adf4196 Analog Devices, Inc., adf4196 Datasheet - Page 20

• Manufacturer Part Number: adf4196
• Description: Low Phase Noise, Fast Settling, 6 Ghz Pll Frequency Synthesizer
• Manufacturer: Analog Devices, Inc.

ADF4196
R5, the power-down register, can be used to power down the PLL
and differential amplifier sections. After power is initially applied,
Register R5 must be programmed to clear the power-down bits.
Then, before the
R1, and R0 registers must be programmed.
Control Bits
Register R5 is selected with C3, C2, and C1 set to 1, 0, 1.
Power-Down Differential Amplifier
When the DB7 and DB6 bits are set to 1, the differential
amplifier is put into power-down. When DB7 and DB6 are set
to 0, normal operation resumes.
Power-Down Charge Pump
Setting Bit DB5 to 1 activates a charge pump power-down, and
the following events occur:
•
•
POWER-DOWN REGISTER (R5) BIT MAP
All active dc current paths are removed, except for the
differential amplifier.
The R and N divider counters are forced to their load state
conditions.
ADF4196
comes out of power-down, the R2,
F5
0
1
DB7
DIFF AMP
F5
F4
0
1
PD
DIFF AMP
POWER-DOWN
DISABLED
ENABLED
DB6
F4
Figure 34. Bit Map for Register R5
DB5
F3
0
1
F3
Rev. B | Page 20 of 28
CHARGE PUMP
POWER-DOWN
DISABLED
ENABLED
DB4
F2
F2
0
1
CHARGE PUMP
3-STATE
NORMAL OPERATION
3-STATE ENABLED
DB3
F1
F1
0
1
•
•
•
•
•
For normal operation, set Bit DB5 to 0, followed by a write to R0.
CP Three-State
When the CP three-state bit is set to 1, the charge pump outputs
enter three-state. Setting the CP three-state bit to 0 enables the
charge pump outputs.
Counter Reset
When the counter reset bit is set to 1, the counters are held in reset.
For normal operation, set this bit to 0, followed by a write to R0.
COUNTER RESET
NORMAL OPERATION
COUNTER RESET
C3 (1)
DB2
The charge pump is powered down with its outputs in
three-state mode.
The digital lock detect circuitry is reset.
The RF
The reference input buffer circuitry is disabled.
The serial interface remains active and capable of loading
and latching data.
CONTROL
C2 (0)
BITS
DB1
IN
input is debiased.
C1 (1)
DB0
Data Sheet