User Manual
Table Of Contents
- Introduction
- Features
- Table of Contents
- 1. Ordering Information and Module Marking
- 2. Block Diagram
- 3. Pinout and Package Information
- 4. Electrical Characteristics
- 5. Power Management
- 6. Clocking
- 7. CPU and Memory Subsystem
- 8. WLAN Subsystem
- 9. Bluetooth Low Energy 4.0
- 10. External Interfaces
- 11. Application Reference Design
- 12. Module Outline Drawings
- 13. Design Consideration
- 14. Reflow Profile Information
- 15. Module Assembly Considerations
- 16. Regulatory Approval
- 17. Reference Documentation
- 18. Document Revision History
- The Microchip Web Site
- Customer Change Notification Service
- Customer Support
- Product Identification System
- Microchip Devices Code Protection Feature
- Legal Notice
- Trademarks
- Quality Management System Certified by DNV
- Worldwide Sales and Service
Temperature Profiling
Temperature profiling must be performed for all new board designs by attaching thermocouples at the
solder joints, on the top surface of the larger components, and at multiple locations of the boards. This is
to ensure that all components are heated to a temperature above the minimum reflow temperatures and
the smaller components do not exceed the maximum temperature limit. The SnAgCu solder alloy melts at
~217°C, so the reflow temperature peak at joint level must be 15 to 20°C higher than melting
temperature. The targeted solder joint temperature for the SnAgCu solder must be ~235°C. For larger or
sophisticated boards with a large mix of components, it is also important to ensure that the temperature
difference across the board is less than 10 degrees to minimize board warpage. The maximum
temperature at the component body must not exceed the MSL3 qualification specification.
14.5.1 Reflow Oven
It is strongly recommended that a reflow oven equipped with more heating zones and Nitrogen
atmosphere must be used for the lead-free assembly. The Nitrogen atmosphere is shown to improve the
wet-ability and reduce temperature gradient across the board. It can also enhance the appearance of the
solder joints by reducing the effects of oxidation.
The following items must also be observed in the reflow process:
1. Some recommended pastes include:
– NC-SMQ
®
230 flux and Indalloy
®
241 solder paste made up of 95.5 Sn/3.8 Ag/0.7 Cu
– SENJU N705-GRN3360-K2-V Type 3, no clean paste
2. Allowable reflow soldering iterations:
– Three times based on the following reflow soldering profile (see, following figure).
3. Temperature profile:
– Reflow soldering must be done according to the following temperature profile (see, following
figure).
– Peak temperature: 250°C
ATWINC3400-MR210CA
© 2017 Microchip Technology Inc.
Draft Datasheet Preliminary
DS00000000A-page 42