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MAX2027EVKIT

MAX2027 Evaluation Kit

Maxim Integrated 

MAX2027 Evaluation Kit

Testing the Power Gain

1) Connect the RF signal generator to the RF_IN SMA

connector. Do not turn on the generator’s output. Set

the generator to an output frequency of 50MHz, and

set the generator power level to -10dBm.

2) Connect the spectrum analyzer to the RF_OUT SMA

connector. Set the spectrum analyzer to a center

frequency of 50MHz and a total span of 1MHz.

3) With the DC supply disabled, set it to +5.0V (through

a low internal-resistance ammeter if desired) and

connect to the +5V and GND terminals on the EV kit.

If available, set the current limit to 100mA.

4) Connect B4–B0 to GND for 0dB attenuation.

5) Enable the DC supply, and then activate the RF gener-

ator’s output. A 50MHz signal shown on the spectrum

analyzer display should indicate a magnitude of

approximately 5dBm. Be sure to account for external

cable losses.

6) (Optional) Gain can be determined with a network

analyzer. This has the advantage of displaying gain

over a swept frequency band, in addition to display-

ing input and output return loss. Refer to the network

analyzer manufacturer’s user manual for setup

details.

Detailed Description

Figure 1 is the schematic for the EV kit as shipped. This

circuit is internally matched for operation up to 250MHz.

Component pads for external matching components, L3,

L4, C8, and C9, are included to allow modification for

higher frequency operation (see Table 1 for suggested

components for additional frequencies). C1, C3, and C4

are DC-blocking capacitors for the RF_IN, ATTNOUT, and

RF_OUT ports. To reduce the possibility of noise pickup,

C2, C5, C6, and C7 form the VCC decoupling network.

Note the location of each component.

Modifying the MAX2027 EV Kit

The EV kit can be configured for use at any frequency

between 50MHz and 400MHz. See Table 1 for the cor-

rect matching component values for the desired oper-

ating frequency.

Layout Considerations

The MAX2027 evaluation board can be a guide for your

board layout. Pay close attention to thermal design and

close placement of parts to the IC. The MAX2027 pack-

age exposed paddle (EP) conducts heat from the part

and provides a low-impedance electrical connection.

The EP must be attached to the PC board ground plane

with a low thermal and electrical impedance contact.

Ideally, this can be achieved by soldering the backside

package contact directly to a top metal ground plane

on the PC board. Alternatively, the EP can be connect-

ed to a ground plane using an array of plated vias

directly below the EP. The MAX2027 EV kit uses eight

evenly spaced, 0.016in-diameter, plated through holes

to connect EP to the lower ground planes.

Depending on the RF ground-plane spacing, large sur-

face-mount pads in the RF path may need the ground

plane relieved under them to reduce shunt capacitance.

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