ADF4206/ADF4208
Rev. A | Page 7 of 24
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
VDD1
VP1
CPRF1
DGNDRF1
RF1IN
OSCIN
OSCOUT
MUXOUT
VDD2
VP2
CPRF2
DGNDRF2
RF2IN
LE
DATA
CLK
0
103
6-
00
3
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
ADF4206
TOP VIEW
(Not to Scale)
VDD1
CPRF1
DGNDRF1
RF1IN A
OSCIN
OSCOUT
MUXOUT
RF1IN B
AGNDRF1
VDD2
CPRF2
AGNDRF2
LE
DATA
CLK
RF2IN B
RF2IN A
DGNDRF2
01
03
6-
0
04
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
ADF4208
TOP VIEW
(Not to Scale)
VP1
VP2
Figure 3. 16-Lead TSSOP Pin Configuration
Figure 4. 20-Lead TSSOP Pin Configuration
Table 4. Pin Function Descriptions
ADF4206
Pin No.
ADF4208
Pin No.
Mnemonic
Description
1
VDD1
Positive Power Supply for the RF1 Section. A 0.1 μF capacitor is connected between this pin
and DGNDRF1 (the RF1 ground pin). VDD1 should have a value of between 2.7 V and 5.5 V. VDD1
must have the same potential as VDD2.
2
VP1
Power Supply for the RF1 Charge Pump. This is greater than or equal to VDD.
3
CPRF1
Output from the RF1 Charge Pump. This is normally connected to a loop filter that drives the
input to an external VCO.
4
DGNDRF1
Ground Pin for the RF1 Digital Circuitry.
5
RF1IN/RF1INA
Input to the RF1 Prescaler. This low level input signal is taken from the RF1 VCO.
6
8
OSCIN
Oscillator Input. It has a VDD/2 threshold and is driven from an external CMOS or TTL logic gate.
7
9
OSCOUT
Oscillator Output.
8
10
MUXOUT
This multiplexer output allows the IF/RF lock detect, the scaled RF, or the scaled reference
9
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 22-bit shift register on the CLK rising edge. This input is a high impedance
CMOS input.
10
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.
11
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.
12
16
RF2IN/RF2INA
Input to the RF2 Prescaler. This low level input signal is normally ac-coupled to the external
VCO.
13
17
DGNDRF2
Ground Pin for the RF2, Digital, Interface, and Control Circuitry.
14
18
CPRF2
Output from the RF2 Charge Pump. This is normally connected to a loop filter that drives the
input to an external VCO.
15
19
VP2
Power Supply for the RF2 Charge Pump. This is greater than or equal to VDD.
16
20
VDD2
Positive Power Supply for the RF2, Interface, and Oscillator Sections. A 0.1 μF capacitor is
connected between this pin and DGNDRF2 (the RF2 ground pin). VDD2 has a value between 2.7 V
and 5.5 V. VDD2 must have the same potential as VDD1.
N/A
6
RF1INB
Complementary Input to the RF1 Prescaler of the ADF4208. This point is decoupled to the
ground plane with a small bypass capacitor.
N/A
7
AGNDRF1
Ground Pin for the RF1 Analog Circuitry.
N/A
14
AGNDRF2
Ground Pin for the RF2 Analog Circuitry.
N/A
15
RF2INB
Complementary Input to the RF2 Prescaler. This point is decoupled to the ground plane with a
small bypass capacitor.