Power Management Unit; Power Management Unit Features - Analog Devices ADuCM355 Hardware Reference Manual

ADuCM355 Hardware Reference Manual

POWER MANAGEMENT UNIT

DVDD
AVDD_DD
FOR DIGITAL DIE OSCILLATOR,
AND OTHER ANALOG CIRCUITS
DVDD_REG
DVDD
DVDD_REG_AD
AVDD
AVDD_REG

POWER MANAGEMENT UNIT FEATURES

The ADuCM355 contains two separate PMUs, one for each die. The PMUs control the different power modes of each
The power management features of the device include the following:

High efficiency buck converters to reduce power on the digital die.

Buck converter for active mode, which requires external flying capacitors, as shown in the Figure 3. The buck converter is
disabled by default. For optimal performance of the analog peripherals, leave the converter disabled.

The dc-to-dc converter shown on the digital die is optional. If disabled, the three capacitors connected to the VDCDC_x pins
are not required and these five pins can be left unconnected.

Customized clock gating for active modes.

Power gating to reduce leakage in sleep modes.

Voltage monitoring.

Flexible sleep modes with smart peripherals.

Deep sleep modes with no retention.
Three power modes are available: active mode, Flexi mode, and hibernate mode. The power mode control for each die is separate.
Active Mode
The Arm Cortex-M3 is executing from flash and SRAM on the digital die. PMG0 PWRMOD, Bits[1:0] = 00. The analog die circuitry is in
active mode. ALLON PWRMOD, Bits[1:0] = 01.
BUCK
CONVERTOR
DVDD
2.8V TO 3.6V POWER SUPPLY
POWER-ON RESET (POR)
PMG_CTL1[0]
1.2V
LDO
DIGITAL
DIE 3V
SUPPLY
1.8V
DIGITAL
LDO
DVDD
2.8V TO 3.6V POWER SUPPLY
FOR ANALOG DIE CRITICAL
SUPPLY FOR ANALOG CIRCUITS
1.8V
ANALOG
LDO
AVDD
Figure 3. Power Supply Architecture Block Diagram
1
DIGITAL
DIE 3V
MAIN DIGITAL DIE 3V
SUPPLY
0 POWER SUPPLY FOR FLASH
AND OTHER DIGITAL BLOCKS
MAIN DIGITAL DIE 1.2V
POWER SUPPLY FOR
CORTEX-M3, SRAM, FLASH
AND OTHER DIGITAL BLOCKS
MAIN ANALOG DIE 1.8V
DIGITAL POWER SUPPLY
FOR AFE DIE DIGITAL LOGIC
REGULATED ANALOG DIE 1.8V
ANALOG POWER SUPPLY FOR
AFE DIE REFERENCES AND
OTHER CRITICAL ANALOG BLOCKS
Rev. B | Page 25 of 312
UG-1262
DIGITAL DIE
AFE DIE
ADuCM355 die.