Model 3A425 Rev. C Xinger Balun 50Ω to 25Ω Balanced Description The 3A425 is a low profile balanced to unbalanced transformer designed for pushpull amplifiers in an easy to use surface mount package covering GSM, D-AMPS and NMT900 applications. These compact Xinger® surface mount baluns are ideal for high volume manufacturing and are more reliable and repeatable than traditional baluns. The 3A425 has an unbalanced port impedance of 50Ω and balanced port impedances of 25Ω to ground with a 50Ω balance between outputs. This eases the matching of the push-pull amplifier’s power transistors, which have low impedance levels. The output ports have equal amplitude (-3dB) with 180 degree phase differential. The Xinger® balun is a result of years of research and development culminating with a solution so unique, a patent is pending on the design approach. The 3A425 is available on tape and reel for pick and place high volume manufacturing. ELECTRICAL SPECIFICATIONS*** Features: • • • • • • • • • • • 800 – 1000 MHz 180° Transformer 50 Ohm to 25 Ohm Broad Band Low Insertion Loss High Power Even Order Harmonic Suppression Input to Output DC Isolation Surface Mountable Tape & Reel Convenient Package Frequency Unbalanced Port Impedance Balanced Port Impedance* Return Loss Insertion Loss** MHz Ohms Ohms dB min dB max 800 - 1000 50 25 15 0.35 Amplitude Balance Phase Balance Power Handling ΘJC dB max Degrees max Watts ºC / Watt ºC 0.4 180+ 5.0 250 5.3 -55 to +85 Operating Temp. ***Specification based on performance of unit properly installed on microstrip printed circuit boards with 50 Ω nominal impedance. Specifications subject to change without notice. **Insertion Loss excludes reflected power. * 25Ω reference to ground Outline Drawing .750±.010 [19.05±0.25] Bottom View (Far-side) Side View Top View (Near-side) .076±.008 [1.93±0.20] Pin 2 .031±.004 TYP [0.80±0.10] .060±.008 [1.52±0.20] Pin 2 .027±.004 [0.69±0.10] .121±.004 [3.07±0.10] GND .790±.010 [20.07±0.25] Pin 1 Denotes Array Number .122±.008 [3.10±0.20] .401±.008 [10.19±0.20] Pin 3 Pin 3 Dimensions are in Inches [Millimeters] 3A425 Mechanical Outline Available on Tape and Reel For Pick and Place Manufacturing. .040±.008 [1.02±0.20] .035±.004 TYP [0.89±0.10] USA/Canada: Toll Free: Europe: (315) 432-8909 (800) 544-2414 +44 2392-232392 Model 3A425 Rev. C Typical Performance: 600 MHz. to 1200 MHz. Return Loss 3A425 0 0.75 -5 0.5 -10 R eturn Loss [dB ] Am plitude Balance [dB] Amplitude Balance 3A425 1 0.25 0 -0.25 -15 -20 -25 -0.5 -30 -0.75 -35 -1 600 700 800 900 1000 1100 -40 600 1200 700 800 -0.05 -172 -0.1 -174 -0.15 -0.2 -0.25 -0.3 -0.35 1000 1100 1200 -180 -182 -184 -186 -188 900 1200 -178 -0.45 800 1100 -176 -0.4 700 1000 Phase Balance 3A425 -170 Phase Balance [Degrees] Insertion Loss [dB] Insertion Loss 3A425 0 -0.5 600 900 Frequency [MHz] Frequency [MHz] 1000 1100 1200 -190 600 700 800 Frequency [MHz] 900 Frequency [MHz] Pin Configuration: Mounting Configuration: To ensure proper electrical and thermal performance there must be a ground plane with 100% solder connection underneath the part Multiple plated thru holes to ground 50 Ω Transmission Line .121 [3.07] .070 [1.78] .280 [7.11] .531 [13.48] .130 [3.30] .651 [16.54] .049 [1.24] .034 TYP [0.86] Dimensions are in Inches [Millimeters] 3A425 Rev A Mounting Footprint USA/Canada: Toll Free: Europe: (315) 432-8909 (800) 544-2414 +44 2392-232392 Available on Tape and Reel For Pick and Place Manufacturing. 2 Places 25 Ω Transmission Line Referenced to GND