How to enable the battery charger circuit of an Steval-Smartag2?

[aet001]

Based on User manual of Steval-Smartag2, it has an optional battery charger circuit based on STBC15.
However the SMD Components for STBC15 battery charger, haven't been attached as seen from the following photo:

Here is an Snapshot from the User Manual: 

Based on this STBC15QTR, BAT54SFILM, STL4P3LLH6, STL6N3LLH6 and some other components should be added. However I've little problem with attaching these SMD components. STBC15QTR can't be soldered with a standard soldering iron, as the connection pads are entirely underneath the chip. 

In the other hand using hot bed or reflow oven doesn't make sense, as they would damage other parts of Smartag2 (for example debuging pins)

I unfortunatly couldn't find any instructions for attaching theese SMD components. Now I am wondering What is ST:s official suggestion on, how these components should be attached? :)

[FCOLA.5 · Accepted solution]

Hello,

I confirm that the STBC15QTR cannot be soldered with a standard soldering iron, for this type of device, one of the following methods should be used:

• Hot‑air soldering, applying solder paste on the PCB and heating the component evenly until the alloy melts.
• Reflow soldering with stencil and solder paste, which is the recommended solution for production environments.

Both methods allow proper soldering of the bottom pads, which is not possible with a traditional tip soldering iron.

best regards,

Filippo

[aet001]

Hi

Thank you for the tips related to soldering.

I've a follow up question related to software side. I am planning to use STEVAL-25R3916B and STEVAL-SMARTAG2 as a combo and planning to transfer both data and power.

However as Antenna isn't able to transmit data and power at the same time. That's why I am planning to make an arrangement where connection is mainly used for power transfer, but every 5s power transfer is stopped to quickly transfer data. 

I couldn't find barely any information about software side of STEVAL-SMARTAG2 power transfer feature. Now I am wondering if there is documentation about controlling STBC15 or projects that's utilizes STEVAL-SMARTAG2 power transfer feature?