LUCW3000CCN AGERE [Agere Systems], LUCW3000CCN Datasheet - Page 14

• Manufacturer Part Number: LUCW3000CCN
• Description: W3000 PLL Dual-Band Frequency Synthesizer
• Manufacturer: AGERE [Agere Systems]

W3000 PLL Dual-Band Frequency Synthesizer
REF Register
Table 15. ERES: External Resistor Setting for Charge Pump Current (Bit 21)
If bit 21 is set to 0, the W3000 uses its internal current source to set the charge pump currents, with the values
shown in Table 12. If bit 21 is set to 1, the charge pump current is set by an external resistor between pin 9
(RES) and V
where
I
I
RREF = Value of external current reference resistor. See Table 3 for appropriate value.
A tight-tolerance R
Table 16. EN1: Synthesizer Enable (Bit 22)
The MAIN register also contains an enable bit, EN2. The W3000 is enabled and powered down with either the
REF or the MAIN register, whichever was programmed more recently. The contents of the MAIN and REF
registers are maintained in powerdown mode, providing supply voltages are maintained.
Table 17. LD: Lock Detect Enable (Bit 23)
14
I
CP
SET
CP
LD (Bit 23)
(Input Pin 11)
ERES
PWRDN
0
1
I
SET
High
High
0
0
1
1
= Nominal charge pump current.
= Current setting as in Table 12.
Low
Low
*
100
V
DDC
DDC
. In this case, the charge pump current is given by the following formula:
Disabled
Disabled
Enabled
Enabled
A
Mode
Use internal charge pump current setting (not tested in production)
REF
(continued)
Use external resistor to set charge pump current (recommended)
*
. 1
R
EN1
05
REF
0
1
0
1
resistor is recommended.
PLL Condition
Powerdown
Powerdown
Powerdown
Unlocked
Unlocked
Enable
Locked
Locked
Mode
External Resistor Status
Output Level on Pin 8 LockDet
High
High
High
Low
Advance Data Sheet
Lucent Technologies Inc.
December 1999