BCM43903 Datasheet, PDF (15/87 Pages) Cypress Semiconductor – WICED™ IEEE 802.11 b/g/n SoC with an Embedded Applications Processor

BCM43903 Preliminary Data Sheet
Power Supplies and Power Management
Section 2: Power Supplies and Power
Management
Power Supply Topology
One core buck regulator, multiple LDO regulators, and a power management unit (PMU) are integrated into the
BCM43903. All regulators are programmable via the PMU. These blocks simplify power supply design for
application and WLAN functions in embedded designs.
A single VBAT (3.0V to 4.8V DC maximum) and VIO supply (1.8V to 3.3V) can be used, with all additional
voltages being provided by the regulators in the BCM43903.
The REG_ON control signal is used to power up the regulators and take the appropriate sections out of reset.
The CBUCK, CLDO, LNLDO, and other regulators power up when any of the reset signals are deasserted. All
regulators are powered down only when REG_ON is deasserted. The regulators may be turned off/on based on
the dynamic demands of the digital baseband.
The BCM43903 provides a low power-consumption mode whereby the CBUCK, CLDO, and LNLDO regulators
are shut down. When in this state, the low-power linear regulator (LPLDO1) supplied by the system VIO supply
provides the BCM43903 with all required voltages.
BCM43903 Power Management Unit Features
The BCM43903 supports the following Power Management Unit (PMU) features:
• VBAT to 1.35Vout (550 mA maximum) core buck (CBUCK) switching regulator
• VBAT to 3.3Vout (450 mA maximum) LDO3P3
• 1.35V to 1.2Vout (350 mA maximum) CLDO with bypass mode for deep-sleep
• 1.35V to 1.2Vout (55 mA maximum) LDO for BBPLL
• Additional internal LDOs (not externally accessible)
• PMU internal timer auto-calibration by the crystal clock for precise wake-up timing from the low power-
consumption mode.
Figure 3 and Figure 4 on page 16 show the regulators and a typical power topology.
Broadcom^®
March 12, 2016 • 43903-DS102-R
BROADCOM CONFIDENTIAL
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