Technical Characteristics of a Bluetooth Device
Original Post: technical enquiry!!! (SIG Forum)
Date: 2000-05-04
Technical Details on Bluetooth chips can be hard to get,
and varies between vendors,below is some of the typical details of Bluetooth
devices.
Bluetooth devices generally are either a one chip solution
or multiple chip (2 or 3). This is due to the fact that a bluetooth device (or
module) consist generally of three main parts:
- the RF part,
- the baseband processor and
- the link manager (also a CPU core, e.g. a 8 or 16 bit RISC).
In addition you have to have RAM and non volatile memory
(e.g. flash memory). Some vendors will produce BT module in multiple chip (2 or
3 chip), e.g. the RF on a chip, the others on another. Some other vendors take
the one-chip solution.
For the one chip solution,the following info can be given
for reference from a particular vendor:
| Package: |
81 ball BGA, 8mm x 8mm |
| Supply Voltage: |
2.7 - 3.3V |
| Power Consumption: |
Data Transmitting (@4dBm): typ 41mA |
| Voice Only Connection |
15mA for HV3 packets, 30mA for HV1 |
| R1 Page Scanning: |
420uA |
| Inquiry Scanning + R1 Page Scanning: |
560uA |
| Park mode (1 second interval): |
120uA |
| Standby state: |
10uA |
Dimensions of a Bluetooth device can be a bit more
difficult to establish. Especially as you also need an antenna, a flash
module and a crystal to run your application. All of the components (the chip,
the antenna, the memory and the crystal) could be placed on a PCB about 20mm x
15mm. The thickness of the chip mentioned above is about 1.25mm (min) or 1.55mm
(max).
Power & Current issues also need to be addressed.
What is needed to be calculated is the overall current the device would need in
a circuit , such that it can work in normal operation for a long time, (we must
also take into account the BT device is portable, and not connected to a mains).
A current drawn of less than 300mA may be enough for a BT module to
operate actively. Assuming a BT device used two AA Ni-Cd batteries with 600mAh,
it could operate actively for up to 2 hours.
|
