ADF4116/ADF4117/ADF4118
Rev. D | Page 7 of 28
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
1
2
3
4
5
6
7
8
ADF4116/
ADF4117/
ADF4118
16
15
14
13
12
11
10
9
CP
CPGND
AGND
AV
DD
RF
IN
A
RF
IN
B
FL
O
DV
DD
MUXOUT
LE
CE
REF
IN
DGND
CLK
DATA
V
P
TOP VIEW
(Not to Scale)
00392-003
Figure 3. Pin Configuration
Table 4. Pin Function Descriptions
Pin No. Mnemonic Description
1 FL
O
Fast Lock Switch Output. This can be used to switch an external resistor to change the loop filter bandwidth
and speed up locking the PLL.
2 CP
Charge Pump Output. When enabled, this provides the ± I
CP
to the external loop filter, which in turn drives the
external VCO.
3 CPGND Charge Pump Ground. This is the ground return path for the charge pump.
4 AGND Analog Ground. This is the ground return path for the prescaler.
5 RF
IN
B
Complementary Input to the RF Prescaler. This point should be decoupled to the ground plane with a small
bypass capacitor, typically 100 pF. See
Figure 26.
6 RF
IN
A Input to the RF Prescaler. This small signal input is ac-coupled from the VCO.
7 AV
DD
Analog Power Supply. This can range from 2.7 V to 5.5 V. Decoupling capacitors to the analog ground plane
should be placed as close as possible to this pin. AV
DD
must have the same value as DV
DD
.
8 REF
IN
Reference Input. This is a CMOS input with a nominal threshold of V
DD
/2 and an equivalent input resistance of 100 kΩ.
See
Figure 25. The oscillator input can be driven from a TTL or CMOS crystal oscillator, or it can be ac-coupled.
9 DGND Digital Ground.
10 CE
Chip Enable. A logic low on this pin powers down the device and puts the charge pump output into three-state
mode. Taking the pin high powers up the device depending on the status of the power-down bit F2.
11 CLK
Serial Clock Input. This serial clock is used to clock in the serial data to the registers. The data is latched into the
21-bit shift register on the CLK rising edge. This input is a high impedance CMOS input.
12 DATA
Serial Data Input. The serial data is loaded MSB first with the two LSBs as the control bits. This input is a high
impedance CMOS input.
13 LE
Load Enable, CMOS Input. When LE goes high, the data stored in the shift registers is loaded into one of the four
latches, the latch being selected using the control bits.
14 MUXOUT
This multiplexer output allows either the lock detect, the scaled RF, or the scaled reference frequency to be
accessed externally.
15 DV
DD
Digital Power Supply. This can range from 2.7 V to 5.5 V. Decoupling capacitors to the digital ground plane (1 μF, 1 nF)
should be placed as close as possible to this pin. For best performance, the 1 μF capacitor should be placed within 2 mm
of the pin. The placing of the 1 nF capacitor is less critical, but should still be within 5 mm of the pin.
DV
DD
must have the same value as AV
DD
.
16 V
P
Charge Pump Power Supply. This should be greater than or equal to V
DD
. In systems where V
DD
is 3 V, this supply can
be set to 6 V and used to drive a VCO with a tuning range of up to 6 V.
