MAX2374 Evaluation Kit

2

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Quick Start

The MAX2374 EV kit is fully assembled and factory test-

ed. Follow the instructions in the Connections and Setup

section for proper device evaluation.

Test Equipment Required

This section lists the recommended test equipment to

verify operation of the MAX2374. It is intended as a guide

only, and some substitutions are possible:

•

One RF signal generator capable of delivering at

least 0dBm of output power up to 1.0GHz (HP 8648C

or equivalent)

•

An RF spectrum analyzer that covers the MAX2374’s

operating frequency range as well as a few harmon-

ics (HP 8561E, for example)

•

A power supply capable of delivering +2.7V to +5.5V

•

Two 50

Ω SMA cables

•

(Optional) An ammeter for measuring the supply cur-

rent

•

(Optional) A noise figure meter (HP 8970B, for exam-

ple)

•

(Optional) A network analyzer (HP 8753D, for exam-

ple) to measure return loss and gain

Connections and Setup

Checking Power Gain

This section provides a step-by-step guide to operating

the EV kit and exercising its function:

1) Connect a DC supply set to +2.75V (through an

minals.

2) Set the generator for an output frequency of 880MHz

at a power level of -30dBm. Connect the signal gen-

erator to the RF IN SMA connector.

3) Connect a spectrum analyzer to the EV kit’s RF OUT

SMA connector. Set it to a center frequency of

880MHz, a total span of 30MHz, and a reference

level of -10dBm.

4) Verify that JU1 is set to HI and JU2 is set to R2.

Jumper JU2 alters the linearity of the MAX2374.

Connect JU2 to R1 to increase linearity and supply

current. Connect to R3 to decrease linearity and sup-

ply current. JU2 also places the MAX2374 in shut-

down mode. Connect JU2 to GND or leave open to

enable shutdown.

5) Turn on the DC supply. The supply current should

read approximately 8.5mA (if using an ammeter).

6) Activate the RF generator’s output. A signal on the

spectrum analyzer’s display should indicate a typical

power of -15dB after accounting for cable and board

losses.

7) Move JU1 to GND (LO) to reduce the gain to about

1dB. The spectrum analyzer should indicate a typical

power of -29dBm after accounting for cable and

board losses.

8) (Optional) Another method for determining gain is by

using a network analyzer. This has the advantage of

displaying gain vs. frequency, in addition to display-

ing input and output return loss. Refer to the network

analyzer manufacturer’s user manual for setup

details.

Checking Noise Figure

Noise figure measurements on low-noise devices such

as the MAX2374 are extremely sensitive to lab setup and

board losses and parasitics. There are many techniques

and precautions for measuring a low noise-figure device.

Detailed explanation of these items goes beyond the

scope of this document. For more information on how to

perform this level of noise figure measurement, refer to

the noise figure meter operating manual as well as to

Hewlett Packard application note #57-2, Noise Figure

Measurement Accuracy.

Layout Considerations

Design the layout for the IC as compact as possible to

minimize the parasitics. The chip-scale IC package uses

a bump pitch of 0.5mm (19.7mil) and a bump diameter of

0.3mm (~13mil). Therefore, lay out the solder pad spac-

ing on 0.5mm (19.7mil) centers, and use a pad size of

0.25mm (~10mil) and a solder mask opening of 0.33mm

(~13mil). Round or square pads are permissible.

Connect multiple vias from the ground plane as close as

possible to the ground pins.

Install capacitors as close as possible to the IC supply

voltage pin and supply end of the series inductor. Place

the ground end of these capacitors near the IC GND pins

to provide a low-impedance return path for the signal

current.

Modifying the EV Kit

The MAX2374 EV kit is factory-configured for operation at

880MHz and is easily configured to operate from

750MHz to 1000MHz. Use the device’s parameters listed

in Table 1 of the MAX2374 data sheet to determine the

proper input and output matching components at other

frequencies.

The MAX2374 is designed for AC-coupled operation.

When determining matching components for other fre-

quencies, ensure that a DC-blocking capacitor is part of

the matching network.

Figure 1 shows the MAX2374 EV kit schematic.