AT91SAM7S256D-AU Atmel, AT91SAM7S256D-AU Datasheet - Page 29

• Manufacturer Part Number: AT91SAM7S256D-AU
• Description: ARM Microcontrollers - MCU 256K Flash SRAM 64K ARM based MCU
• Manufacturer: Atmel
• Series: SAM7S256r

Specifications of AT91SAM7S256D-AU

• Rohs: yes
• Core: ARM
• Processor Series: AT91SAM
• Data Bus Width: 16 bit/32 bit
• Maximum Clock Frequency: 55 MHz
• Program Memory Size: 256 KB
• Data Ram Size: 64 KB
• On-chip Adc: Yes
• Operating Supply Voltage: 3 V to 3.6 V
• Operating Temperature Range: - 40 C to + 85 C
• Package / Case: LQFP-64
• Mounting Style: SMD/SMT
• Interface Type: 2-Wire, I2S, SPI, USART
• Length: 7 mm

9.2
9.3
Clock Generator
The Clock Generator embeds one low-power RC Oscillator, one Main Oscillator and one PLL with the following
characteristics:
It provides SLCK, MAINCK and PLLCK.
Figure 9-3. Clock Generator Block Diagram
Power Management Controller
The Power Management Controller uses the Clock Generator outputs to provide:
The Master Clock (MCK) is programmable from a few hundred Hz to the maximum operating frequency of the device.
The Processor Clock (PCK) switches off when entering processor idle mode, thus allowing reduced power consumption
while waiting for an interrupt.
RC Oscillator ranges between 22 kHz and 42 kHz
Main Oscillator frequency ranges between 3 and 20 MHz
Main Oscillator can be bypassed
PLL output ranges between 80 and 220 MHz
the Processor Clock PCK
the Master Clock MCK
the USB Clock UDPCK (not present on SAM7S32/16)
all the peripheral clocks, independently controllable
three programmable clock outputs
PLLRC
XOUT
XIN
Clock Generator
Management
Embedded
Status
Oscillator
Oscillator
PLL and
Controller
Divider
Main
Power
RC
Control
Slow Clock
SLCK
Main Clock
MAINCK
PLL Clock
PLLCK
SAM7S Series [DATASHEET]
6175M–ATARM–26-Oct-12
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