BCM43455XKUBGT Datasheet, PDF (43/159 Pages) Cypress Semiconductor – Single-Chip 5G WiFi IEEE 802.11ac MAC/Baseband/ Radio with Integrated Bluetooth 4.1 and FM Receiver

BCM43455 Preliminary Data Sheet
Bluetooth Power Management Unit
Figure 7 shows the startup signaling sequence prior to software download.
Figure 7: Startup Signaling Sequence Prior to Software Download
LPO
VDDIO
HostResetX
Host IOs unconfigured
Host IOs configured
T1
BT_DEV_WAKE
BT_REG_ON
T2
BTH IOs unconfigured
BTH IOs configured
BT_HOST_WAKE
BT_UART_CTS_N
BT_UART_RTS_N
T3
Host side drives this line
low
T4
BTH device drives this line low
indicating transport is ready
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.
Broadcom^®
November 5, 2015 • 43455-DS109-R
BROADCOM CONFIDENTIAL
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