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Attach the UART to USB cable J14 as described in Section 6.1.2. Once the desired current measurement
equipment is connected to the Eval board, apply power to the board.
Use of the Radio Control Tool (RCT), Section 6, will control the Evaluation board to set the BT4 IP block into
either continuous Tx, continuous Rx or into standby or sleep modes for current measurements in the desired
modes of operation.The RCT can also be used to vary the regulator output from 1.0 to 1.65 volts. Please see the
Radio Control Tool User’s Guide for more information.
Please also note than when using the RCT, both the USB to USB cable and the USB to UART cable must
be installed between the PC and the Eval board. Note the correct position of the Power Control jumper
(J47) to enable RCT control of the voltage regulator. (See Section 3.3.1).
If you are using a current probe connected to an oscilloscope and wish to view the current drain while the Eval
board is operating in a standa
rd Bluetooth application, we recommend you place the board into “Beacon Demo”
mode as described in Section 3.3.5. The power profile curve displayed on the scope should look similar to Figure
5.2b below.
Figure 5.2b
– 1 volt Power Profile in Beacon Broadcast mode
The diagram above shows
the Eval board’s power consumption in 1 volt mode while configured as a Beacon.
The current beacon interval in the demo firmware is 1 second. The diagram shows the beacon coming out of deep
sleep, broadcasting or “Advertising” on each of the 3 advertising channels and then going back into deep sleep
mode again for the remaining 995 mSeconds. You will notice a receive scan event on each channel just after the
Tx event. Tx power draining can be seen at ~7.2 mA (or 7.2mW since we are running at 1.0 volts). Rx current
consumption is ~6.8mW while deep sleep is ~800nW. The average Standby current during the initial wake-up time
and also between channel scans averages about 800uW. Please not that during the first 30 seconds after board
power up or a reset event, you may see additional Tx and Rx pulses as the board may be trying to connect to near
by Bluetooth devices. After 30 sections, the beacon will enter a “non-connectable state and you will only see these
3 Tx events. For more information on t
his connectable or “discoverable” stateplease refer to Section 3.5.2. This
type of measurement can also be taken in 3 volt mode as described in the next section.