AD8352

Rev. 0| Page 16 of 20

EVALUATION BOARD

An evaluation board is available for experimentation of various parameters such as gain, common-mode level, and distortion. The output

network can be configured for different loads via minor output component changes. The schematic and evaluation board artwork are

presented in Figure 36, Figure 37, and Figure 38. All discrete capacitors and resistors are Size 0402, except for C1 (3528-B).

Table 10. Evaluation Board Circuit Components and Functions

Component

Name

Function

Additional

Information

Pin 8 and Pin 13

VCC

Supply VCC = +5 V.

Pin 6, Pin 7,

Pin 9, Pin 12

GND

Connect to Low Impedance GND.

Pin 14, C9

VCM, Capacitor

Common-Mode Offset Pin. Allows for monitoring or adjustment of the

output common-mode voltage. C9 is a bypass capacitor.

C9 = 0.1 μF

Distortion

Tuning

Components

Distortion Adjustment Components. Allows for third-order distortion

adjustment HD3.

Typically, both are open

above 300 MHz

(microwave) Multilayer

Chip 402 capacitor

Pin 15, C8

ENB, Capacitor

Enable. Apply positive voltage (1.3 V < ENB < VCC) to activate device. Pull

down to disable. Can be bypassed and float high (1.8 V) for on state. C8 is

a bypass capacitor.

Floats to 1.8 V to

maintain device in

power-up mode

C8 = 0.1 μF

R1, R2, R3, R4,

R5, R6, T2, C2,

C3

Resistors,

Transformer,

Capacitors

Input Interface. R1 and R4 ground one side of the differential drive

interface for single-ended applications. T2 is a 1-to-1 impedance ratio

balun to transform a single-ended input into a balanced differential

signal. R2 and R3 provide a differential 50 Ω input termination. R5 and R6

can be increased to reduce gain peaking when driving from a high source

impedance. The 50 Ω termination provides an insertion loss of 6 dB. C2

and C3 provide ac-coupling.

T2 = Macom

™ ETC1-1-13

R1 = open, R2 = 25 Ω,

R3 = 25 Ω, R4 = 0 Ω,

R5 = 0 Ω, R6 = 0 Ω,

C2 = 0.1 μF, C3 = 0.1 μF

R7, R8, R9, R11,

R12, R13, R14,

T1, C4, C5

Resistors,

Transformer,

Capacitors

Output Interface. R13 and R14 ground one side of the differential output

interface for single-ended applications. T1 is a 1-to-1 impedance ratio

balun to transform a balanced differential signal to a single-ended signal.

R8, R9, and R12 are provided for generic placement of matching

components. R7 and R11 allow additional output series resistance when

driving capacitive loads. The evaluation board is configured to provide a

150 Ω to 50 Ω impedance transformation with an insertion loss of 11.6 dB.

C4 and C5 provide ac-coupling. R7 and R11 provide additional series

resistance when driving capacitive loads.

T1= Macom ETC1-1-13

R7 = 0 Ω, R8 = 86.6 Ω,

R9 = 57.6 Ω,

R11 = 0 Ω, R12 = 86.6 Ω,

R13 = 0 Ω, R14 = open

C4 = 0.1 μF, C5 = 0.1 μF

Resistor

Refer to Table 6 and Table 7 when selecting the gain resistor.

for a gain of 10 dB

C1, C6, C7

Capacitors

Power Supply Decoupling. The supply decoupling consists of a 10 μF

capacitor to ground. C6 and C7 are bypass capacitors.

C1 = 10 μF

C6, C7 = 0.1 μF

Pin 14

VCM

Common-Mode Offset Adjustment. Use Pin 14 to trim common-mode

input/output levels. By applying a voltage to Pin 14, the input and output,

common-mode voltage can be directly adjusted.

Typically decoupled to

ground using a 0.1 μF

capacitor with

ac-coupled

input/output ports