BCM4330 Preliminary Data Sheet
Bluetooth Power Management Unit
Host Controller Power Management
When running in UART mode, the BCM4330 may be configured so that dedicated signals are used for power
management hand-shaking between the BCM4330 and the host. The basic power saving functions supported
by those hand-shaking signals include the standard Bluetooth defined power savings modes and standby
modes of operation.
Table 4 describes the power-control hand-shake signals used with the UART interface.
Table 4: Power Control Pin Description
Signal
Mapped to Pin
Type Description
BT_WAKE
BT_GPIO_0
I
Bluetooth device wake-up: Signal from the host to the
BCM4330 indicating that the host requires attention.
• Asserted: Bluetooth device must wake-up or remain
awake.
• Deasserted: Bluetooth device may sleep when sleep
criteria are met.
The polarity of this signal is software configurable and can be
asserted high or low.
HOST_WAKE
BT_GPIO_1
O
Host wake up. Signal from the BCM4330 to the host indicating
that the BCM4330 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.
BT_CLK_REQ_OUT BT_CLK_REQ_OUT O
The BCM4330 asserts CLK_REQ when Bluetooth or WLAN
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 BCM4330
powers up or resets when VDDIO is present.
Note: Pad function Control Register is set to 0 for these pins. See “Muxed Bluetooth GPIO Signals” on page 113
for details.
Note: Successful operation of the power management hand-shaking signals requires coordination
between the BCM4330 firmware and the host software (see Figure 8 on page 46).
®
BROADCOM
BCM4330 Preliminary Data Sheet
April 28, 2011 • 4330-DS304-RI
Page 45
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