Datasheet RF2484, RF2484PCBA Datasheet (RF Micro Devices)

ü

5-29

5

MODULATORS AND

UPCONVERTERS

Preliminary

Product Description

Ordering Information

Typical Applications

Features

Functional Block Diagram

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

Tel [phone]

Fax [phone]

http://www.rfmd.com

Optimum Technology Matching® Applied

Si BJT GaAs MESFETGaAs HBT
Si Bi-CMOS

SiGe HBT

Si CMOS

GND

QREF

IREF

ISIG

QSIG

GND

VCC

PD

RF OUT

GND

GND

GND

VCC

GND

GND

LO

Σ

-45°
+45°

5

13

12

11

10

14

7 86 9

15161

2

3

4

RF2484

DIRECT QUADRATURE MODULATOR

• Dual-Band CDMA Base Stations

• TDMA/TDMA-EDGE Base Stations

• GSM-EDGE/EGSM Base Stations

• W-CDMA Base Stations

• WLAN and WLL Systems

• GMSK,QPSK,DQPSK,QAM Modulation

The RF2484 is a monolithic integrated quadrature modu­lator IC capable of universal direct modulation for high­frequency AM, PM, or compound carr iers. This low-cost
IC features excellent linearity, noise floor, and over-tem­perature carrier suppression performance. The device
implements differential amplifiers for the modulation
inputs, 90° carrier phase shift network, carrier limiting
amplifiers, two matched double-balanced mixers, sum­ming amplifier, and an output RF amplifier which will drive
50 Ω from 800MHz to 2500MHz. It is packaged in a small
industry-standard LCC 16-pin plastic package.

• Typical Carrier Suppression >35dBc,
Sideband Suppression >35dBc over
temperature with highly linear operation

• Noise Floor better than -152 dBm/Hz
from 800MHz to 2200MHz

• Single 5V Power Supply

RF2484 Direct Quadrature Modulator
RF2484 PCBA Fully Assembled Evaluation Board

5

Rev A2 010829

3.75

3.75

+

1.50 SQ

4.00

4.00

1

0.45

0.28

3.20

1.60

0.75

0.50

12°

INDEX AREA

3

1.00

0.90

0.75

0.65

0.05

0.00

NOTES:

5 Package Warpage: 0.05 max.

4 Pins 1 and 9 are fused.

Shaded Pin is Lead 1.1
Dimension applies to plated terminal and is measured between

0.10 mm and 0.25 mm from terminal tip.

2

The terminal #1 identifier and terminal numbering convention
shall conform to JESD 95-1 SPP-012. Det ails of terminal #1
identifier are optional, but must be loc ated within the zone
indicated. The identif ier may be either a mold or marked
feature.

3

0.80
TYP

2

1

Dimensions in mm.

Package Style: LCC, 16-Pin

Preliminary

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RF2484

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MODULATORS AND

UPCONVERTERS

Absolute Maximum Ratings

Parameter Rating Unit

Supply Voltage -0.5 to +7.5 V

DC

Input LO and RF Levels +10 dBm
Operating Ambient Temperature -40 to +85 °C
Storage Temperature -40 to +150 °C

Parameter

Specification

Unit Condition

Min. Typ. Max.

LO Input

T= 25°C, VCC=5V,V

REF

=4.1V;IandQ

driven single-ended
Frequency Range 800 2500 MHz
Power Level -6 +6 dBm
Input Impedance 45- j95 Ω At 880MHz

52-j54 Ω At 1960MH z
58-j50 Ω At 2140MH z
63-j40 Ω At 2400MH z

Modulation Input

Frequency Range DC 250 MHz
Reference Voltage (V

REF

)4.1V

Input Resistance 30 kΩ
Input B ias Current 40 µA

RF Output (880MHz)

LO= -5dBm at 880MHz; Single s ideband

testing unless otherwise noted
CDMA Output Channel Power -12 dBm For ACPR=-72dBc; I&Q Amplitude =1.1V

PP

(single-ended)
CDMA ACPR -72 dBc Channel Power=-12dBm; see TestSetup for

detailed information
Carrier Suppression 50 dBc T=25°C; P

OUT

=-10 dBm; optimized I,Q DC

offsets
Carrier Suppression

over Temperature

35 dBc Temperature cycled from -40°C to +85°C

after optimization at T=25°C; P

OUT

=-10 dBm

Sideband Suppression 50 dBc T=25°C; P

OUT

=-10 dBm; optimized I,Q

amplitude and phase balanc e
Sideband Suppression

over Temperature

35 dBc Temperature cycled from -40°C to +85°C

after optimization at T=25°C; P

OUT

=-10 dBm

Broadband Noise Floor -152.5 dBm/Hz At 20MHz offset, 30kHz res BW, V

CC

=5V;

ISIG, QSIG, IREF, and QREF tied to V

REF

EVM 2.3 % See Test Setup for detailed information
Phase Error 1 ° RMS See Test Setup for detailed information
Rho .9993 See Test Setup for detailed info rmation
Output Impedance 28- j72 Ω

RF Output (1960 MHz)

LO=-5 dBm at 1960MHz; Single sideband

testing unless otherwise noted
PCS CDMA Output Power -13 dBm For ACPR=-72dBc; I&Q Amplitude=1.2V

PP

(single-ended)
PCS CDMA ACPR -72 dBc Channel Power=-13dBm; see Test Setup for

detailed information
Carrier Suppression 50 dBc T=25°C; P

OUT

=-13 dBm; optimized I,Q DC

offsets
Carrier Suppression

over Temperature

35 dBc Temperature cycled from -40°C to +85°C

after optimization at T=25°C; P

OUT

=-13 dBm

Sideband Suppression 50 dBc T=25°C; P

OUT

=-13 dBm; optimized I,Q

amplitude and phase balanc e
Sideband Suppression

over Temperature

35 dBc Temperature cycled from -40°C to +85°C

after optimization at T=25°C; P

OUT

=-13 dBm

Caution! ESD sensitive device.

RF Micro Devices believesthe furnished information is correct and accurate
at the time of this printing. However, RF Micro Devices reserves the right to
make changes to its products without notice. RF Micro Devices does not
assume responsibilityfor the use of the described product(s).

Preliminary

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MODULATORS AND

UPCONVERTERS

Parameter

Specification

Unit Condition

Min. Typ. Max.

RF Output (1960MHz)
cont’d

Broadband Noise Floor -154.5 dBm/Hz At 20MH z offset, 30kHz res BW, VCC=5V;

ISIG, QSIG, IREF, and QREF tied to V

REF

EVM 2.3 % See Test Setup for detailed information
Phase Error 1 ° RMS See Test Setup for detailed information
Rho .9988 See Test Setup for detailed information
Output Impedance 46- j22 Ω

RF Output (2140MHz)

LO= -5dBm at 2140MHz; Singl e sideband
testing unless otherwise noted

W-CDMA Output Channel Power -16 dBm For ACPR=-60dBc; I&Q Amplitude=1.4V

PP

(single-ended)

W-CDMA ACPR -60 dBc Channel Power=-16dBm; see TestSetup for

detailed information

Carrier Suppression 50 dBc T=25°C; P

OUT

=-13dBm; optimized I,Q DC

offsets

Carrier Suppression

over Temperature

35 dBc Temperature cycled from -40°C to +85°C

after optimization at T=25°C; P

OUT

=-13dBm

Sideband Suppression 50 dBc T=25°C; P

OUT

=-13dBm; optimized I,Q

amplitude and phase balance

Sideband Suppression

over Temperature

35 dBc Temperature cycled from -40°C to +85°C

after optimization at T=25°C; P

OUT

=-13dBm

Broadband Noise Floor -152 dBm/Hz At 20MHz offset, 30kHz res BW, VCC=5V;

ISIG, QSIG, IREF, and QREF tied to V

REF

EVM 5.9 % See Test Setup for detailed information
Phase Error 2.4 ° RMS See Test Setup for detailed information
Rho .9961 See Test Setup for detailed information
Output Impedance 58- j16 Ω

Power Down

Turn On/Off Time 100 ns
PD Input Resistance 50 kΩ
Power Control “ON” 2.8 V Threshold voltage
Power Control “OFF” 1.0 1.2 V Threshold voltage

Power Supply

Voltage 5.0 V Specifications

4.5 6.0 V Operating Limits

Current 66 70 mA

25 µA Power Down

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UPCONVERTERS

Pin Function Description Interface Schematic

1GND

Ground connection. This pin should be connected directly to the
ground plane.

2GND

Same as pin 1.

3GND

Same as pin 1.

4LO

The input of the phase shifting network. This pin has an internal DC
blocking capacitor. This port is voltage-driven so matching at different
frequencies is generally not required.

5GND

Same as pin 1.

6VCC

Powersupply. An external capacitor is needed if no other low frequ ency
bypass capacitor is nearby.

7PD

Power Down control. When this pin is "low," all circuits are shut off. A
"low" is typically 1.2V or less at room temperature.When this pin is
"high"(V

CC

), all circuits are operating normally. If PD is below VCC, out-

put power and performance will be degraded. Operating in this region
is not recommended, although it might be useful in some applications
where power control is req uired.

8RFOUT

RF Output. This pin has an internal DC blocking capacitor. At some fre­quencies, external matching may be needed to optimize output power.
A s mall amount of DC current may be present at this output. As a
result, if the voltage at this pin is measured using a high impedance
probe, some DC voltage may be observed at this output.

9GND

Same as pin 1.

10 VCC

Same as pin 6.

11 GND

Same as pin 1.

12 GND

Same as pin 1.

13 Q SIG

Baseband input to the Q mixer. This pin is DC coupled. The input drive
level determines output power and linearity performance; for better car­rier suppression, sideband suppression, and dynamic range, the drive
level should be as high as possible to meet the required linearity perfor­mance. The recommended DC level for this pin is 4.1V.

For optimum carrier suppression, the DC voltages on I REF, Q REF, I
SIG and Q SIG should be adjusted slightly to compensate for inherent
undesired internal DC offs ets; for optimum sideband suppression,
phase and signal amplitude on IREF, Q REF, I SIG and Q SIG should
be adjusted slightly to compensate for inherent undesired internal off­sets. See RFMD AN0001 for more detail.

14 I SIG

Baseband input to the I mixer. This pin is DC coupled. The input drive
level determines output power and linearity performance; for better car­rier suppression, sideband suppression, and dynamic range, the drive
level should be as high as possible to meet the required linearity perfor­mance. The recommended DC level for this pin is 4.1V; see pin 13 fo r
more information.

15 I REF

Reference voltage for the I mixer. This voltage should be the same as
the DC voltage supplied to the I SIG pin. A voltage of 4.1V is recom­mended; see pin 13 for more information.

The SIG and RE F inputs are inputs of a differential amplifier. Therefore
the REF and SIG inputs are interchangeable. If swapping the I SIG and
I REF pins, the Q SIG and Q REF also need to be swapped to maintain
the correct phase. It is also possible to drive the SIG and RE F inputs in
a d ifferential mode. This will increase the gain.

LO

200 Ω

PD

V

CC

RF OUT

100 Ω

1p

V

CC

100 Ω

1p

V

CC

100 Ω

1p

V

CC

Preliminary

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5

MODULATORS AND

UPCONVERTERS

Pin Function Description Interface Schematic

16 Q REF

Reference voltage for the Q mixer. This voltage should be the same as
the DC voltage supplied to the Q SIG pin. A voltage of 4.1V is recom­mended; see pin 13 for more information.

Pkg

Base

GND

Ground connection. The package base should be connected to the
ground plane.

100 Ω

1p

V

CC

Preliminary

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5

MODULATORS AND

UPCONVERTERS

CDMA/W-CDMA Test Setup

General

The above setup was used to evaluate the RF2484
under CDMA and W-CDMA modulation conditions.
Due to test equipment limitations, a DC-level shifting
board was required to provide the appropriate DC ref­erence voltage (4.1V) for the I and Q pins. I and Q
were driven single-endedly; differential drive may
improve perfor mance. A PC-controlled Rohde &
Schwarz AMIQ generated the CDMA I and Q signals.
In order to reduce AMIQ noise contributions to adja­cent channel power, W-CDMA baseband signals were
filtered using a high order low pass filter before appli­cation to the R F2484.

EVM, Phase Error, and Rho

To measure EVM, phase error, and Rho, signals were
generated using the AMIQ and decoded with the Agi­lent VSA. For CDMA Cellular and PCS, I and Q input
signals were generated with the Pilot Channel active,
32x oversampling and base station equifilters. For W­CDMA, the Common Pilot Channel was active with 8x
oversampling and a root cosine filter. In all cases, rela­tive signal amplitude levels were adjusted to optimize
signal quality.

CDMA Modulation Setup (Cellular and PCS)

To measure ACPR, I and Q input signals were gener­ated using the following settings:

• Pilot Channel active

• Sync Channel active

• Paging Channel active

• 6 Traffic Channels active

• 32x Oversampling

• Base Station equifilter

W-CDMA Modulation Setup

To measure W-CDMA ACPR, I and Q input signals
were generated using the following settings in the
AMIQ:

• P-CPICH (Common Pilot Channel) active

• P-SCH (Sync Channel) active

• P-CCPCH (Primary Common Control Physical
Channel) active

• P-ICH (Page Indicator Channel) Active

• DL-DPCCH (Dedicated Physical Control Channel)
active

• 6 DPCH (Dedicated PhysicalChannels) active

•8xOversampling

Rohde & Schwarz

AMIQ 1110.2003.02

RF2484 DC Level Shift

Control Board

RF2484

Evaluation Board

Rohde & Schwarz

FSIQ 1119.6001.26

Hewlett-Packard

8665B

ISIG

RF OUT

LO IN

IREF QSIG QREF

Agilent 66332A

VCC
VPD

Hewlett-Packard

6624A

Agilent 89441

Vector Signal Analyzer

Preliminary

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5

MODULATORS AND

UPCONVERTERS

Application Schematic

-45°
+45°

5

13

12

11

10

14

7 86 9

15161

2

3

4LO

VCC
PD RF OUT

VCC

QSIG

ISIG

QREF

IREF

100 nF3pF

100 nF3pF

100 nF3pF

100 nF 100nF

Σ

Preliminary

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5

MODULATORS AND

UPCONVERTERS

Evaluation Board Schema t ic

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

VCC

VREF/QREF

IREF

C8

100 nF

C7

3pF

C6

100 nF

C5

3pF

C2

100 nF

C1

3pF

C3

3pFC4100 nF

J2

LO

J1

RFOUT

VCC

J4

QSIG

J3

ISIG

R1a*

0 Ω

R1

0 Ω

U1

-45°
+45°

5

13

12

11

10

14

7 86 9

15161

2

3

4

Σ

P1

1
2
3

CON3

P1-1 VCC

GND
GND

P2

1
2
3

CON3

P2-3 IREF

GND

P2-1 VREF/QREF

2484400-

NOTES:

1. R1 is installed for non-independent control of I and Q
reference voltages.
R1a gives independent control of reference voltages.

2. Components with * following the reference designator
should not be populated on the evaluation board.

Preliminary

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5

MODULATORS AND

UPCONVERTERS

Evaluation Board Layout

Board Size 2.0" x 2.0"

Board Thickness 0.028”, Board Material FR-4

Preliminary

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RF2484

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5

MODULATORS AND

UPCONVERTERS

RF2484 CellularCDMA Spectra at VariousOutput Levels

(ACPR @ 885kHz, Vcc= 5.0V, Vref= 4.1V, T = 25°C)

-100

-90

-80

-70

-60

-50

-40

-30

-20

877.5 878 878.5 879 879.5 880 880.5 881 881.5 882 882.5

Frequency (MHz)

Power (dBm)

CP = -10.6dBm;
ACPR = -70 dBc

CP = -12.0dBm;
ACPR = -72 dBc

CP = -14.7dBm;
ACPR = -73 dBc

CP = -9.5dBm;
ACPR = -68 dBc

Note: Below~-90dBm,
test setup noise inhibits accurate
ACP measurement.

RF2484 Output Power versus I, Q Input Voltage Level

(Vcc = 5.0V, Vref = 4.1V,T = 25°C,Single Sideband)

-20

-15

-10

-5

0

5

0 200 400 600 800 1000 1200 1400 1600

I, Q Input Voltage Level (mVp)

SSB Output Power (dBm)

880 MHz
1960 MHz
2140 MHz

RF2484 PCS CDMA Spectra at Various Output Levels

(ACPR@ 885 kHz, Vcc = 5.0V,Vref = 4.1V,T = 25°C)

-100

-90

-80

-70

-60

-50

-40

-30

-20

1957.5 1958 1958.5 1959 1959.5 1960 1960.5 1961 1961.5 1962 1962.5

Frequency (MHz)

Power (dBm)

CP = -12.9dBm;
ACPR = -72 dBc

CP = -14.3dBm;
ACPR = -73 dBc

CP = -11.1dBm;
ACPR = -71 dBc

R

F2484 Output ChannelPowervs I, Q Input Voltage Level

(Vcc = 5.0V, Vref = 4.1V,T = 25°C,CDMA/W-CDMA Mod.)

-30

-25

-20

-15

-10

-5

250 500 750 1000 1250 1500 1750 2000 2250 2500

I, Q I nputVoltage Level (mVpp)

Output Channel Power (dBm)

880 MHz CDMA Signal

1960 MHz CDMA Signal

2140 MHz W-CDMA Signal