MAXIM MAX2371, MAX2373 Technical data

General Description

The MAX2371/MAX2373 wideband low-noise amplifier
(LNA) ICs are designed for direct conversion receiver
(DCR) or very low intermediate frequency (VLIF) receiver
applications. They contain single-channel, single-ended
LNAs with switchable attenuator and automatic gain con­trol (AGC) intended as a low-noise gain stage. These
devices provide high gain-control range (typically 60dB)
at radio frequency (RF) with excellent noise and reverse
isolation characteristics.

The MAX2371/MAX2373 can work over the frequency
range from 100MHz to 1GHz. In practice, only a narrow
band is needed in each application, so different matching
circuits can be applied. The devices are dynamically con­figured through the digital/analog control pins to select
either maximum gain and low noise figure or power-saving
mode. In addition, the MAX2371/MAX2373 feature
high/low-current modes, high/low attenuation modes, lin­early controlled gain states, and shutdown mode.

Applications

Direct Conversion Receiver (DCR)

Very Low IF Receiver

Features

♦ Low Noise Figure (1.8dB typical)

♦ High Small-Signal Gain (15dB Nominal)

♦ Wide Frequency Range of Operation

(100MHz to 1GHz)

♦ 20dB Step Attenuator

♦ 45dB AGC Range Excluding Step Attenuator

♦ 2.65V to 3.3V Single-Supply Operation

♦ Shutdown Mode

♦ 3.5mA Supply Current, Adjustable Down to 2.5mA

♦ 40dB Reverse Isolation

MAX2371/MAX2373

LNAs with Step Attenuator and VGA

________________________________________________________________ Maxim Integrated Products 1

Ordering Information

19-2301; Rev 1; 10/06

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.

EVALUATION KIT

AVAILABLE

PART

TEMP RANGE

PIN­PACKAGE

PKG

CODE

MAX2371EGC

12 QFN-EP*

G1233-1

MAX2371ETC

T1233-3

MAX2371ETC+

T1233+3

MAX2373EGC

12 QFN-EP*

G1233-1

MAX2373ETC

T1233-3

MAX2373ETC+

T1233+3

TOP VIEW

12

GND11RF_V

CC

10

RSET

45

AGC6LNA_I

1

2LNA_E

3

9

8

7RX_EN

AGC_BYP

LNA_V

CC

LNA_OUT

MAX2371
MAX2373

LNA_IN

RF_ATTN

QFN/TQFN

Pin Configuration

AGC

RF_V

CC

GND

LNA_OUT

LNA_IN

AGC_BYP

EXPONENTIAL

CONVERTER

AGC
AMP

LNA

RF_ATTN

RF

ATTENUATOR

LNA_V

CC

LNA_I

RX_EN

LNA_E

RSET

MAX2371
MAX2373

Functional Diagram

*EP = Exposed pad.
+Denotes lead-free package.

-40°C to +85°C

-40°C to +85°C 12 TQFN-EP*

-40°C to +85°C 12 TQFN-EP*

-40°C to +85°C

-40°C to +85°C 12 TQFN-EP*

-40°C to +85°C 12 TQFN-EP*

MAX2371/MAX2373

LNAs with Step Attenuator and VGA

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

DC ELECTRICAL CHARACTERISTICS

(VCC= 2.775V, RX_EN = high, R

SET

= 1.1kΩ, V

AGC

= VCC/2, TA= -40°C to +85°C. Typical values are at TA= +25°C, unless other-

wise noted.)

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.

VCCto GND...........................................................-0.3V to +3.6V

All Pins Excluding Grounds to Pin GND.....-0.3V to (V

CC

+ 0.3V)

LNA Input Power (RX_EN = low) ........................................5dBm

Continuous Power Dissipation (T

A

= +70°C)

12-Pin QFN (derate 11.9mW/°C above +70°C) ...........952mW

Operating Temperature Range ...........................-40°C to +85°C

Junction Temperature......................................................+150°C

Storage Temperature Range .............................-65°C to +160°C

Soldering Temperature (10s) ...........................................+300°C

PARAMETER

CONDITIONS

UNITS

Supply Voltage V

CC

V

RX_EN = low, VCC = 3.3V 0.5 20 µA

LNA_I = high, RF_ATTN = low 3.5 5.5 mASupply Current I

CC

LNA_I = low 2.5 3.5 mA

Digital Input Logic High V

IH

Pins LNA_I, RF_ATTN, RX_EN 0.7 ✕ V

CC

V

Digital Input Logic Low V

IL

Pins LNA_I, RF_ATTN, RX_EN 0

V

Logic Pin Impedance Logic pins RX_EN, RF_ATTN, LNA_I 50 kΩ

AGC Pin Impedance Pins AGC

kΩ

AC ELECTRICAL CHARACTERISTICS

(MAX2371/MAX2373 EV Kits, VCC= 2.65V to 3.3V, RX_EN = high, R

SET

= 1.1kΩ, TA= -40°C to +85°C. Typical values are at VCC=

2.775V; for MAX2371 f

RF

= 150MHz, for MAX2373 fRF= 850MHz to 940MHz; TA= +25°C, unless otherwise noted.) (Note 1)

PARAMETER CONDITIONS

UNITS

LNA AND AGC AMP CHARACTERISTICS

Low band (MAX2371)

Radio Frequency Range (Note 2)

High band (MAX2373)

MHz

MAX2371 -12

LNA_I = high;
RF_ATTN = low

MAX2373 -15

MAX2371 -14 -10

Input Return Loss (S11)
(Note 3)

LNA_I = high;
RF_ATTN = high

MAX2373 -10

dB

MAX2371 -40 -35

Reverse Isolation (S12) Over AGC range

MAX2373 -42 -35

dB

MAX2371 13

16

LNA_I = high, TA =
+25°C, V

CC

= 2.775V

MAX2373 14

17

MAX2371

12

Max Power Gain (Note 3)

LNA_I = low, T

A

=

+25°C, V

CC

= 2.775V

MAX2373

13

dB

Gain Variation Over Temperature TA = -40°C to +85°C, V

AGC

< 1.8V

2.0 dB

SYMBOL

MIN TYP MAX

2.65 2.775 3.30

0.3 ✕ V

100

MIN TYP MAX

136 150 174

850 900 940

14.5

15.5

10.5

10.5

-2.0

V

CC

CC

-9.5

-9.5

-6.5

MAX2371/MAX2373

LNAs with Step Attenuator and VGA

_______________________________________________________________________________________ 3

AC ELECTRICAL CHARACTERISTICS (continued)

(MAX2371/MAX2373 EV Kits, VCC= 2.65V to 3.3V, RX_EN = high, R

SET

= 1.1kΩ, TA= -40°C to +85°C. Typical values are at VCC=

2.775V; for MAX2371 f

RF

= 150MHz, for MAX2373 fRF= 850MHz to 940MHz; TA= +25°C, unless otherwise noted.) (Note 1)

PARAMETER CONDITIONS

UNITS

V

AGC

= 1.275V 1.8 2.2

V

AGC

= 1.575V 5.0 7.7

V

AGC

= 1.875V 11

LNA_I = high, TA =
+25°C, V

CC

= 2.775V,

RF_ATTN = low

V

AGC

= 2.175V 20

SSB Noise Figure vs. AGC

LNA_I = low, T

A

=

+25°C, V

CC

= 2.775V,

RF_ATTN = low

V

AGC

= 1.275V 2.1 2.6

dB

LNA_I = high

RF_ATTN = low,
V

AGC

< 1.8V

LNA_I = low -24 -22

LNA_I = high -3 0

Input 1dB Compression Point

RF_ATTN = high,
V

AGC

< 1.8V

LNA_I = low -9

dBm

LNA_I = high -5 -1

-7 -4

RF_ATTN = low,
V

AGC

= VCC/2

-12 -9

dBm

Input IP3 (Notes 4, 5)

RF_ATTN = high,

LNA_I = high 9 13

dBm

MAX2371

-8

Input IP3 Over AGC Range

RF_ATTN = low, LNA_I = high,
V

AGC

= V

CC

/2 to 1.80V

MAX2373

dBm

AGC RESPONSE

AGC Attenuation Range (Note 6)

V

CC

= 2.775V, RF_ATTN = low, V

AGC

= 1.3375V

to 2.575V, T

A

= +25°C

35 45 dB

RF_ATTN = low, V

AGC

= 1.625V 32 40 47

AGC Slope Over Control Range

RF_ATTN = high, V

AGC

= 1.625V 24 33 41

dB/V

RF STEP ATTENUATOR

MAX2371

Gain Step

RF_ATTN = high to low,
LNA_I = high

MAX2373

dB

Note 1: Parameters over temperature and supply voltage range are guaranteed by design and characterization, unless otherwise noted.
Note 2: Operation outside these frequency bands is possible but has not been characterized. See Typical Operating Characteristics.
Note 3: Measured with external matching network.
Note 4: f

IN1

= 150MHz, f

IN2

= 150.1MHz, PIN= -30dBm for both tones (MAX2371).

Note 5: f

IN1

= 900MHz, f

IN2

= 900.1MHz, PIN= -30dBm for both tones (MAX2373).

Note 6: Parameters are guaranteed by production test.

V

AGC

= V

/2 to 2.575V

CC

LNA_I = low

MIN TYP MAX

14.5

-21.5 19.5

-6.5

MAX2371

MAX2373

-10.5

-12.5 -10.5

16.0 17.5 19.0

18.0 19.5 21.0