Bluetooth for $15

Cambridge Consultants has taken the wraps off a reference design for a Bluetooth cordless telephony access point featuring a bill of materials of under $15.

The new design is targeted at an exciting emerging market being pioneered by BT in Europe with its ‘Bluephone’ initiative, and attracting the attention of many other telcos and virtual network operators around the world.

It supports the concept of mobile handsets with Bluetooth being used as more versatile ‘three-way’ devices: making calls on the cellular network when roaming, but when at home or in range of an access point, using Bluetooth for a cordless connection to the fixed network, or as an intercom to other devices.

Cambridge Consultants’ design is offered as a reference design ready for manufacture or adaptation – complete with schematics, PCB files, and software – for a one-off license fee or per-unit royalties.

The Bluetooth telephony access point is built around a single-chip BlueCore2 device and its on-chip XAP microcontroller, with a power amplifier to achieve Class 1 performance and support a range of 100 meters (108 yards).

The design uses external Flash memory for the application program, and an external codec for the Bluetooth-to-PSTN interface.

The $15 bill of materials can be reduced even further by migrating the design to a BlueCore device with integral ROM and codec, once a product concept is proven. The design can be implemented on a PCB measuring 40x58mm (~1.6 x 2.3 inches).

The application software in the demonstrator implements three Bluetooth Profiles: cordless telephony, hands-free, and headset. A dialler application running on a PDA or phone platform can also be added, for use with a headset.

Other Profiles may be added easily, depending on an OEM’s product requirements.