SC16C550B All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 6 — 16 December 2014 43 of 49
NXP Semiconductors
SC16C550B
5 V, 3.3 V and 2.5 V UART with 16-byte FIFOs
12.4 Reflow soldering
Key characteristics in reflow soldering are:
Lead-free versus SnPb soldering; note that a lead-free reflow process usually leads to
higher minimum peak temperatures (see Figure 28
) than a SnPb process, thus
reducing the process window
Solder paste printing issues including 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). In addition, the peak temperature must be 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 27
and 28
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 28
.
Table 27. SnPb eutectic process (from J-STD-020D)
Package thickness (mm) Package reflow temperature (C)
Volume (mm
3
)
< 350 350
< 2.5 235 220
2.5 220 220
Table 28. Lead-free process (from J-STD-020D)
Package thickness (mm) Package reflow temperature (C)
Volume (mm
3
)
< 350 350 to 2000 > 2000
< 1.6 260 260 260
1.6 to 2.5 260 250 245
> 2.5 250 245 245
SC16C550B All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 6 — 16 December 2014 44 of 49
NXP Semiconductors
SC16C550B
5 V, 3.3 V and 2.5 V UART with 16-byte FIFOs
For further information on temperature profiles, refer to Application Note AN10365
“Surface mount reflow soldering description”.
13. Soldering of through-hole mount packages
13.1 Introduction to soldering through-hole mount packages
This text gives a very brief insight into wave, dip and manual soldering.
Wave soldering is the preferred method for mounting of through-hole mount IC packages
on a printed-circuit board.
13.2 Soldering by dipping or by solder wave
Driven by legislation and environmental forces the worldwide use of lead-free solder
pastes is increasing. Typical dwell time of the leads in the wave ranges from
3 seconds to 4 seconds at 250 C or 265 C, depending on solder material applied, SnPb
or Pb-free respectively.
The total contact time of successive solder waves must not exceed 5 seconds.
The device may be mounted up to the seating plane, but the temperature of the plastic
body must not exceed the specified maximum storage temperature (T
stg(max)
). If the
printed-circuit board has been pre-heated, forced cooling may be necessary immediately
after soldering to keep the temperature within the permissible limit.
13.3 Manual soldering
Apply the soldering iron (24 V or less) to the lead(s) of the package, either below the
seating plane or not more than 2 mm above it. If the temperature of the soldering iron bit is
less than 300 C it may remain in contact for up to 10 seconds. If the bit temperature is
between 300 C and 400 C, contact may be up to 5 seconds.
MSL: Moisture Sensitivity Level
Fig 28. Temperature profiles for large and small components
001aac844
temperature
time
minimum peak temperature
= minimum soldering temperature
maximum peak temperature
= MSL limit, damage level
peak
temperature
SC16C550B All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 6 — 16 December 2014 45 of 49
NXP Semiconductors
SC16C550B
5 V, 3.3 V and 2.5 V UART with 16-byte FIFOs
13.4 Package related soldering information
[1] For SDIP packages, the longitudinal axis must be parallel to the transport direction of the printed-circuit
board.
[2] For PMFP packages hot bar soldering or manual soldering is suitable.
14. Abbreviations
Table 29. Suitability of through-hole mount IC packages for dipping and wave soldering
Package Soldering method
Dipping Wave
CPGA, HCPGA - suitable
DBS, DIP, HDIP, RDBS, SDIP, SIL suitable suitable
[1]
PMFP
[2]
- not suitable
Table 30. Abbreviations
Acronym Description
CMOS Complementary Metal-Oxide Semiconductor
CPU Central Processing Unit
DLL Divisor Latch LSB
DLM Divisor Latch MSB
DMA Direct Memory Access
FIFO First-In, First-Out
ISDN Integrated Service Digital Network
LSB Least Significant Bit
MSB Most Significant Bit
TTL Transistor-Transistor Logic
UART Universal Asynchronous Receiver and Transmitter

SC16C550BIB48,128

Mfr. #:
Manufacturer:
NXP Semiconductors
Description:
UART Interface IC 16CB 2.5V-5V 1CH UART 16B FIFO
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
T/T Paypal Visa MoneyGram Western Union