BCM88335 Data Sheet
Bluetooth Power Management Unit
Table 4 describes the power-control handshake signals used with the UART interface.
Table 4: Power Control Pin Description
Signal
Mapped to Pin
Type Description
BT_DEV_WAKE BT_GPIO_0
I
Bluetooth device wake-up: Signal from the host to the
BCM88335 indicating that the host requires attention.
•
Asserted: The Bluetooth device must wake-up or remain
awake.
•
Deasserted: The Bluetooth device may sleep when sleep
criteria are met.
The polarity of this signal is software configurable and can be
asserted high or low.
BT_HOST_WAK BT_GPIO_1
E
O
O
Host wake up. Signal from the BCM88335 to the host
indicating that the BCM88335 requires attention.
•
•
Asserted: host device must wake-up or remain awake.
Deasserted: host device may sleep when sleep criteria
are met.
The polarity of this signal is software configurable and can be
asserted high or low.
CLK_REQ
BT_CLK_REQ_OUT
WL_CLK_REQ_OUT
The BCM88335 asserts CLK_REQ when either the
Bluetooth or WLAN block wants the host to turn on the
reference clock. The CLK_REQ polarity is active-high. Add
an external 100 kΩ pull-down resistor to ensure the signal is
deasserted when the BCM88335 powers up or resets when
VDDIO is present.
Note: Pad function Control Register is set to 0 for these pins. See “DC Characteristics” on page 89 for more
details.
Broadcom®
September 23, 2015 • 88335-DS100-R
Page 37
BROADCOM CONFIDENTIAL
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