adf4351 Analog Devices, Inc., adf4351 Datasheet - Page 7

• Manufacturer Part Number: adf4351
• Description: Wideband Synthesizer With Integrated Vco Preliminary Technical Data Adf4351
• Manufacturer: Analog Devices, Inc.

Preliminary Technical Data
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
Table 4. Pin Function Descriptions
Pin No.
1
2
3
4
5
6
7
8
9
10
11, 18, 21
12
13
14
15
16, 17
19
20
Mnemonic
CLK
DATA
LE
CE
SW
V
CP
CP
AGND
AV
A
RF
RF
RF
RF
V
TEMP
V
P
VCO
TUNE
GNDVCO
OUT
OUT
OUT
OUT
OUT
GND
DD
A+
A−
B+
B−
Description
Serial Clock Input. Data is clocked into the 32-bit shift register on the CLK rising edge. This input is a high
impedance CMOS input.
Serial Data Input. The serial data is loaded MSB first with the three LSBs as the control bits. This input is a high
impedance CMOS input.
Load Enable, CMOS Input. When LE goes high, the data stored in the shift register is loaded into the register
that is selected by the three LSBs.
Chip Enable. A logic low on this pin powers down the device and puts the charge pump into three-state mode.
A logic high on this pin powers up the device depending on the status of the power-down bits.
Fast-Lock Switch. A connection should be made from the loop filter to this pin when using the fast-lock mode.
Charge Pump Power Supply. This pin is to be equal to AV
be placed as close as possible to this pin.
Charge Pump Output. When enabled, this provides ±I
connected to V
Charge Pump Ground. This is the ground return pin for CP
Analog Ground. This is a ground return pin for AV
Analog Power Supply. This pin ranges from 3.0 V to 3.6 V. Decoupling capacitors to the analog ground plane are
to be placed as close as possible to this pin. AV
VCO Analog Ground. These are the ground return pins for the VCO.
VCO Output. The output level is programmable. The VCO fundamental output or a divided down version is available.
Complementary VCO Output. The output level is programmable. The VCO fundamental output or a divided
down version is available.
Auxilliary VCO Output. The output level is programmable. The VCO fundamental output or a divided down
version is available.
Complementary Auxilliary VCO Output. The output level is programmable. The VCO fundamental output or a
divided down version is available.
Power Supply for the VCO. This ranges from 3.0 V to 3.6 V. Decoupling capacitors to the analog ground plane
should be placed as close as possible to these pins. V
Temperature Compensation Output. Decoupling capacitors to the ground plane are to be placed as close as
possible to this pin.
Control Input to the VCO. This voltage determines the output frequency and is derived from filtering the CP
output voltage.
NOTES
1. THE LFCSP HAS AN EXPOSED PADDLE THAT MUST BE CONNECTED TO GND.
TUNE
CP
CP
DATA
CLK
to drive the internal VCO.
OUT
GND
SW
CE
LE
V
P
1
2
3
4
5
6
7
8
Figure 3. Pin Configuration
PIN 1
INDICATOR
Rev. PrC | Page 7 of 28
(Not to Scale)
ADF4351
TOP VIEW
DD
must have the same value as DV
DD
.
VCO
CP
24
23
22
21
20
19
18
17
to the external loop filter. The output of the loop filter is
must have the same value as AV
DD
V
V
R
A
V
TEM P
A
V
OUT
REF
COM
TUNE
SET
GNDVCO
VCO
. Decoupling capacitors to the ground plane are to
GNDVCO
.
DD
.
DD
.
ADF4351
OUT