CYW4343X
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Initiates an enable sequence for each resource that is disabled, is being requested, and has all of its dependencies
enabled.
2.5 Power-Off Shutdown
The CYW4343X provides a low-power shutdown feature that allows the device to be turned off while the host, and any other devices
in the system, remain operational. When the CYW4343X is not needed in the system, VDDIO_RF and VDDC are shut down while
VDDIO remains powered. This allows the CYW4343X to be effectively off while keeping the I/O pins powered so that they do not
draw extra current from any other devices connected to the I/O.
During a low-power shutdown state, provided VDDIO remains applied to the CYW4343X, all outputs are tristated, and most input
signals are disabled. Input voltages must remain within the limits defined for normal operation. This is done to prevent current paths
or create loading on any digital signals in the system, and enables the CYW4343X to be fully integrated in an embedded device and
to take full advantage of the lowest power-savings modes.
When the CYW4343X is powered on from this state, it is the same as a normal power-up, and the device does not retain any infor-
mation about its state from before it was powered down.
2.6 Power-Up/Power-Down/Reset Circuits
The CYW4343X has two signals (see Table 2) that enable or disable the Bluetooth and WLAN circuits and the internal regulator
blocks, allowing the host to control power consumption. For timing diagrams of these signals and the required power-up sequences,
see Section 22.: “Power-Up Sequence and Timing,” on page 116.
Table 2. Power-Up/Power-Down/Reset Control Signals
Signal
Description
WL_REG_ON
This signal is used by the PMU (with BT_REG_ON) to power-up the WLAN section. It is also OR-gated with the
BT_REG_ON input to control the internal CYW4343X regulators. When this pin is high, the regulators are enabled and
the WLAN section is out of reset. When this pin is low, the WLAN section is in reset. If BT_REG_ON and WL_REG_ON
are both low, the regulators are disabled. This pin has an internal 200 k pull-down resistor that is enabled by default.
It can be disabled through programming.
BT_REG_ON
This signal is used by the PMU (with WL_REG_ON) to decide whether or not to power down the internal CYW4343X
regulators. If BT_REG_ON and WL_REG_ON are low, the regulators will be disabled. This pin has an internal 200 k
pull-down resistor that is enabled by default. It can be disabled through programming.
2.7 Wireless Charging
The CYW4343X, when paired with a Broadcom BCM5935X wireless power transfer (WPT) front-end device, complies with the fol-
lowing three wireless charging standards:
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Alliance for Wireless Power (A4WP)
Wireless Power Consortium (WPC)
Power Matters Alliance (PMA)
To support the WPC and PMA standards, control-plane signaling is accomplished using in-band signaling between the BCM5935X
WPT front-end device (located in the power receiving entity) and the power transmitting wireless charger.
To support the A4WP standard, energy is transferred from a Power Transmitting Unit (PTU) to a Power Receiving Unit (PRU). The
energy transferred charges the PRU battery. Bidirectional communication between the PTU and PRU is accomplished using Blue-
tooth Low Energy (BLE), where the PTU is a BLE client and the PRU is a BLE server. Using a BLE link, the PRU sends performance
data to the PTU so that it can adapt its power output to meet the needs of the PRU.
The most common use for wireless charging is to charge a mobile device battery.
Figure 11 shows a simple block diagram of a system that supports the A4WP standard.
Document No. 002-14797 Rev. *H
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