ATEVK1105 Atmel, ATEVK1105 Datasheet - Page 57

• Manufacturer Part Number: ATEVK1105
• Description: KIT EVAL FOR AT32UC3A0
• Manufacturer: Atmel
• Series: AVR®32r
• Type: MCUr

Specifications of ATEVK1105

• Contents: Evaluation Board, Software and Documentation
• Processor To Be Evaluated: AT32UC3A0512
• Processor Series: AVR
• Data Bus Width: 32 bit
• Interface Type: USART, TWI, USB, SPI, Ethernet
• Operating Supply Voltage: 3.3 V
• Silicon Manufacturer: Atmel
• Core Architecture: AVR
• Core Sub-architecture: AVR UC3
• Silicon Core Number: AT32UC3A0512
• Silicon Family Name: AVR
• Kit Contents: Board CD Docs
• Rohs Compliant: Yes
• For Use With/related Products: AT32UC3A0
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

O s c 1
c lo c k
O s c 0
13.5.4.1
32058J–AVR32–04/11
c lo c k
P L L O S C
0
1
Enabling the PLL
D iv id e r
P L L D I V
I n p u t
divide the output of the PLL by two and bring the clock in range of the max frequency of the
CPU.
When the PLL is switched on, or when changing the clock source or multiplication factor for the
PLL, the PLL is unlocked and the output frequency is undefined. The PLL clock for the digital
logic is automatically masked when the PLL is unlocked, to prevent connected digital logic from
receiving a too high frequency and thus become unstable.
Figure 13-3. PLL with control logic and filters
PLLn is enabled by writing the PLLEN bit in the PLLn register. PLLOSC selects Oscillator 0 or 1
as clock source. The PLLMUL and PLLDIV bitfields must be written with the multiplication and
division factors, respectively, creating the voltage controlled ocillator frequency f
frequency f
If PLLOPT[1] field is set to 0:
If PLLOPT[1] field is set to 1:
The PLLn:PLLOPT field should be set to proper values according to the PLL operating fre-
quency. The PLLOPT field can also be set to divide the output frequency of the PLLs by 2.
The lock signal for each PLL is available as a LOCKn flag in POSCSR. An interrupt can be gen-
erated on a 0 to 1 transition of these bits.
f
f
f
f
VCO
VCO
PLL
PLL
= f
= f
= (PLLMUL+1)/(PLLDIV) • f
= 2*(PLLMUL+1) • f
PLL
D iv id e r
O u t p u t
D e t e c t o r
P L L M U L
VCO.
VCO
P h a s e
:
/ 2
.
P L L O P T
V C O
OSC
if PLLDIV = 0.
f
OSC
v c o
if PLLDIV > 0.
D e t e c t o r
1 / 2
L o c k
P L L O P T [ 1 ]
0
1
f
P L L
M a s k
AT32UC3A
VCO
L o c k b it
and the PLL
P L L c lo c k
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