The following are the technical characters of a Bluetooth device:
The devices are either a one chip solution or multiple chips in general. Blue tooth device has three main parts – RF, baseband processor and link manager (could be a CPU core like 8 or 16 bit Reduced Instruction Set Computer. A BT module in multiple chips, usually 2 or 3 chip, like RF on a chip are produced by certain vendors.
For a single chip solution, the following information can be used for referencing from a particular vendor.

Package :  81 ball BGA, 8mm x 8mm
Supply Voltage : 2.7 – 3.3v
Power Consumption : Data transmitting @ 4dBm – type 41mA
Voice Only Connection : 15mA for HV3 packets, 30mA for HV1
RI Page Scanning : 420uA
Inquiry Scanning + RI Page Scanning : 560uA
Park mode (1 second interval)  : 120uA
Standby state  : 10uA

The components, the chip, memory and the crystal, antenna could be placed on a PCB about 20mm x 15mm. The thickness of the chip is about 1.25mm or 1.55 mm..   _{Your Comment}