Table III describes the high frequency signal connectors on the
AD6122 customer sample boards.
Table III. Evaluation Board SMA Signal Connector
Description
Connector
I CH
Q CH
MODOP
IFIP
TXOP
LOIPP
Description
I Modulator Input. 250 mV p-p into 50 Ω
termination, dc coupled. The level shifting and
phase splitting is done on board by the AD830
amplifiers.
Q Modulator Input. 250 mV p-p into 50 Ω
termination, ac coupled. The level shifting and
phase splitting is done on board by the AD830
amplifiers.
Modulator Output. The differential-to-single
ended conversion is performed by a balun on
the board. Impedance matched to 50 Ω for
130.38 MHz IF frequency.
IF Amplifier Input. Single-ended-to-differential
conversion performed by a balun on board.
Impedance matched to 50 Ω for 130.38 MHz IF
frequency.
IF Amplifier Output. Differential-to-single-
ended conversion performed by a balun on
board. Impedance matched to 50 Ω for 130.38
MHz IF frequency.
Local oscillator positive input at 2 × IF
frequency.
AD6122
Table IV lists the connections for the 20-pin power-supply
connector.
Table IV. 20-Pin Power Supply Connection Information
Pin #
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Function
VPOS for AD6122; 2.9 V to 4.2 V using regulator; 2.7 V
to 4.2 V bypassing regulator.
VPOS for AD6122; 2.9 V to 4.2 V using regulator; 2.7 V
to 3.6 V bypassing regulator.
Ground.
Ground.
Ground.
Regulated Output or Input Voltage; Connects to Pin 5
on AD6122.
Ground.
Ground.
Ground.
Ground.
Ground.
PD1; Power-Down 1 Input.
Ground.
1.23 V Reference Voltage from AD6122.
Ground.
VGAIN; Gain Control Voltage Input.
–15 V Supply for AD830 Differential Amplifier.
+15 V Supply for AD830 Differential Amplifier.
MODCMREF; common-mode reference output for
baseband converter common-mode reference input.
PD2; Power-Down 2 Input.
A schematic diagram of the evaluation board is on the next two
pages.
REV. B
–17–