5 Reflow Profiles

The SOM is assembled using the IPC/JEDEC J-STD-020E-compliant reflow profile.

In addition to the initial assembly solder, we recommend a maximum of two additional soldering processes:
  • Assembly on the main board
  • Spare heating pass in case the SOM must be removed from the main board for analysis

The SOM can be soldered to the host PCB by using one of the standard SnAgCu or SnBi solder reflow profile. To avoid any damage to the SOM, follow the JEDEC recommendations as well as those listed below:
  • Do not exceed solder paste recommended peak temperature (Tp).
  • Refer to the solder paste data sheet for specific reflow profile recommendations.
  • Use no-clean flux solder paste.
  • Use only one flow. If the PCB requires multiple flows, mount the SOM at the time of the final flow.
Figure 5-1. Reflow Profile Example used for Soldering the System-On-Module on an Application Board
Table 5-1. Reflow Profile Parameters According To Solder Paste Used
SymbolProfile FeatureValue according to Solder Paste
Interflux DP 5600NC-SMQ 230
TsminPre-heat minimum temperature100°C 150°C
TsmaxPre-heat maximum temperature120°C 180°C
TL Liquidus temperatureRefer to solder paste manufacturer's recommendations (e.g. 139°C for Interflux DP 5600)Refer to solder paste manufacturer's recommendations (e.g. 220°C for NC-SMQ 230)
TPMaximum peak temperature190°C (must be comprised between 160°C and 190°C depending on the solder paste used)245°C (must be comprised between 230°C and 245°C depending on the solder paste used)
25 to TsminAmbient ramp-up rate1 to 3°C/sec. max.1 to 5°C/sec. max.
ts

(from Tsmin to Tsmax)

Temperature rise20 to 90 seconds30 to 90 seconds
Pre-heat ramp-up rate0.2°C to 1°C/sec. max.0.5°C to 1°C/sec. max.
Tsmax to TLSoak ramp-up rate1°C to 4°C/sec. max.1°C to 4°C/sec. max.
TL to TpPeak ramp-up rate1°C to 4°C/sec. max.1°C to 3°C/sec. max.
tLLiquidus temperature time maintained above TL 30 to 90 seconds60 to 150 seconds
tPTime (tP) within 5°C of the peak temperature (TP)15 seconds30 seconds
TP to TLRamp-down rate1°C to 4°C/sec. max.2°C to 6°C/sec. max.
–Time from 25°C to peak temperature3 minutes max.8 minutes max.