AT91SAM7S256-AU-001 Atmel, AT91SAM7S256-AU-001 Datasheet - Page 30

• Manufacturer Part Number: AT91SAM7S256-AU-001
• Description: IC ARM7 MCU 32BIT 256K 64LQFP
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91SAM7S256-AU-001

• Package / Case: 64-LQFP
• Voltage - Supply (vcc/vdd): 1.65 V ~ 1.95 V
• Operating Temperature: -40°C ~ 85°C
• Speed: 55MHz
• Number Of I /o: 32
• Core Processor: ARM7
• Program Memory Type: FLASH
• Ram Size: 64K x 8
• Program Memory Size: 256KB (256K x 8)
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Peripherals: Brown-out Detect/Reset, DMA, POR, PWM, WDT
• Connectivity: I²C, SPI, SSC, UART/USART, USB
• Core Size: 16/32-Bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Other names: AT91SAM7S256AU001

9.2
9.3
30
Clock Generator
Power Management Controller
AT91SAM7S Series Summary
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.
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 fre-
quency 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 AT91SAM7S32/16)
• all the peripheral clocks, independently controllable
• three programmable clock outputs
Clock Generator Block Diagram
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
6175FS–ATARM–03-Dec-07