datasheetbank_Logo
Integrated circuits, Transistor, Semiconductors Search and Datasheet PDF Download Site

ADF4107BRUZ-REEL7 View Datasheet(PDF) - Analog Devices

Part Name
Description
View to exact match
ADF4107BRUZ-REEL7
ADI
Analog Devices ADI
ADF4107BRUZ-REEL7 Datasheet PDF : 20 Pages
First Prev 11 12 13 14 15 16 17 18 19 20
Data Sheet
Charge Pump Currents
CPI3, CPI2, and CPI1 program Current Setting 1 for the charge
pump. CPI6, CPI5, and CPI4 program Current Setting 2 for the
charge pump. The truth table is given in Figure 25.
Prescaler Value
P2 and P1 in the function latch set the prescaler values. The
prescaler value should be chosen so that the prescaler output
frequency is always less than or equal to 300 MHz. Thus, with
an RF frequency of 4 GHz, a prescaler value of 16/17 is valid but
a value of 8/9 is not valid.
PD Polarity
This bit sets the phase detector polarity bit. See Figure 25.
CP Three-State
This bit controls the CP output pin. With the bit set high, the
CP output is put into three-state. With the bit set low, the CP
output is enabled.
INITIALIZATION LATCH
The initialization latch is programmed when C2 and C1 are set
to 1 and 1. This is essentially the same as the function latch
(programmed when C2, C1 = 1, 0).
However, when the initialization latch is programmed an
additional internal reset pulse is applied to the R and AB
counters. This pulse ensures that the AB counter is at load point
when the AB counter data is latched and the device will begin
counting in close phase alignment.
If the latch is programmed for synchronous power-down (CE
pin is high; PD1 bit is high; PD2 bit is low), the internal pulse
also triggers this power-down. The prescaler reference and the
oscillator input buffer are unaffected by the internal reset pulse and
so close phase alignment is maintained when counting resumes.
When the first AB counter data is latched after initialization, the
internal reset pulse is again activated. However, successive AB
counter loads after this will not trigger the internal reset pulse.
DEVICE PROGRAMMING AFTER INITIAL POWER-UP
After initially powering up the device, there are three ways to
program the device.
Initialization Latch Method
1. Apply VDD.
2. Program the initialization latch (11 in two LSBs of input
word). Make sure that the F1 bit is programmed to 0.
3. Next, do a function latch load (10 in two LSBs of the
control word), making sure that the F1 bit is programmed
to a 0.
4. Then do an R load (00 in two LSBs).
ADF4107
5. Then do an AB load (01 in two LSBs).
6. When the initialization latch is loaded, the following
occurs:
a. The function latch contents are loaded.
b. An internal pulse resets the R, AB, and timeout counters to
load-state conditions and also three-states the charge
pump. Note that the prescaler band gap reference and the
oscillator input buffer are unaffected by the internal reset
pulse, allowing close phase alignment when counting
resumes.
c. Latching the first AB counter data after the initialization
word activates the same internal reset pulse. Successive AB
loads do not trigger the internal reset pulse unless there is
another initialization.
CE Pin Method
1. Apply VDD.
2. Bring CE low to put the device into power-down. This is
an asychronous power-down in that it happens immediately.
3. Program the function latch (10).
4. Program the R counter latch (00).
5. Program the AB counter latch (01).
6. Bring CE high to take the device out of power-down. The
R and AB counters resume counting in close alignment.
Note that after CE goes high, a duration of 1 µs may be required
for the prescaler band gap voltage and oscillator input buffer
bias to reach steady state.
CE can be used to power the device up and down in order to
check for channel activity. The input register does not need to
be reprogrammed each time the device is disabled and enabled
as long as it has been programmed at least once after VDD was
initially applied.
Counter Reset Method
1. Apply VDD.
2. Do a function latch load (10 in two LSBs). As part of this,
load 1 to the F1 bit. This enables the counter reset.
3. Do an R counter load (00 in two LSBs).
4. Do an AB counter load (01 in two LSBs).
5. Do a function latch load (10 in two LSBs). As part of this,
load 0 to the F1 bit. This disables the counter reset.
This sequence provides the same close alignment as the
initialization method. It offers direct control over the internal
reset. Note that counter reset holds the counters at load point
and three-states the charge pump, but does not trigger
synchronous power-down.
Rev. D | Page 17 of 20
 

Share Link: 

datasheetbank.com [ Privacy Policy ] [ Request Datasheet ] [ Contact Us ]