ADF4110/ADF4111/ADF4112/ADF4113
PIN FUNCTION DESCRIPTIONS
Pin No.
1
Mnemonic
R
SET
Function
Connecting a resistor between this pin and CPGND sets the maximum charge pump output current. The
nominal voltage potential at the R
SET
pin is 0.56 V. The relationship between I
CP
and R
SET
is
I
CP
max
=
23.5
R
SET
2
3
4
5
6
7
8
CP
CPGND
AGND
RF
IN
B
RF
IN
A
AV
DD
REF
IN
9
10
11
12
13
14
15
16
DGND
CE
CLK
DATA
LE
MUXOUT
DV
DD
V
P
So, with
R
SET
= 4.7 kΩ,
I
CPmax
= 5 mA.
Charge Pump Output. When enabled this provides
±I
CP
to the external loop filter, which in turn drives the
external VCO.
Charge Pump Ground. This is the ground return path for the charge pump.
Analog Ground. This is the ground return path of the prescaler.
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 25.
Input to the RF Prescaler. This small signal input is normally ac-coupled from the VCO.
Analog Power Supply. This may 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 be the same value as DV
DD
.
Reference Input. This is a CMOS input with a nominal threshold of V
DD
/2 and an equivalent input resis-
tance of 100 kΩ. See Figure 24. This input can be driven from a TTL or CMOS crystal oscillator or
it can be ac-coupled.
Digital Ground.
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 will power up the device depending on the status of the power-down bit F2.
Serial Clock Input. This serial clock is used to clock in the serial data to the registers. The data is latched into
the 24-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 two LSBs being 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 registers is loaded into one
of the four latches, the latch being selected using the control bits.
This multiplexer output allows either the Lock Detect, the scaled RF or the scaled Reference Frequency
to be accessed externally.
Digital Power Supply. This may range from 2.7 V to 5.5 V. Decoupling capacitors to the digital ground
plane should be placed as close as possible to this pin. DV
DD
must be the same value as AV
DD
.
Charge Pump Power Supply. This should be greater than or equal to V
DD
. In systems where V
DD
is 3 V,
it can be set to 6 V and used to drive a VCO with a tuning range of up to 6 V.
PIN CONFIGURATIONS
TSSOP
R
SET 1
CP
2
CPGND
3
AGND
4
RF
IN
B
5
16
V
P
CHIP SCALE PACKAGE
17 DV
DD
DGND 9
19 R
SET
16 DV
DD
15 MUXOUT
14 LE
13 DATA
12 CLK
11 CE
20 CP
ADF4110
ADF4111
ADF4112
ADF4113
15
DV
DD
14
MUXOUT
13
LE
CPGND
AGND
AGND
RF
IN
B
RF
IN
A
1
2
3
4
5
TOP VIEW
12
DATA
(Not to Scale)
11
CLK
RF
IN
A
6
AV
DD 7
REF
IN 8
10
CE
9
ADF4110
ADF4111
ADF4112
ADF4113
TOP VIEW
(Not to Scale)
REV. 0
–5–
DGND 10
AV
DD
6
AV
DD
7
REF
IN
8
DGND
18 V
P
AD [ ANALOG DEVICES ]
