BCM89359 Advance Data Sheet
Bluetooth Power Management Unit
Figure 7: Startup Signaling Sequence
LPO
Host I/Os
unconfigured
VDDIO
Host I/Os
configured
T1
HostResetX
BT_DEV_WAKE
BT_REG_ON
BTH I/Os
unconfigured
T2
BTH I/Os
configured
BT_HOST_WAKE
BT_UART_CTS_N
T3
Host side drives
this line low
BTH device drives this line low
indicating transport is ready
T4
BT_UART_RTS_N
CLK_REQ_OUT
T5
Driven
Pulled
Notes:
T1 is the time for Host to settle it’s IOs after a reset.
T2 is the time for Host to drive BT_REG_ON high after the Host IOs are configured.
T3 is the time for BTH (Bluetooth) device to settle its IOs after a reset and reference clock settling time has elapsed .
T4 is the time for BTH device to drive BT_UART_RTS_N low after the Host drives BT_UART_CTS_N low. This assumes the BTH device has already
completed initialization.
T5 is the time for BTH device to drive CLK_REQ_OUT high after BT_REG_ON goes high. Note this pin is used for designs that use an external reference
clock source from the Host. This pin is irrelevant for Crystal reference clock based designs where the BTH device generates it’s own reference clock from
an external crystal connected to it’s oscillator circuit.
Timing diagram assumes VBAT is present.
BBC Power Management
The following are low-power operations for the BBC:
•
•
Physical layer packet-handling turns the RF on and off dynamically within transmit/receive packets.
Bluetooth-specified low-power connection modes: sniff, hold, and park. While in these modes, the
BCM89359 runs on the low-power oscillator and wakes up after a predefined time period.
•
A low-power shutdown feature allows the device to be turned off while the host and any other devices in the
system remain operational. When the BCM89359 is not needed in the system, the RF and core supplies
are shut down while the I/O remains powered. This allows the BCM89359 to effectively be off while keeping
the I/O pins powered so they do not draw extra current from any other devices connected to the I/O.
Broadcom®
September 9, 2014 • 89359-DS100-R
Page 34
BROADCOM CONFIDENTIAL
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