SA58672 Datasheet, PDF (23/27 Pages) NXP Semiconductors – 3.0 W mono class-D audio amplifier

NXP Semiconductors
SA58672
3.0 W mono class-D audio amplifier
• Solder paste printing issues, such as smearing, release, and adjusting the process
window for a mix of large and small components on one board
• Reflow temperature profile; this profile includes preheat, reflow (in which the board is
heated to the peak temperature), and cooling down. It is imperative that the peak
temperature is high enough for the solder to make reliable solder joints (a solder paste
characteristic) while being low enough that the packages and/or boards are not
damaged. The peak temperature of the package depends on package thickness and
volume and is classified in accordance with Table 8.
Table 8. Lead-free process (from J-STD-020C)
Package thickness (mm) Package reflow temperature (°C)
Volume (mm³)
< 350
350 to 2000
< 1.6
260
260
1.6 to 2.5
260
250
> 2.5
250
245
> 2000
260
245
245
Moisture sensitivity precautions, as indicated on the packing, must be respected at all
times.
Studies have shown that small packages reach higher temperatures during reflow
soldering, see Figure 19.
temperature
maximum peak temperature
= MSL limit, damage level
minimum peak temperature
= minimum soldering temperature
peak
temperature
MSL: Moisture Sensitivity Level
Fig 19. Temperature profiles for large and small components
time
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For further information on temperature profiles, refer to application note AN10365
“Surface mount reflow soldering description”.
15.3.1 Stand off
The stand off between the substrate and the chip is determined by:
• The amount of printed solder on the substrate
• The size of the solder land on the substrate
SA58672_4
Product data sheet
Rev. 04 — 8 June 2009
© NXP B.V. 2009. All rights reserved.
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