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FUNCTIONAL DESCRIPTION

Clock Inputs (CLK_IN0 and CLK_IN1)

CDCE706

SCAS815A – OCTOBER 2005 – REVISED OCTOBER 2005

SSC2

SSC1

SSC0

Function

1

0

1

SSC Modulation Amount 1.5% (down spread)

1

1

0

SSC Modulation Amount 2% (down spread)

1

1

1

SSC Modulation Amount 3% (down spread)

Byte 25, Bit [7]: Permanently Lock EEPROM-Data

EELOCK

0

No

Yes

1

Yes

(1)

If this bit is set, the actual data in the EEPROM will be permanently locked. There is no further programming possible, even this bit is set

low. Data, however can still be written via SMBUS to the internal register to change device function on the fly. But new data no longer

can be stored into the EEPROM.

(2)

Unless customer specific setting.

BC6

BC5

BC4

BC3

BC2

BC1

BC0

No. of Bytes

0

0

0

0

0

0

0

Not allowed

0

0

0

0

0

0

1

1

0

0

0

0

0

1

0

2

0

0

0

0

0

1

1

3

•

•

•

0

0

1

1

0

1

1

27

Yes

•

•

•

1

1

1

1

1

0

1

125

1

1

1

1

1

1

0

126

1

1

1

1

1

1

1

127

(1)

Defines the number of Bytes, which will be sent from this device at the next Block Read protocol.

(2)

Unless customer specific setting.

EEWRITE

Starts EEPROM Write Cycle

0

No

Yes

1

Yes

(1)

The EEPROM WRITE cycle is initiated with the rising edge of the EEWRITE-Bit. A static level high does not trigger an EEPROM WRITE

cycle. This bit stays high until the user reset it to low (it will not automatically be reset after the programming has been completed).

Therefore, to initiate an EEPROM WRITE cycle, it is recommended to send a zero-one sequence to the EEWRITE bit in Byte 26.

During EEPROM programming, no data are allowed to be sent to the device via the SMBus until the programming sequence has been

completed. Data, however, can be readout during the programming sequence (Byte Read or Block Read). The programming status can

be monitored by readout EEPIP, Byte 24–Bit 7. If EELOCK is set, no EEPROM programming will be possible.

(2)

Unless customer specific setting.

The CDCE706 features two clock inputs which can be used as:

•

Crystal oscillator input (default setting)

•

Two independent single-ended LVCMOS inputs

•

Differential signal input

The dedicated clock input can be selected by the input signal source Bit [7:6] of Byte 11.

18