Model 3A412S Rev A Balun Transformers 50 to 12.5 Balanced Description The 3A412S is a low profile balanced to unbalanced transformer designed for pushpull amplifiers in an easy to use surface mount package for AMPS and GSM. These compact Xinger surface mount baluns are ideal for high volume manufacturing and are more reliable and repeatable than traditional baluns. The 3A412S has an unbalanced port impedance of 50 and balanced port impedances of 12.5 to ground with a 25 balance between outputs. This eases the matching of the pushpull 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 3A412S is available on tape and reel for pick and place high volume manufacturing. ELECTRICAL SPECIFICATIONS*** Features: * * * * * * * * * * * 800 - 1000 MHz 180 Transformer 50 Ohm to 2 x 12.5+j Ohm Low Insertion Loss High Power Even Order Suppression Input to Output DC Isolation Surface Mountable Tape & Reel Convenient Package Lead Free Frequency Unbalanced Port Impedance Balanced Port Impedance* Return Loss Insertion Loss MHz Ohms Ohms dB min dB max 800-1000 50 12.5+j 15 0.48 869-894 50 12.5+j 15 0.35 925-960 50 12.5+j 15 0.40 Amplitude Balance Phase Balance Power Handling JC dB max Degrees max Watts C / Watt C 0.40 0.40 0.40 180 5.0 180 5.0 180 5.0 250 250 250 3.8 3.8 3.8 -55 to +85 -55 to +85 -55 to +85 ***Specification based on performance of unit properly installed on microstrip printed circuit boards with 50 nominal impedance. Specifications subject to change without notice. **Insertion Loss excludes reflected power. * 12.5 reference to ground Outline Drawing Top View (Near-side) Pin 2 Operating Temp. 1.000.010 [25.400.25] Side View .075.008 [1.910.20] Pin 3 .750.010 [19.050.25] GND Pin 1 Denotes Array Number Bottom View (Far-side) .060.004 [1.520.10] Pin 3 .050.008 [1.270.20] .070.008 [1.780.20] Pin 2 .030.004 TYP [0.760.10] .030.004 [0.760.10] GND .400.004 [10.160.10] .050.008 [1.270.20] Pin 1 .358.008 [9.090.20] .115.004 [2.920.10] Dimensions are in Inches [Millimeters] 3A412S Mechanical Outline Available on Tape and Reel For Pick and Place Manufacturing. USA/Canada: Toll Free: Europe: (315) 432-8909 (800) 544-2414 +44 2392-232392 Model 3A412S Rev A Typical Performance: 700 MHz. to 1100 MHz. Return Loss 3A412S Amplitude Balance 3A412S 0 0.5 0.4 -10 0.2 Return Loss [dB] Amplitude Balance [dB] 0.3 0.1 0 -0.1 -0.2 -20 -30 -0.3 -0.4 -40 -0.5 700 800 900 1000 700 1100 900 Frequency [MHz] Insertion Loss 3A412S Phase Balance 3A412S 1000 1100 1000 1100 -170 0 Phase Balance [Degrees] -0.1 Insertion Loss [dB] 800 Frequency [MHz] -0.2 -0.3 -0.4 -0.5 700 800 900 1000 1100 -175 -180 -185 -190 700 800 900 Frequency [MHz] 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 .410 [10.41] .050 [1.27] .034 [0.86] 2 Places 12.5 Transmission Line Referenced to GND .080 [2.03] .030 [0.76] .075 [1.90] .080 [2.03] .650 [16.51] .291 [7.40] .070 [1.78] Multiple plated thru holes to ground Dimensions are in Inches [Millimeters] 3A412S 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. .030 TYP [0.76] .115 [2.92] 50 Transmission Line