MAX2240 Evaluation Kit

2

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Quick Start

The MAX2240 EV kit is fully assembled and factory

tested. 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 MAX2240. It is intended as a

guide only, and some substitutions are possible:

•

One RF signal generator capable of delivering at

least +5dBm of output power at the operating fre-

quency (HP 8648D, or equivalent)

•

One RF power sensor capable of handling at least

+20dBm of output power at the operating frequency

(HP 8482A, or equivalent)

•

One RF power meter capable of measuring up to

+20dBm of output power at the operating frequency

(HP 438A, or equivalent)

•

An RF spectrum analyzer that covers the MAX2240

operating frequency range, as well as a few har-

monics (HP 8562E, for example)

•

A power supply capable of up to 0.25A at +2.7V to

+5V

•

An optional ammeter for measuring the supply cur-

rent

•

Two 50

Ω SMA cables

•

One SMA 20dB pad

•

A network analyzer (HP 8753D, for example) to

measure small-signal return loss and gain (optional)

Connections and Setup

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

the EV kit and testing the device’s function. Do not turn

on the DC power or RF signal generators until all

connections are made:

1) Connect a DC supply set to +3.2V (through an

ammeter if desired) to the VCC and GND terminals

on the EV kit. Do not turn on the supply.

2) Connect one RF signal generator to the RFIN SMA

connector; do not turn on the generator’s output.

Set the generator for an output frequency of

2.45GHz at a power level of +3dBm.

3) Connect a 20dB pad to the RFOUT SMA connector

on the EV kit. This is to prevent overloading of the

power sensor and the power meter.

4) Connect a power sensor to the 20dB pad.

5) Connect the power sensor to a power meter. Set

the power meter offset to 20dB and frequency to

2.45GHz.

6) Connect jumpers J1, J2, and J3 to short D0 and D1

to VCC. This sets the MAX2240 to its highest power

mode. The MAX2240 EV kit is shipped in this set-

ting.

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

read approximately 70mA.

8) Activate the RF generator’s output. The power

meter should read approximately +20dBm. The

supply current should increase to approximately

105mA.

9) Another method for determining gain is by using a

network analyzer (optional). This has the advantage

of displaying gain versus a swept-frequency band,

in addition to displaying input return loss. Refer to

the network analyzer manufacturer’s user manual

for setup details.

10) The additional MAX2240 power modes are set by

the jumper settings of J2 (D0) and J3 (D1). See

Table 1 in the MAX2240 data sheet for these power-

level settings.

Layout Issues

A good PC board is an essential part of an RF circuit

design. The EV kit PC board can serve as a guide for

laying out a board using the MAX2240. Keep traces

carrying RF signals as short as possible to minimize

radiation and insertion loss due to the PC board. Each

VCC node on the PC board should have its own decou-

pling capacitor. This minimizes supply coupling from

one section of the IC to another. A star topology for the

supply layout, in which each VCC node on the circuit

has a separate connection to a central VCC node, can

further minimize coupling between sections of the IC.

See the Layout section of the MAX2240 data sheet for

more information.