BC41B143A-DS-001PE Datasheet, PDF (90/102 Pages) List of Unclassifed Manufacturers – BlueCpre 4-ROM Single Chip Bluetooth v2.0 System with EDR

Solder Profiles
13 Solder Profiles
The soldering profile depends on various parameters necessitating a set up for each application. The data here is
given only for guidance on solder re-flow. The four zones are described in Table 13.1
Preheat Zone
Equilibrium Zone
Reflow Zone
Cooling Zone
This zone raises the temperature at a controlled rate, typically 1-2.5°C/s.
This zone brings the board to a uniform temperature and also activates the
flux. The duration in this zone (typically 2-3 minutes) will need to be adjusted
to optimise the out gassing of the flux.
The peak temperature should be high enough to achieve good wetting but
not so high as to cause component discoloration or damage. Excessive
soldering time can lead to intermetallic growth which can result in a brittle
joint
The cooling rate should be fast, to keep the solder grains small which will
give a longer lasting joint. Typical rates will be 2-5°C/s.
Table 13.1: Soldering Profile Zones
13.1 Solder Re-Flow Profile for Devices with Lead-Free Solder Balls
Composition of the solder ball: Sn 95.5%, Ag 4.0%, Cu 0.5%
Lead Free Reflow Solder Profile 2
300
250
200
150
100
50
0
0
50
100
150
200
250
300
350
400
450
500
Time (s)
Figure 13.1: Typical Lead-Free Re-flow Solder Profile
BC41B143A-ds-001Pe
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Production Information
© Cambridge Silicon Radio Limited 2005
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