Texas Instruments PurePath CC85XXDK, Руководство пользователя

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6.4 Buttons and LEDs
On the CC85xx Headset board there is a rocker switch and 2 LEDs to be used for “human
interaction”. This switch actually has 5 positions i.e. IN, UP, DOWN, HALFWAY UP and HALFWAY
DOWN, but the positions HALFWAY UP and HALFWAY DOWN are not in use. This can also be
seen from the schematic (Appendix A). Table 1 shows the button positions and the signals they
assert, as well as out-of-the-box functionality tied to these signals.
Table 1: Human interaction signal mapping
Button position CC85xx pin Out-of-the-box functionality
IN CSN Pairing button and power toggling
UP GIO1 Slave: volume up, Master: no function
DOWN GIO3 Slave: volume down, Master: no function
HALFWAY UP NC -
HALFWAY DOWN NC -
LED (D2) is connected to the CC85xx pin GIO12, and the intended usage of this diode is as a
network status LED. For details on how to configure the network LED please see the PurePath
Wireless Configurator [4]. The other LED (D3) is connected to the charger IC BQ25015 (for more
details see section 6.2).
6.5 RF Performance
The CC85xx Headset board does not have the output connected to a SMA connector, it is only
connected to an inverted F antenna. However, the output power measured into a 50 0hm load as
shown in Figure 6, is approximately 9 dBm. Please note that the supply voltage of the board is
approximately 2.15V. Note that to achieve maximum output power the supply voltage of the board
must be raised from 2.15V to 3.3V. This can be done by changing the ratio between the BQ25015
feedback resistors according to eq 8 in the BQ25015 datasheet [14]. The audio link is sustained for
input signals above -87dBm. Hence, a total link budget of 96 dB can be archived with the CC85xx
Headset board.
Finally, the design is pre-scanned for ETSI and FCC compliance, and the CC85xx Headset board
is suitable to fulfill these specifications.