Rainbow Electronics MAX19985A User Manual

General Description

The MAX19985A high-linearity, dual-channel, downconversion mixer is designed to provide approximately

8.7dB gain, +25.5dBm of IIP3, and 9.0dB of noise figure for 700MHz to 1000MHz diversity receiver applications. With an optimized LO frequency range of 900MHz to 1300MHz, this mixer is ideal for high-side LO injection architectures in the cellular and new 700MHz bands. Low-side LO injection is supported by the MAX19985, which is pin-pin and functionally compatible with the MAX19985A.

In addition to offering excellent linearity and noise performance, the MAX19985A also yields a high level of component integration. This device includes two double-balanced passive mixer cores, two LO buffers, a dual-input LO selectable switch, and a pair of differential IF output amplifiers. On-chip baluns are also integrated to allow for single-ended RF and LO inputs.

The MAX19985A requires a nominal LO drive of 0dBm and a typical supply current of 330mA at VCC= +5.0V or 280mA at V

= +3.3V.

The MAX19985/MAX19985A are pin compatible with the MAX19995/MAX19995A series of 1700MHz to 2200MHz mixers and pin similar with the MAX19997A/ MAX19999 series of 1850MHz to 3800MHz mixers, making this entire family of downconverters ideal for applications where a common PCB layout is used across multiple frequency bands.

The MAX19985A is available in a 6mm x 6mm, 36-pin thin QFN package with an exposed pad. Electrical performance is guaranteed over the extended temperature range of TC= -40°C to +85°C.

Applications

850MHz WCDMA and cdma2000®Base Stations

700MHz LTE/WiMAX™ Base Stations

GSM850/900 2G and 2.5G EDGE Base Stations

iDEN

Base Stations

Fixed Broadband Wireless Access

Wireless Local Loop

Private Mobile Radios

Military Systems

Features

 700MHz to 1000MHz RF Frequency Range

 900MHz to 1300MHz LO Frequency Range

 50MHz to 500MHz IF Frequency Range

 8.7dB Typical Conversion Gain

 9.0dB Typical Noise Figure

 +25.5dBm Typical Input IP3

 +12.6dBm Typical Input 1dB Compression Point

 76dBc Typical 2LO-2RF Spurious Rejection at

= -10dBm

 Dual Channels Ideal for Diversity Receiver

Applications

 48dB Typical Channel-to-Channel Isolation

 Low -3dBm to +3dBm LO Drive

 Integrated LO Buffer

 Internal RF and LO Baluns for Single-Ended

Inputs

 Built-In SPDT LO Switch with 46dB LO1-to-LO2

Isolation and 50ns Switching Time

 Pin Compatible with the MAX19995/MAX19995A

Series of 1700MHz to 2200MHz Mixers

 Pin Similar to the MAX19997A/MAX19999 Series

of 1850MHz to 3800MHz Mixers

 Single +5.0V or +3.3V Supply

 External Current-Setting Resistors Provide Option

for Operating Device in Reduced-Power/ReducedPerformance Mode

MAX19985A

Dual, SiGe, High-Linearity, 700MHz to 1000MHz

Downconversion Mixer with LO Buffer/Switch

________________________________________________________________

Maxim Integrated Products

19-4185; Rev 0; 8/08

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

cdma2000 is a registered trademark of Telecommunications Industry Association.

WiMAX is a trademark of WiMAX Forum.

iDEN is a registered trademark of Motorola, Inc.

Typical Application Circuit and Pin Configuration appear at end of data sheet.

Denotes a lead-free/RoHS-compliant package.

EP = Exposed pad.

T = Tape and reel.

Ordering Information

PART TEMP RANGE PIN-PACKAGE

MAX19985AETX+ -40°C to +85°C 36 Thin QFN-EP*

MAX19985AETX+T -40°C to +85°C 36 Thin QFN-EP*

MAX19985A

Dual, SiGe, High-Linearity, 700MHz to 1000MHz Downconversion Mixer with LO Buffer/Switch

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

+3.3V SUPPLY DC ELECTRICAL CHARACTERISTICS

(

Typical Application Circuit

, VCC= 3.0V to 3.6V, TC= -40°C to +85°C. Typical values are at VCC= 3.3V, TC= +25°C, all parameters

are guaranteed by design and not production tested, unless otherwise 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.

Note 1: Based on junction temperature TJ= TC+ (θJCx VCCx ICC). This formula can be used when the temperature of the exposed

pad is known while the device is soldered down to a PCB. See the

Applications Information

section for details. The junction

temperature must not exceed +150°C.

Note 2: Junction temperature T

= TA+ (θJAx VCCx ICC). This formula can be used when the ambient temperature of the PCB is

known. The junction temperature must not exceed +150°C.

Note 3: 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.maxim-ic.com/thermal-tutorial

Note 4: T

is the temperature on the exposed pad of the package. TAis the ambient temperature of the device and PCB.

to GND...........................................................-0.3V to +5.5V

LO1, LO2 to GND ...............................................................±0.3V

Any Other Pins to GND...............................-0.3V to (V

+ 0.3V)

RFMAIN, RFDIV, and LO_ Input Power ..........................+15dBm

RFMAIN, RFDIV Current (RF is DC shorted

to GND through balun)....................................................50mA

Continuous Power Dissipation (Note 1) ..............................8.8W

(Notes 2, 3)..............................................................+38°C/W

(Note 3).....................................................................7.4°C/W

Operating Temperature Range (Note 4).....T

= -40°C to +85°C

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

Storage Temperature Range .............................-65°C to +150°C

Lead Temperature (soldering, 10s) .................................+300°C

+5.0V SUPPLY DC ELECTRICAL CHARACTERISTICS

(

Typical Application Circuit

, VCC= 4.75V to 5.25V, TC= -40°C to +85°C. Typical values are at VCC= 5.0V, TC= +25°C, all parame-

ters are production tested, unless otherwise noted.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Supply Voltage V

Supply Current I

LOSEL Input High Voltage V

LOSEL Input Low Voltage V

LOSEL Input Current IIH, I

4.75 5 5.25 V

-10 +10 µA

330 380 mA

0.8 V

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Supply Voltage V

Supply Current I

LOSEL Input High Voltage V

LOSEL Input Low Voltage V

R2 = R5 = 600Ω 3.0 3.3 3.6 V

Total supply current, VCC = 3.3V 280 mA

0.8 V

MAX19985A

Dual, SiGe, High-Linearity, 700MHz to 1000MHz

Downconversion Mixer with LO Buffer/Switch

_______________________________________________________________________________________ 3

RECOMMENDED AC OPERATING CONDITIONS

+5.0V SUPPLY AC ELECTRICAL CHARACTERISTICS

(

Typical Application Circuit

, VCC= +4.75V to +5.25V, RF and LO ports are driven from 50Ω sources, PLO= -3dBm to +3dBm,

= -5dBm, fRF= 700MHz to 1000MHz, fLO= 900MHz to 1200MHz, fIF= 200MHz, fRF< fLO, TC= -40°C to +85°C. Typical values

are at V

= +5.0V, PRF= -5dBm, P

= 0dBm, fRF=900MHz, fLO= 1100MHz, f

= 200MHz, TC=+25°C, all parameters are guaran-

teed by design and characterization, unless otherwise noted.) (Note 6)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

RF Frequency f

LO Frequency f

IF Frequency f

LO Drive Level P

(Note 5) 700 1000 MHz

(Note 5) 900 1300 MHz

U si ng M i ni - C i r cui ts TC 4- 1W- 17 4:1 tr ansfor m er as defined in the Typical Application Circuit, IF matching components affect the IF frequency range (Note 5)

Using alternative Mini-Circuits TC4-1W-7A 4:1 transformer, IF matching components affect the IF frequency range (Note 5)

(Note 5) -3 +3 dBm

100 500

50 250

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Conversion Power Gain G

Conversion Power Gain Variation vs. Frequency

G ai n V ar i ati on Over Tem p er atur eTCGTC = -40°C to +85°C -0.012 dB/°C

Noise Figure NF

Noise Figure Temperature Coefficient

Noise Figure Under Blocking Condition

Input 1dB Compression Point IP

Third-Order Input Intercept Point IIP3

fIF = 200MHz, fRF = 824MHz to 915MHz,

= -40°C to +85°C

fIF = 200MHz, fRF = 824MHz to 915MHz,

= +25°C (Note 9)

Flatness over any one of three frequency bands: f

= 824MHz to 849MHz,

= 869MHz to 894MHz,

= 880MHz to 915MHz (Note 9)

TC = -40°C to +85°C 9.2 11.5

= 850MHz, fIF = 200MHz,

= 0d Bm , TC = + 25°C , V

TC = -40°C to +85°C 0.018 dB/°C

+8dBm blocker tone applied to RF port,

= 900MHz, fLO = 1090MHz,

= -3dBm, f

= +5.0V (Note 7)

TC = -40°C to +85°C 10.0 12.6

TC = +25°C (Note 9) 11.0 12.6

fRF = 824MHz to 915MHz, f

- f

RF2

RF1

= -5dBm/tone, TC = -40°C to +85°C

= 824MHz to 915MHz,

- f

RF2

RF1

= -5dBm/tone, TC = +25°C (Note 9)

BLOCKER

= 1MHz, fIF = 200MHz,

∆G

1dB

= 800MHz,

7.0 8.7 10.2

7.7 8.7 9.7

0.15 0.3 dB

= + 5.0V

C C

22.5 25.5

23.5 25.5

9.0 10.3

18.8 22 dB

MHz

dBm

MAX19985A

Dual, SiGe, High-Linearity, 700MHz to 1000MHz Downconversion Mixer with LO Buffer/Switch

4 _______________________________________________________________________________________

+5.0V SUPPLY AC ELECTRICAL CHARACTERISTICS (continued)

(

Typical Application Circuit

, VCC= +4.75V to +5.25V, RF and LO ports are driven from 50Ω sources, PLO= -3dBm to +3dBm,

= -5dBm, fRF= 700MHz to 1000MHz, fLO= 900MHz to 1200MHz, fIF= 200MHz, fRF< fLO, TC= -40°C to +85°C. Typical values

are at V

= +5.0V, PRF= -5dBm, P

= 0dBm, fRF=900MHz, fLO= 1100MHz, f

= 200MHz, TC=+25°C, all parameters are guaran-

teed by design and characterization, unless otherwise noted.) (Note 6)

2LO-2RF Spur Rejection 2 x 2

3LO-3RF Spur Rejection 3 x 3

LO Leakage at RF Port

2LO Leakage at RF Port

3LO Leakage at RF Port

4LO Leakage at RF Port

LO Leakage at IF Port

RF-to-IF Isolation fRF = 824MHz to 915MHz (Note 10) 30 38 dB

LO-to-LO Isolation

Channel-to-Channel Isolation

LO Switching Time 50% of LOS E L to IF settl ed w i thi n 2 d eg r ees 50 1000 ns

RF Input Impedance Z

RF Input Return Loss

LO Input Impedance Z

LO Input Return Loss

IF Terminal Output Impedance Z

IF Return Loss

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

= 800MHz,

= 1000MHz,

= 900MHz

SPUR

= 800MHz,

= 1000MHz,

= 933.3MHz

SPUR

= 900MHz to 1300MHz, PLO = +3dBm

(Note 10)

fLO = 900MHz to 1200MHz, PLO = +3dBm (Note 10)

= 1200M H z to 1300M H z, P

L O

(Note 10)

= 900MHz to 1300MHz, PLO = +3dBm

(Note 10)

= 900MHz to 1300MHz, PLO = +3dBm

(Note 9)

= 900MHz to 1300MHz, PLO = +3dBm

(Note 10)

= +3dBm, P

LO1

= 900MHz, f

LO1

= -5dBm (Notes 8, 10)

RFM AIN ( RFD IV ) conver ted p ow er m easur ed at IFD IV ( IFM AIN ) , r el ati ve to IFM AIN ( IFD IV ) , al l unused p or ts ter m i nated to 50Ω ( N ote 9)

LO on and IF terminated into matched impedance

RF and IF terminated into matched impedance, LO port selected

RF and IF terminated into matched impedance, LO port unselected

Nominal differential impedance at the IC’s

IF output

RF terminated in 50Ω; transformed to 50Ω using external components shown in the

Typical Application Circuit

= +3dBm,

LO2

= 901MHz,

LO2

PRF = -10dBm -63 -76

= -5dBm

(Note 9)

PRF = -10dBm -65 -78

= -5dBm

(Note 9)

= + 3d Bm

L O

-58 -71

-60 -73

-40 -20 dBm

-38 -25

-35 -22

-50 -28 dBm

-25 -15 dBm

-35 -23 dBm

40 46 dB

40 48 dB

50 Ω

20 dB

50 Ω

200 Ω

18 dB

dBc

dBm

MAX19985A

Dual, SiGe, High-Linearity, 700MHz to 1000MHz

Downconversion Mixer with LO Buffer/Switch

_______________________________________________________________________________________ 5

+3.3V SUPPLY AC ELECTRICAL CHARACTERISTICS

(

Typical Application Circuit

, RF and LO ports are driven from 50Ω sources. Typical values are at VCC= +3.3V, PRF= -5dBm,

= 0dBm, fRF= 900MHz, fLO= 1100MHz, fIF= 200MHz, TC=+25°C, unless otherwise noted.) (Note 6)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Conversion Power Gain G

Conversion Power Gain Variation vs. Frequency

G ai n V ar i ati on Over Tem p er atur eTCGTC = -40°C to +85°C -0.012 dB/°C

Noise Figure NF 9.0 dB

Noise Figure Temperature Coefficient

Input 1dB Compression Point IP

Third-Order Input Intercept Point IIP3

2LO-2RF Spur Rejection 2 x 2

3LO-3RF Spur Rejection 3 x 3

Maximum LO Leakage at RF Port fLO = 900MHz to 1300MHz, PLO = +3dBm -40 dBm

M axi m um 2LO Leakag e at RF P or tf

Maximum LO Leakage at IF Port fLO = 900MHz to 1300MHz, PLO = +3dBm -34 dBm

Minimum RF-to-IF Isolation fRF = 824MHz to 915MHz 38 dB

LO-to-LO Isolation

Channel-to-Channel Isolation

LO Switching Time 50% of LOS E L to IF settl ed w i thi n 2 d eg r ees 50 ns

RF Input Impedance Z

RF Input Return Loss

LO Input Impedance Z

LO Input Return Loss

8.7 dB

0.15 dB

10.6 dBm

24.7 dBm

45 dB

48 dB

50 Ω

21 dB

50 Ω

∆G

1dB

Flatness over any one of three frequency bands: f

= 824MHz to 849MHz,

= 869MHz to 894MHz,

= 880MHz to 915MHz

TC = -40°C to +85°C 0.018 dB/°C

= 900MHz, f

RF1

= 200MHz, PRF = -5dBm/tone

= 800MHz,

= 1000MHz,

= 900MHz

SPUR

= 800MHz,

= 1000MHz,

= 933.333MHz

SPUR

= 900MHz to 1300MHz, PLO = +3dBm -42 dBm

= +3dBm, P

LO1

= 900MHz, f

LO1

RFM AIN ( RFD IV ) conver ted p ow er m easur ed at IFD IV ( IFM AIN ) , r el ati ve to IFM AIN ( IFD IV ) , al l unused p or ts ter m i nated to 50Ω

LO on and IF terminated into matched impedance

RF and IF terminated into matched impedance, LO port selected

RF and IF terminated into matched impedance, LO port unselected

= 901MHz,

RF2

PRF = -10dBm -74.9

= -5dBm -69.9

= -10dBm -78

= -5dBm -73

= +3dBm,

LO2

= 901MHz (Note 8)

LO2

dBc

MAX19985A

Dual, SiGe, High-Linearity, 700MHz to 1000MHz Downconversion Mixer with LO Buffer/Switch

6 _______________________________________________________________________________________

Note 5: Not production tested. Operation outside this range is possible, but with degraded performance of some parameters. See

the

Typical Operating Characteristics

. Performance is optimized for RF frequencies of 824MHz to 915MHz.

Note 6: All limits reflect losses of external components. Output measurements taken at IF outputs of

Typical Application Circuit

Note 7: Measured with external LO source noise filtered so the noise floor is -174dBm/Hz. This specification reflects the effects of

all SNR degradations in the mixer including the LO noise, as defined in the Application Note 2021:

Specifications and

Measurement of Local Oscillator Noise in Integrated Circuit Base Station Mixers

Note 8: Measured at IF port at IF frequency. LOSEL may be in any logic state. Note 9: Limited production testing. Note 10: Guaranteed by production testing.

+3.3V SUPPLY AC ELECTRICAL CHARACTERISTICS (continued)

(

Typical Application Circuit

, RF and LO ports are driven from 50Ω sources. Typical values are at VCC= +3.3V, PRF= -5dBm,

= 0dBm, fRF= 900MHz, fLO= 1100MHz, fIF= 200MHz, TC=+25°C, unless otherwise noted.) (Note 6)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

IF Terminal Output Impedance Z

IF Output Return Loss

Nominal differential impedance at the IC’s

IF output

RF terminated in 50Ω; transformed to 50Ω using external components shown in the

Typical Application Circuit

200 Ω

17 dB

MAX19985A

Dual, SiGe, High-Linearity, 700MHz to 1000MHz

Downconversion Mixer with LO Buffer/Switch

_______________________________________________________________________________________ 7

Typical Operating Characteristics

(

Typical Application Circuit

, VCC= +5.0V, PLO= 0dBm, PRF= -5dBm, LO is high-side injected for a 200MHz IF, TC=+25°C, unless

otherwise noted.)

CONVERSION GAIN vs. RF FREQUENCY

TC = -30°C

CONVERSION GAIN (dB)

TC = +85°C

700 1000

TC = +25°C

RF FREQUENCY (MHz)

INPUT IP3 vs. RF FREQUENCY

TC = +85°C

CONVERSION GAIN vs. RF FREQUENCY

CONVERSION GAIN (dB)

700 1000

VCC = 4.75V, 5.0V, 5.25V

900800

RF FREQUENCY (MHz)

INPUT IP3 vs. RF FREQUENCY

PRF = -5dBm/TONE

VCC = 5.25V

900800

PRF = -5dBm/TONE

MAX19985A toc01

CONVERSION GAIN (dB)

MAX19985A toc04

CONVERSION GAIN vs. RF FREQUENCY

PLO = -3dBm, 0dBm, +3dBm

700 1000

RF FREQUENCY (MHz)

900800

INPUT IP3 vs. RF FREQUENCY

PRF = -5dBm/TONE

MAX19985A toc02

MAX19985A toc05

MAX19985A toc03

MAX19985A toc06

INPUT IP3 (dBm)

TC = -30°C

700 1000

TC = +25°C

900800

RF FREQUENCY (MHz)

NOISE FIGURE vs. RF FREQUENCY

NOISE FIGURE (dB)

TC = -30°C

700 1000

TC = +85°C

TC = +25°C

900800

RF FREQUENCY (MHz)

INPUT IP3 (dBm)

MAX19985A toc07

NOISE FIGURE (dB)

PLO = +3dBm, 0dBm

700 1000

RF FREQUENCY (MHz)

PLO = -3dBm

900800

NOISE FIGURE vs. RF FREQUENCY

PLO = -3dBm, 0dBm, +3dBm

700 1000

RF FREQUENCY (MHz)

900800

MAX19985A toc08

INPUT IP3 (dBm)

VCC = 4.75V

700 1000

RF FREQUENCY (MHz)

VCC = 5.0V

900800

NOISE FIGURE vs. RF FREQUENCY

NOISE FIGURE (dB)

700 1000

VCC = 4.75V, 5.0V, 5.25V

900800

RF FREQUENCY (MHz)

MAX19985A toc09

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