X2A2020RFDCT Datasheet, PDF (4/4 Pages) AVX Corporation – The MLOTM SMT RF-DC Crossover is a very low profile crossover that intersects an RF and DC circuit trace in an SMT package.

MLO^TM RF-DC SMT Crossover
AUTOMATED SMT ASSEMBLY
The following section describes the guidelines for
automated SMT assembly of MLO^TM RF devices which are
typically Land Grid Array (LGA) packages or side termination
SMT packages.
Control of solder and solder paste volume is critical for
surface mount assembly of MLO^TM RF devices onto the
PCB. Stencil thickness and aperture openings should be
adjusted according to the optimal solder volume. The
following are general recommendations for SMT mounting
of MLO^TM devices onto the PCB.
SMT REFLOW PROFILE
Common IR or convection reflow SMT processes shall be
used for the assembly. Standard SMT reflow profiles, for
eutectic and Pb free solders, can be used to surface mount
the MLO^TM devices onto the PCB. In all cases, a
temperature gradient of 3°C/sec, or less, should be
maintained to prevent warpage of the package and to
ensure that all joints reflow properly. Additional soak time
and slower preheating time may be required to improve the
out-gassing of solder paste. In addition, the reflow profile
depends on the PCB density and the type of solder paste
used. Standard no-clean solder paste is generally
recommended. If another type of flux is used, complete
removal of flux residual may be necessary. Example of a
typical lead free reflow profile is shown below:
Tp
T_L
Ts max
Ts min
25
Ramp-up
tp
tL
Critical Zone
TL to Tp
ts
Preheat
Ramp-down
t 25ºC to Peak
Time
Profile Parameter
Ramp-up rate (Tsmax to Tp)
Preheat temperature (Ts min to Ts max)
Preheat time (ts)
Time above TL, 217ºC (tL)
Peak temperature (Tp)
Time within 5ºC of peak temperature (tp)
Ramp-down rate
Time 25ºC to peak temperature
Pb free, Convection, IR/Convection
3ºC/second max.
150ºC to 200ºC
60 – 180 seconds
60 – 120 seconds
260°C
10 – 20 seconds
4ºC/second max.
6 minutes max.
4