max211a fm autootive lonoise apliier - maxim integrated · pdf filemax211a fm autootive...

MAX2181A FM Automotive Low-Noise Amplifier

General DescriptionThe MAX2181A is a highly integrated FM variable-gain low-noise amplifier ideal for use in automotive FM and FM-diversity active antenna applications. The device features an FM signal path, providing 30dB of gain range, controlled by an on-chip power detector. The FM signal path covers 76MHz to 162.5MHz.The device is available in a small, 3mm x 3mm, TQFN package and operates over the extended industrial tem-perature range (-40ºC to +85ºC).

Applications AutomotiveActiveAntenna AutomotiveHeadUnit

Features +5V Supply Voltage Integrated AGC Function Eliminates

External Pin Diodes High Dynamic Range Low-Noise, Sub 3dB Noise Figure Low External BOM Small Package (3mm x 3mm TQFN) Integrated Power Detector

19-6612; Rev 0; 2/13

Simplified Block Diagram

Ordering Information appears at end of data sheet.

For related parts and recommended products to use with this part, refer to www.maximintegrated.com/MAX2181A.related.

EVALUATION KIT AVAILABLE

DET

FMOUTPUT

MAX2181AVCC

http://www.maximintegrated.com/MAX2181A.related


www.maximintegrated.com Maxim Integrated 2

DC Electrical Characteristics(MAX2181A Typical Application Circuit as shown, VDD = 4.75V to 5.25V, TA = -40ºC to +85ºC, unless otherwise noted. Typical values are at VDD = 5V, TA = +25ºC.) (Note 2)

Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial.

VDD, FMBYPASS,FMOUT......................................-0.5V to +6VShort-CircuitProtectionFMOUT .................................. IndefiniteFMIN ............................................................................. 130dBµVContinuous Power Dissipation (TA = +70ºC) 16 TQFN (derate 20.8mW/ºC above +70ºC) ..........1666.7mWθJC (Junction to Case) (Note 1) ........................................7ºC/WθJA (Junction to Ambient) (Note 1)..................................48ºC/W

Operating Temperature Range ..........................-40ºC to +105ºCJunction Temperature ...................................................... +150ºCStorage Temperature Range .............................-65ºC to +165ºCLead Temperature (TQFN only, soldering, 10s) .............. +300ºCSoldering Temperature (reflow) ....................................... +260ºC

Absolute Maximum Ratings

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.

CAUTION! ESD SENSITIVE DEVICE

PARAMETER CONDITIONS MIN TYP MAX UNITS

SUPPLY VOLTAGE (VDD)VDD Operational range 4.75 5 5.25 VSupply Current 56 68 mAGAIN CONTROL AND AGC CONTROL (FMDET, FMGAIN, FMAGC)

FMDETGround -65

µAVDD 50

FMGAIN

Ground -50 µA

Open 2.5 V

VDD 50 µA

FMAGCGround -50

µAVDD 50

http://www.maximintegrated.com/thermal-tutorial



AC Electrical Characteristics(MAX2181A Typical Application Circuit, VDD = 4.75V to 5.25V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VDD = 5V, loadimpedance=50Ω,FMgainconnectedtoground,tunedfor87MHzto108MHz,TA = +25°C.) (Note 2)

Note 2: Min and max values are production tested at TA = -40ºC, +25ºC, and +85ºC.Note 3: Guaranteed by design and characterization.Note 4: Tuned for 76MHz to 90MHz

PARAMETER CONDITIONS MIN TYP MAX UNITS

Frequency Range 76 162.5 MHz

Power Gain Maximum

fIN = 97MHz, FMGAIN connected to VDD 6 8.3 10

dBfIN = 97MHz, FMGAIN = open 5 7.2 9

fIN = 97MHz, FMGAIN = connected to ground 4 6 8

Gain Flatness

76MHz to 90MHz (Notes 3, 4) 0.5

dB87MHz to 108MHz (Note 3) 0.5

162.5MHz relative to 97MHz 3.2

Noise Figure fIN = 97MHz, TA = +25ºC 2.5 dB

Input Return Loss 50Ωsource 10 dB

Output Return Loss 50Ωload 15 dB

Gain-Control Range fIN = 97MHz 28 32 dB

IMD3 VIN = +120dBµV/tone, +100dBµV AGC threshold, 99.5MHz and 100.5MHz tones 66 dBc

AGC Threshold (See Table 2)Minimum output threshold 92

dBµVMaximum output threshold 107

AGC Threshold Variation Relative to 97MHz tone (76MHz to 108MHz) ±0.3 dB


Maxim Integrated 4www.maximintegrated.com

Typical Operating Characteristics(MAX2181A Typical Application Circuit, VDD = 5V, tuned for 87MHz - 108MHz, FM gain connected to ground, TA = +25°C, unless other-wise noted.)

SUPPLY CURRENTvs. TEMPERATURE

MAX

2181

A to

c01

SUPP

LY C

URRE

NT (m

A)

52

53

54

55

56

57

51

TEMPERATURE (ºC)1007550250-25-50 125

VDD = 5.25V

VDD = 5.0V

VDD = 4.75V

NOISE FIGURE vs. FREQUENCY87MHz TO 108MHz TUNING

MAX

2181

A to

c04

FREQUENCY (MHz)

NOIS

E FI

GURE

(dB)

150100

2.2

2.4

2.62.8

3.0

3.23.4

3.6

3.8

4.0

2.050 200

VFMGAIN = 0V

FMGAIN = HI-ZVFMGAIN = 5V

NOISE FIGURE vs. FREQUENCY76MHz TO 90MHz TUNING

MAX

2181

A to

c07

FREQUENCY (MHz)

NOIS

E FI

GURE

(dB)

150100

2.2

2.4

2.62.8

3.0

3.23.4

3.6

3.8

4.0

2.050 200

VFMGAIN = 0V

FMGAIN = HI-Z

VFMGAIN = 5V

AGC ATTACK POINT vs. FREQUENCY87MHz TO 108MHz TUNING

MAX

2181

A to

c08

FREQUENCY (MHz)

ATTA

CK P

OINT

(dBµ

V)

100 1059590

92

94

9698

100

102104

106

108

110

9085 110

R = 71kΩ

R = 62kΩ

R = 51kΩ

R = 43kΩ

R = 33kΩR = 22kΩ

R = 13kΩR = 0Ω

OUTPUT POWER, IM2, AND IM3vs. INPUT POWER CLOSED LOOP

MAX

2181

A to

c09

OUTP

UT P

OWER

, IM2,

AND

IM3 (

dBµV

)

20

40

60

80

100

120

0

INPUT POWER (dBµV)115105958575 125

OUTPUT POWER

INPUT TONES AT99MHz AND 100MHz

IM3

IM2 (A-B)

GAIN vs. FREQUENCY76MHz TO 90MHz TUNING

MAX

2181

A to

c05

FREQUENCY (MHz)

GAIN

(dB)

150100

3

4

5

6

7

8

250 200

T = +25°C

T = +105°C

= -40°CT

T = +85°C


MAX

2181

A to

c06

FREQUENCY (MHz)

GAIN

(dB)

150100

3

4

5

6

7

8

9

10

250 200

VFMGAIN = 5V

VFMGAIN = 0V

FMGAIN = HI-Z


MAX

2181

A to

c02

GAIN

(dB)

3

4

5

6

7

8

2

FREQUENCY (MHz)15010050 200

T = +85°C

T = +25°CT = -40°C

T = +105°C


MAX

2181

A to

c03

FREQUENCY (MHz)

GAIN

(dB)

150100

3

4

5

6

7

8

9

10

250 200

VFMGAIN = 5V

VFMGAIN = 0V

FMGAIN = HI-Z



Pin Description

Pin Configuration

PIN NAME FUNCTION

1 RBIAS Connecta1%tolerance20kΩresistortoground.

2 FMIN FMInput.ACcoupletoFMinputbandpassfilter.

3 GND Ground

4 FMGAIN FM Gain Trim. Connect to ground, leave open, or connect to VDD for the desired FM gain.

5–7, 9, 14–16 N.C. No Connection to Die. Suggested thermal path on Layer 1 of PCB for packages exposed pad to thermal sink.

8 FMAGC FM AGC Control Line. Connect a 1µF capacitor to ground.

10 FMOUT FM VGA Output

11 FMDET FM Attack Point Trim. Connect the desired resistor to ground.

12 FMBYPASS Connect a 10µF and 1000pF capacitor to ground.

13 VDD Supply Voltage

— EP Exposed Pad. Ground.

15

16

14

13

5

6

7

GND

FMGA

IN

8

RBIA

S

FMOU

T

N.C.

FMBY

PASS

1 3

N.C.

4

12 10 9

N.C.

N.C.

FMAGC

N.C.

N.C.

N.C.FM

INFM

DET

2

11

VDD

TQFN

MAX2181A

TOP VIEW

+



Detailed DescriptionSetting Signal Path Gain and AGC Attack PointThe MAX2181A allows independent variation of the gain and AGC attack points on the FM signal path. Gain and attack point are adjusted by changing the conditions on the FMGAIN and FMDET pins.

FM Signal PathTypical FM gain can be set using the FMGAIN pin as shown in Table 1. The output attack point of the FM signal path is adjusted by changing the resistor RFMDET, connected to the FMDET pin. Table 2 shows the attack point associated with several resistor values.

Layout RecommendationsFor best performance, the device must be mounted on a PCB that is designed for a low thermal resistance. The backside ground of the MAX2181A should be connected to a thermal ground plane on the PCB using at least nine plated through holes. Refer to www.maximintegrated.com for the MAX2181A Evaluation Kit schematic, Gerber data, PADS layout file, and BOM information.

Table 1. FM Signal Path Gain

Table 2. FM Signal Path Attack Point

PIN FMGAIN FM GAIN (dB, TYP)

Ground 6.0

Open 7.2

VDD 8.3

RFMDET (kΩ) FM OUTPUT ATTACK POINT (dBµV, TYP)

0 92

13 93.5

22 95

33 97

43 99

51 101.5

62 104

71 107

http://www.maximintegrated.com



Typical Application Circuit

15

16

14

13

5

6

7

8

20kΩ

62Ω

FMOUTPUT

105Ω

L2C1

FM INPUT

FMIN

GND

FMGA

IN

1 3

N.C.

4

12 10 9

N.C.

N.C.

FMAGC

N.C.

N.C.

FMOU

T

FMDE

T

FMBY

PASS

FMBYPASS

2

11

VDD

MAX2181A

+N.C.

N.C.

470pF

VDD

0.1µF

10µF

1µF

C251pF

L1470µH

RBIA

SFMBYPASS

TUNINGFOR 87MHz TO 108MHz C1 = 27pF L2 = 82nHFOR 76MHz TO 90MHz C1 = 33pF L2 = 100nH



Ordering Information Package InformationFor the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status.

+Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. /V denotes an automotive qualified part.

PACKAGE TYPE

PACKAGE CODE

OUTLINE NO.

LAND PATTERN NO.

16 TQFN T1633+2 21-0136 90-0030

PART TEMP RANGE PIN-PACKAGE

MAX2181AETE+ -40°C to +85°C 16 TQFN-EP*

MAX2181AETE/V+ -40°C to +85°C 16 TQFN-EP*

http://www.maximintegrated.com/packages

http://pdfserv.maximintegrated.com/package_dwgs/21-0136.PDF

http://pdfserv.maximintegrated.com/land_patterns/90-0030.PDF

Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.

Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.


© 2013 Maxim Integrated Products, Inc. 9

Revision HistoryREVISIONNUMBER

REVISIONDATE DESCRIPTION PAGES

CHANGED0 2/13 Initial release —

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.

max211a fm autootive lonoise apliier - maxim integrated · pdf filemax211a fm autootive...

Documents