Recommendation on small and simple (and cheap?) BT4 module - Page 1
Forum section: electronics / projects

author: poorchava
author_rank: Super Contributor
timestamp: July 07, 2015, 06:39:26 pm
content: Hi,I have a project where i need BT4 connectivity. I have browsed the usual stored, but there seems to be really a lot of stuff available and I have hard time choosing, as I have little experience with BT.I need something that will pair with PC/laptop/smartphone out of the box using only UART or SPI interface that is well documented (for some reason like 3 out of 4 modules I see do not have any publicly available command set documentation). I do not want to purchase more programming/flashing/configuration hardware, as this would not only increase cost but also be pain in the ass during production. I also do not want torun application code on the BT module. Power consumption is a secondary matter. NDA required is fine if there is no way, but $1k+ devkits (looking at Z-Wave) or 100k MOQ are a show stopper (specialistic device, target annual volume in single hundreds of units).I need the module to be as small as possible doe to the compact form factor of the device. something along the lines of 15x20mm is an absolute maximum, I'd like it to be smaller if possible.Do you know of any candidates?

author: politoleo
author_rank: Newbie
timestamp: July 07, 2015, 07:14:06 pm
content: It looks like this one is what are you looking for (I have no experience with this module):http://na.industrial.panasonic.com/products/wireless-connectivity/bluetooth/bluetooth-smart-ready-multi-mode/series/pan1026-series/CS487

author: mark03
author_rank: Frequent Contributor
timestamp: July 08, 2015, 04:27:36 pm
content: I'm a fan of the BlueGiga modules (now part of Silabs). They are CC-based (TI) modules with firmware that gives you the option of a serial API, for control from a host MCU, or a high-level scripting language, for running simple applications inside the module.Their written documentation is only average (i.e. not very good), but their US-based support is top-notch, even if you're a small customer; I often received help within hours of asking. That would be the deciding factor for me.

author: poorchava
author_rank: Super Contributor
timestamp: July 08, 2015, 06:37:24 pm
content: Right now I have used the PAN1026 recommended before. One issue I have with it is the land-grid style footprint (with like half of the contacts being GND or NC) that will be a massive pain in the ass during prototyping (i somehow can't see mounting it correctly using hot-air...).Second candidate would be BC127, but it lacks EU-based distributor.

author: Unknown
author_rank: Unknown
timestamp: July 08, 2015, 07:42:10 pm
content: +1 for the PAN1026, if you have a reflow oven.Another good candidate might be the RN4020http://www.mouser.com/ds/2/268/50002279A-515512.pdf. In the past i have used the RN-42 ( bluetooth class 2.0) and it is very simple to solder and use.

author: poorchava
author_rank: Super Contributor
timestamp: July 08, 2015, 09:09:03 pm
content: I do have a reflow oven, but when I assemble the first prototype I usually do it piece by piece. I guess I could order a tiny stencil only for this part and then reflow it with other components already soldered on the board.The RN4020 is BLE only as far as I understand. According to some comms protocol estimations I need the EDR data rate, so BLE is not really good.The RN-42 at 25x13mm is too large.