GT-tronics HK Ltd BC86XRPA 사용자 설명서
The above schematic shows a typical application of BC865RPA module with PIOs running at 1.8v. Double click
on the diagram to see the detail drawings.
Power supply
Power supply
The whole module shall be powered by a single cell 3.7v Li-ion rechargeable battery (VBAT, pin#34). A coupling
capacitor of 2.2uF should be placed as close to this pin as possible. The module will output 1.8v at VPAD (pin #9). All
PIO pins, SPI programming port and UART port will run at this power rail.
Differential Audio Outputs
PIO pins, SPI programming port and UART port will run at this power rail.
Differential Audio Outputs
The output stage digital circuitry converts the signal from 16-bit per sample, linear PCM of variable sampling frequency to
bit stream, which is fed into the analogue output circuitry. The output stage circuit comprises a DAC with gain setting and class AB
output stage amplifier. The output is available as a differential signal between SPK_LN and SPK_LP for the left channel, as the
schematic shows, and between SPK_RN and SPK_RP for the right channel. The output stage is capable of driving a speaker directly
when its impedance is at least 8Ω.
output stage amplifier. The output is available as a differential signal between SPK_LN and SPK_LP for the left channel, as the
schematic shows, and between SPK_RN and SPK_RP for the right channel. The output stage is capable of driving a speaker directly
when its impedance is at least 8Ω.
UART Port
BC865RPA has a standard UART serial interface that provides a simple mechanism for communicating with other serial
devices using the RS232 protocol. A typical application will be connecting to an external HCI host. When BC865RPA is connected
to another digital device, RX and TX transfer data between the 2 devices. UART configuration parameters, such as baud rate and
packet format, are set by configuration of the BC8645 ROM chip.
to another digital device, RX and TX transfer data between the 2 devices. UART configuration parameters, such as baud rate and
packet format, are set by configuration of the BC8645 ROM chip.
To communicate with the UART at its maximum data rate using a standard PC, an accelerated serial port adapter card is required for
the PC.
the PC.
Possible UART Settings
Parameter
Possible values
Minimum
1200 baud (≤2%Error)
Baud rate
Maximum
9600 baud (≤1%Error)
Parity
None, Odd or Even
Number of stop bits
1 or 2
Bits per byte
8
SPI Programming Port
The SPI is used to program and configure the ROM firmware inside BC8645 chip. It is required in production. Ensure the 4
SPI signals are brought out to either test points or a header. Note that these four signals will run at 1.8v power rail.
Mic Inputs
The microphone bias, MIC_BIAS, provides power to external mic circuitry, and is configurable from 1.8v to 2.4v. The
MIC_BIAS is like any voltage regulator and requires a minimum load to maintain regulation. The MIC_BIAS maintains regulation
within the limits 0.200mA to 1.230mA. The input impedance at MIC_A_N, MIC_A_P, MIC_B_N and MIC_B_P is typically
6.0kΩ
within the limits 0.200mA to 1.230mA. The input impedance at MIC_A_N, MIC_A_P, MIC_B_N and MIC_B_P is typically
6.0kΩ
.
LED Drivers
BC865RPA includes 2 pads dedicated to driving LED indicators. Both terminals can be controlled by firmware, The
terminals are open-drain outputs, so the LED must be connected from a positive supply rail to the pad in series with a current
limiting resistor. It is recommended that the LED pad, LED[0] or LED[1] pins, operate with a pad voltage below 0.5V. In this case,
the pad is like a resistor, RON . The resistance together with the external series resistor sets the current in the LED.
limiting resistor. It is recommended that the LED pad, LED[0] or LED[1] pins, operate with a pad voltage below 0.5V. In this case,
the pad is like a resistor, RON . The resistance together with the external series resistor sets the current in the LED.
Buttons
The example application has assigned the following functions to each PIO pins:
PIN
NAME
Function
Descriptions
13 PIO17
REV
Select previous song, fast rewind.
29 PIO21
FWD
Select next song, fast forward
14 PIO18
PLAY_PAUSE Play / pause toggle
18 PIO20
VOL-
Volume decrease
15 PIO19
VOL+
Volume decrease
33 VBAT_SENSE BAT_SENSE
Battery level detection
39 VREG
VREG_EN
Power on, sleep mode