General Description
The MAX2027 evaluation kit (EV kit) simplifies the evalu-
ation of the MAX2027 high-linearity, digitally controlled,
variable-gain amplifier. The kit is fully assembled and
tested at the factory. Standard 50SMA connectors
are included for the input and output to allow quick and
easy evaluation on the test bench.
This EV kit provides a list of equipment required to eval-
uate the device, a straightforward test procedure to ver-
ify functionality, a circuit schematic, a bill of materials
(BOM), and artwork for each layer of the PC board.
Contact MaximDirect sales at 888-629-4642 to check
pricing and availability of these kits.
Features
Fully Assembled and Tested
50MHz to 400MHz Frequency Range
Variable Gain: -8dB to +15dB
Output IP3: 35dBm (All Gain Settings)
Noise Figure: 4.7dB at Maximum Gain
Digitally Controlled Gain with 1dB Resolution and
±0.05dB State-to-State Accuracy
Evaluates: MAX2027
MAX2027 Evaluation Kit
________________________________________________________________ Maxim Integrated Products 1
19-2686; Rev 1; 2/04
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Ordering Information
Component Suppliers
DESIGNATION QTY DESCRIPTION
C1, C3, C4 (Note 1) 3 1000pF ±5%, 50V C0G ceramic capacitors (0603)
Murata GRM1885C1H102J
C2, C5 2 100pF ±5%, 50V C0G ceramic capacitors (0603)
Murata GRM1885C1H101J
C6, C7 2 0.1µF ±10%, 16V X7R ceramic capacitors (0603)
Murata GRM188R71C104K
C8, C9 0 Not installed
C10 1 0.047µF ±10%, 25V X7R ceramic capacitor (0603)
Murata GRM188R71E473K
J1, J2 2 PC board edge-mount SMA RF connectors (flat-tab launch)
Johnson 142-0741-856
J3 1 Header 5 × 2 (0.100 spacing for 0.062in thick board)
Molex 10-88-1101 or equivalent
J4 0 Not installed
L1 1 330nH ±5% wire-wound IND (0805)
Coilcraft 0805CS-331XJBC
L2 1 680nH ±5% wire-wound IND (1008)
Coilcraft 1008CS-681XJBC
L3 1 0 resistor (0603) (used as a jumper for unmatched board)
L4 0 Not installed
R1 1 825 ±1% resistor (0603)
R2–R6 5 47k ±5% resistors (0603)
U1 1 MAX2027EUP-T
PART TEMP RANGE IC PACKAGE
MAX2027EVKIT -40°C to +85°C 20 TSSOP-EP*
SUPPLIER PHONE WEBSITE
Coilcraft 847-639-6400 www.coilcraft.com
Johnson 507-833-8822 www.johnsoncomponents.com
Murata 770-436-1300 www.murata.com
*EP = Exposed paddle.
Note 1: If matching is not required, C3 is installed using one pad of L4 and one pad of C3.
Component List (Unmatched)
Evaluates: MAX2027
Quick Start
The MAX2027 EV kit is fully assembled and factory test-
ed. Follow the instructions in the Connections and
Setup section for proper device evaluation. Table 2 lists
the attenuation setting vs. gain-control bits.
Test Equipment Required
DC supply capable of delivering 5.25V and 100mA of
continuous current
HP 8648 (or equivalent) signal source
HP 8561E (or equivalent) spectrum analyzer capable
of covering the MAX2027’s frequency range as well
as a few harmonics
Two digital multimeters (DMMs) to monitor VCC and
ICC, if desired
HP8753D (or equivalent) network analyzer to measure
return loss and gain
Lowpass filters to attenuate harmonic output of signal
sources, if harmonic measurements are desired
Connections and Setup
This section provides a step-by-step guide to testing
the basic functionality of the EV kit. As a general pre-
caution to prevent damaging the outputs by driving
high-VSWR loads, do not turn on DC power or RF
signal generators until all connections are made.
Gain Setting
Connect the header pins for B4–B0 to GND for maxi-
mum gain (15dB, typ). See Table 2 for other gain set-
ting configurations. To set a logic high on B4–B0, leave
the respective header pin unconnected as on-board
resistors pull up the logic to +5V. To control B4–B0
using external logic (voltage limits per data sheet),
ensure that +5V is applied to the chip. Failure to do so
can cause the on-chip ESD diodes to draw significant
current and may damage the part.
Testing the Supply Current
1) Connect 50terminations to RF_IN and RF_OUT.
2) 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.
3) Enable the DC supply; the supply current should
read approximately 60mA.
MAX2027 Evaluation Kit
2_______________________________________________________________________________________
Table 1. Suggested Components for
Matching
FREQUENCY
(MHz)
COMPONENT
VALUE SIZE
L3, L4 11nH 0603
300 C8, C9 6.8pF 0603
L3, L4 8.7nH 0603
400 C8, C9 5pF 0603
Table 2. Attenuation Setting vs. Gain-
Control Bits
ATTENUATION
(dB)
B4
(16dB)
B3*
(8dB)
B2
(4dB)
B1
(2dB)
B0
(1dB)
000000
100001
200010
300011
400100
500101
600110
700111
801000
901001
10 0 1 010
11 0 1 011
12 0 1 100
13 0 1 101
14 0 1 110
15 0 1 111
16 1 X 0 0 0
17 1 X 0 0 1
18 1 X 0 1 0
19 1 X 0 1 1
20 1 X 1 0 0
21 1 X 1 0 1
22 1 X 1 1 0
23 1 X 1 1 1
*Enabling B4 disables B3.
Evaluates: MAX2027
MAX2027 Evaluation Kit
_______________________________________________________________________________________ 3
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.
Evaluates: MAX2027
MAX2027 Evaluation Kit
4_______________________________________________________________________________________
ATTENUATION
LOGIC CONTROL
1
2
3
4
5
6
7
8
9
10
GND
GND
B4
B3
B2
B1
B0
R6 R5 R4 R3 R2
B4
B3
B2
B1
B0
+5V
RF_IN C1
C8*
L3
+5V
C7 C2
AMP
BIAS
+5V
C6C5
C10
L2
C4 RF_OUT
R1
L1
C3
C9*
L4*
GND
GND
ATTNOUT
GND
GND
AMPIN
IBIAS
ISET
20
19
18
17
16
15
14
13
12
11
J3-9
B3
J3-7
B1
J3-5
GND
J3-3 J3-1
J3-10
B4
J3-8
B2
J3-6
B0
J3-4
GND
J3-2
+5V
J3
TOP VIEW OF HEADER
*THESE COMPONENTS ARE LEFT UNINSTALLED FROM THE FACTORY.
SEE TABLE 1 FOR SUGGESTED MATCHING COMPONENTS AT
DIFFERENT OPERATION FREQUENCIES. RF_TEST ALLOWS FOR
INTERSTAGE MEASUREMENTS.
J1
J4
J2
EXPOSED
PADDLE
MAX2027
Figure 1. MAX2027 EV Kit Schematic
Evaluates: MAX2027
MAX2027 Evaluation Kit
_______________________________________________________________________________________ 5
RF_IN
+5V
GND
B0
RF_OUT
CONTROL
INPUTS
B1
B2
B3
B4
POWER SUPPLY
3-OUT, HPIB
(AG E3631A)
RF SIGNAL GENERATOR
(HP 8648D)
BENCH
MULTIMETER HPIB
(HP 34401A)
RF SPECTRUM ANALYZER
(HP 856xE)
MAX2027
U1
Figure 2. Test Setup Diagram
Evaluates: MAX2027
MAX2027 Evaluation Kit
6_______________________________________________________________________________________
FOR THE GENERIC BOARD, C3 IS INSTALLED USING
ONE PAD OF L4 AND ONE PAD OF C3 AS SHOWN.
MULTIPLE VIAS CONNECT EXPOSED
PADDLE TO LAYER 2 GROUND PLANE
Figure 3. MAX2027 EV Kit Component Placement Guide—Component Side
Evaluates: MAX2027
MAX2027 Evaluation Kit
_______________________________________________________________________________________ 7
Figure 6. MAX2027 EV Kit PC Board Layout—Primary
Component Side Figure 7. MAX2027 EV Kit PC Board Layout—GND Layer
(Layer 2)
Figure 4. MAX2027 EV Kit Component Placement Guide—Top
Silkscreen Figure 5. MAX2027 EV Kit Component Placement Guide—
Bottom Silkscreen
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
8_____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
©2004 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
Evaluates: MAX2027
MAX2027 Evaluation Kit
Figure 8. MAX2027 EV Kit PC Board Layout—Route Layer
(Layer 3) Figure 9. MAX2027 EV Kit PC Board Layout—Secondary Side
Figure 10. MAX2027 EV Kit PC Board Layout—Top Soldermask Figure 11. MAX2027 EV Kit PC Board Layout—Bottom
Soldermask