6

4318C–ULC–08/05

ATU18

PLL Description

ATMEL PLL is available for a large range of frequencies. It has an internal filter and no external

component is necessary.

Programming at customization level allows to choose between four ranges of VCO frequency as

shown in the table below:

Different outputs are also available, to ensure a wide variety of use. The drawing below shows

the IOs of the PLL.

FreqSelect1

FreqSlect0

VCO Frequency

0

0

66-90Mhz

0

1

90-160Mhz

1

0

155-300Mhz

1

1

280-500Mhz

Table 4. Pin Description

Pin Name

TYPE

I/O

Function

FREQIN

digital

I

Reference input frequency

DIVOUT

digital

I

Feedback input frequency

FREQSELECT(1:0)

digital

I

VCO frequency range select

SC2,SC1

digital

I

internal filter value select

ICP(1:0)

digital

I

Charge pump current select

VccPLL

VssPLL

OUT0

OUT90

OUT180

OUT270

OUTX0

OUTX180

OUT1

OUT2

LCK

FREQIN

DIVOUT

ENPLL

FREQSELECT(1:0)

ICP(1:0)

SYNC

VCOIN

ENVCOIN

SC1

SC2

SR1

SR2