Datasheet RF2371, RF2371PCBA Datasheet (RF Micro Devices)

Preliminary

R

E

RF2371

4

Typical Applications

•GSMHandsets

• CDMA Handsets

• TDMA Handsets

Product Description

The RF2371 is a general purpose, low-cost, high perfor­mance low noise amplifier designed for operation from a

2.7V to 4V supply with low current consumption. The
attenuation of the device is controlled when in power
down mode, providing a known gain step. The RF2371 is
available in a small industry-standard SOT23-8 surface
mount package, enabling compact designs which con­serve board space. The design featuresa highly accurate
PTAT (Proportional To Absolute Temperature) biasing
scheme using bandgap cells.

3V LOW NOISE AMPLIF IER

•IForRFBufferAmplifiers

• Driver Stage for Power Amplifiers

• Oscillator Loop Amplifiers

1.59

1.61

0.365

TEXT*

2.80

3.00

0.650

2.60

3.00

*When Pin 1 is in
upper left,text
reads downward
(as shown).

3°MAX

0°MIN

0.35

0.55

1.44

1.04

0.15

0.05

4

AMPLIFIERS

GENERAL PURPOSE

0.127

Optimum Technology Matching® Applied

Si BJT GaAs MESFETGaAs HBT
Si Bi-CMOS

ü

RF IN

GND1

GND2

IPSET

SiGe HBT

1

2

3

Bias Circuits

4

Si CMOS

8

7

6

5

FOUT

ISET

VCC

NABLE

Functional Block Diagram

Package Style: SOT23-8

Features

• 700MHz to 2000MHz Operation

• 2.7V to 3.6V Single Supply

•+5dBmInputIP

at 3.0mA

3

•12dBGainat1950MHz

• 1.8dB Noise Figure at 1950MHz

•17dBGainStep

Ordering Information

RF2371 3V Low Noise Amplifier
RF2371 PCBA Fully Assembled EvaluationBoard

RF Micro Devices, Inc.
7625 Thorndike Road
Greensboro,NC 27409, USA

http://www.rfmd.com

Tel [phone]

Fax [phone]

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RF2371

Absolute Maximum Ratings

Parameter Rating Unit

Supply Voltage 4.0 V
SupplyCurrent 20 mA
Operating Ambient Temperature -40 to +85 ° C
Storage Temperature -40 to +150 °C

Preliminary

Caution! ESD sensitive device.

RF Micro Devices believes the furnishedinformation is correct and accurate
at the time of this printing. However, RF Micro Devices reservesthe right to
make changes to its products without notice. RF Micro Devices does not
assume responsibility for the use of the described product(s).

4

Parameter

Min. Typ. Max.

Overall

Frequency Range 700 to 2000 MHz

LNA Performance

Gain 10.5 12.5 dB
Noise Figure 1.6 dB
Input IP3 +4 +6 dBm At 2.9mA
Input P1dB -14 dBm
Input VSWR 5:1 dB (Noise match)

AMPLIFIERS

GENERAL PURPOSE

Output VSWR 1.5:1 dB
Off Mode Gain -5.0 dB V

Gain 17 dB Freq=836MHz
Noise Figure 1.6 dB
Input IP3 0 dBm

Specification

Unit Condition

T=27°C, VCC=2.7V, V
V

Freq=1.95GHz

ENABLE

ENABLE

=2.7V

=0V

ISELECT

=0V,

Current Control

Internal Current Setting “ON” CM OS Low V Voltage on ISELECT
External C urrent Setting “ON” CMOS High V Voltage on ISELECT
Current into ISELECT 1 µAV

ISELECT

=2.7V

Power Control

Power “ON” Voltage CMOS High V Voltage on ENABLE
Power “OFF” Voltage CMOS Low V Voltage on ENABLE
Current into ENABLE 1 µAV

ENABLE

=2.7V

Power Supply

Operating Voltage 2.7 to 3.6 V
Operating Current 2.9 5 mA V

Leakage Current 1 µAV

=2.7V,I n ternal current setting

CC

=0V

ENABLE

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Preliminary

RF2371

Pin Funct ion Description Interface Schematic

1RFIN
2GND1
3GND2

4 IPSET
5 ENABLE

6VCC
7 ISET
8RFOUT

RF input pin. This pin is not internally DC blocked and requires an
external blocking capacito r.

Ground connection for the LNA. Keep traces physically short a nd con­nect immediately to ground plane for best performance.

Ground connection for the bias circuits.
This pin selects theinternal current settingwhenCM OS level “low”, and

the external current setting when this pin is CMOS level “high”.
Power down control. This is a CMOS inpu t. When this pin is CMOS

“high” the d evice is enabled. When the level is CMOS “low” the device
is shut off and a controlled attenuator is turned on.

Power supply for the bias circuits.
This pin sets the current for the device.
RF output pin. Bias for the LNA is provided through this pin, hence it

should be connected to VCC through an inductor.

4

AMPLIFIERS

GENERAL PURPOSE

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RF2371

Preliminary

Application Information

The RF2371 may be configured to use either the internal current setting or the external current setting. This choice is
made by asserting IPSET, pin 4, to CMOS level“low” for the internal currentsetting or CMOS level “high” for the external
current setting.

Internal Current Setting

When IPSET is set to CMOS “low”, the internal current settings are chosen. This current draw is typically 2.9mA. In this
mode, the resistorR1 may be removedfrom the evaluation board schematic and ISET left floating. The condition for opti­mal IP3 is to use the internal current setting option and leavethe ISET pin open (no connect).

4

External Current Setting

The external current setting is configured by using the series resistor between ISET, pin7, and ground (refer to resistor
R1 in evaluation board schematic). The value of the resistormaybe changed to permit various operating currents up to a
maximum allowable current of 20mA. The table below gives approximate minimum R1 values to allow the 20mA maxi­mum current draw at various operating voltages.

AMPLIFIERS

GENERAL PURPOSE

Note: When the internal current setting was selected, the part tested drew 4.4mA, which is higher than typical

(2.9mA). Thus values of R1 given vary from part to part.

V

(V) Resistor R1 (Ω) Current Draw (mA)

CC

2.7 2.4k 20.1

3.0 2.7k 20.1

3.3 3.0k 20.0

3.6 3.3k 19.8

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Preliminary

Application Schemati c

1.95GHz

RF2371

V

CC

RF IN

IPSET

RF IN

IPSET

22 nF

10 nF

22 nF

82 nH

1

2

3

Bias Circuits

4

8

7

6

5

Application Schemati c

836MHz

1

2

3

Bias Circuits

4

8

7

6

5

3.3 nH

18 nH

V

CC

1.5 pF

1k

Ω

1pF

1k

Ω

V

CC

V

CC

RF OUT

ENABLE

RF OUT

ENABLE

4

AMPLIFIERS

GENERAL PURPOSE

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RF2371

Preliminary

Evaluation Board Schema t ic

(Download Bill of Materials from www.rfmd.com.)

VCC

4

L1

3.9 nH

8

7

6

5

AMPLIFIERS

J2

LNA INPUT

IPSET

IPSET

22 nF

ENABLE

C1

L2

10 nH

1

2

3

Bias Circuits

4

2371400-

VCC

GENERAL PURPOSE

ENVCC

2.6 V

+

C3

+

-

1nF

C4

1uF

C5

22 nF

VCC

2.7 V

+

-

C2

1.5 pF

R1

Ω

1k

P1

1
2
3
4

CON4

J1

LNA OUTPU

VCC

ENABLE

VCC
ENABLE

IPSET

GND

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Preliminary

RF2371

Evaluation Board Layout

Board Size 0.833” x 1.009”

Board Thickness 0.031”, Board Material FR-4

4

AMPLIFIERS

GENERAL PURPOSE

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4

RF2371

AMPLIFIERS

GENERAL PURPOSE

Preliminary

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