014, 2016, 2019 - 2020 Marki Microwave LLC.

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Typical Performance

Insertion Loss (dB) graph for BAL-0026
Return Loss (dB) graph for BAL-0026
Amplitude Balance (dB) graph for BAL-0026
Phase Balance (degree) graph for BAL-0026
Common Mode Rejection (dB) graph for BAL-0026
Isolation (dB) graph for BAL-0026
Band 1 Group Delay (ps) graph for BAL-0026
Differential Group Delay (ps) graph for BAL-0026

Rev: E | Copyright © 2014, 2016, 2019 - 2020 Marki Microwave LLC.

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Low Frequency Insertion Loss (dB) graph for BAL-0026

Rev: E | Copyright © 2014, 2016, 2019 - 2020 Marki Microwave LLC.

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Time Domain Performance Plots

Low frequency 1MHz square wave input graph for BAL-0026
Low frequency oscilloscope measurement of a 1MHz square wave input. Blue is 0° port output, pink is 180° port output. Note the amplitude divergence due to slight high pass roll off near DC. graph for BAL-0026
Oscilloscope measurements of the BAL-0026 with a 40 Gb/s PRBS pattern in single ended-to-differential mode. Eye diagrams are taken with a 231-1 PRBS input demonstrating minimal eye distortion/closure afforded by the extremely low frequency operation of the balun (<300 kHz). graph for BAL-0026
Oscilloscope measurements of the BAL-0026 with a 28 Gb/s PRBS pattern. Bit pattern is measured with a 27-1 PRBS input demonstrating extremely good pulse fidelity for both differential-to-single ended and single ended to differential mode conversions. Apparent baseline wander in differential-to-single ended is due to low pass filtering by test cables. graph for BAL-0026

Rev: E | Copyright © 2014, 2016, 2019 - 2020 Marki Microwave LLC.

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Mixed Mode Scattering Parameters

Mixed mode scattering parameters are used to characterize differential circuits. For baluns, this means that the 0° and 180° ports become a single 100Ω differential port and the common port remains the same 50Ω common port. The two-port s-parameters of the balun are then characterized based on differential (d), common mode (c), or single-ended (s) signals. For example: S12ds is the differential output response given a single ended input.

S11dd graph for BAL-0026
S11dc graph for BAL-0026
S12ds graph for BAL-0026
S11cd graph for BAL-0026
S11cc graph for BAL-0026
S12cs graph for BAL-0026

Rev: E | Copyright © 2014, 2016, 2019 - 2020 Marki Microwave LLC.

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S21sd graph for BAL-0026
S21sc graph for BAL-0026
s22ss graph for BAL-0026

Rev: E | Copyright © 2014, 2016, 2019 - 2020 Marki Microwave LLC.

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Mechanical Data

Rev: E | Copyright © 2014, 2016, 2019 - 2020 Marki Microwave LLC.

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