at91rm3400 ATMEL Corporation, at91rm3400 Datasheet - Page 125

• Manufacturer Part Number: at91rm3400
• Description: Atmel Advanced At91 Arm Microcontroller
• Manufacturer: ATMEL Corporation

Power Management Controller (PMC)
Overview
1790A–ATARM–11/03
The Power Management Controller (PMC) generates all the system clocks thanks to the
integration of two oscillators and two PLLs.
The PMC provides clocks to the embedded processor and enables the idle mode by
stopping the processor clock until the next interrupt.
The PMC independently provides and controls up to thirty peripheral clocks and four
programmable clocks that can be used as outputs on pins to feed external devices. The
integration of the PLLs supplies the USB devices and host ports with a 48 MHz clock, as
required by the bus speed, and the rest of the system with a clock at another frequency.
Thus, the fully-featured Power Management Controller optimizes power consumption of
the whole system and supports the Normal, Idle, Slow Clock and Standby operating
modes.
The main features of the PMC are:
•
•
•
•
Optimizes the Power Consumption of the Whole System
Embeds and Controls
–
–
–
Provides
–
–
–
–
–
–
Four Operating Modes
–
One Main Oscillator and One Slow Clock Oscillator (32.768 kHz)
Two Phase Locked Loops (PLLs) and Dividers
Clock Prescalers
the Processor Clock PCK
the Master Clock MCK
up to two USB Clocks (depending on the USB Ports embedded)
Programmable Automatic PLL Switch-off in USB Device Suspend Conditions
up to Thirty Peripheral Clocks
up to Four Programmable Clock Outputs
Normal Mode, Idle Mode, Slow Clock Mode, Standby Mode
– UHPCK for the USB Host Port
– UDPCK for the USB Device Port
AT91RM3400
125