RF2424 datasheet, PDF - EEWORLD Datasheet

RF2424

5

Typical Applications

• Digital Communications Systems

• GMSK,QPSK,DQPSK,QAM Modulation

• GSM and D-AMPS Systems

• Image-Reject Upconverters

• Spread Spectrum Communication Systems • AM, SSB, DSB Modulation

UHF QUADRATURE MODULATOR

Product Description

The RF2424 is a monolithic integrated quadrature modu-

lator IC capable of universal direct modulation for high-

frequency AM, PM, or compound carriers. Maximum out-

put power is +7.5dBm, which is achieved with low input I

and Q signal levels. This low-cost IC implements differen-

tial amplifiers for the modulation inputs, 90° carrier phase

shift network, carrier limiting amplifiers, two matched dou-

ble-balanced mixers, summing amplifier, and an output

RF amplifier which will drive 50Ω from 700MHz to

1000MHz.

0.157

0.150

0.012

0.008

0.196

0.189

0.025

-A-

0.0098

0.0040

5

MODULATORS AND

0.2440

0.2284

0.0688

0.0532

8° MAX

0°MIN

0.050

0.016

0.0098

0.0075

NOTES:

1. Shaded lead is Pin 1.

2. All dimensions are excluding mold flash.

3. Lead coplanarity - 0.005 with respect to datum "A".

Optimum Technology Matching® Applied

ü

Si BJT

Package Style: SSOP-16

GaAs HBT

SiGe HBT

GaAs MESFET

Si CMOS

Si Bi-CMOS

Features

• Single 2.7V to 5.5V Power Supply

• +7.5dBm Output Power

• No Tuning Required

• Low LO Input Level

• Digitally Controlled Power Down Mode

• 700MHz to 1000MHz Operation

I REF 1

Q REF 2

VCC1 3

MIXOUT 4

GND1 5

GND1 6

LO 7

GND3 8

-45°

+45°

16 ISIG

POWER

CONTROL

15 QSIG

14 GND1

13 VCC2

Σ

12 PD

11 GND1

10 GND2

9 RFOUT

Ordering Information

RF2424

RF2424 PCBA

UHF Quadrature Modulator

Fully Assembled Evaluation Board

Functional Block Diagram

RF Micro Devices, Inc.

7628 Thorndike Road

Greensboro, NC 27409, USA

Tel (336) 664 1233

Fax (336) 664 0454

http://www.rfmd.com

Rev A6 010817

5-43

RF2424

Absolute Maximum Ratings

Parameter

Supply Voltage

Input LO and RF Levels

Operating Ambient Temperature

Storage Temperature

Rating

5.5

+6.0

-40 to +85

-40 to +150

Unit

V

DC

dBm

°C

Caution!

ESD sensitive device.

RF Micro Devices believes the 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 responsibility for the use of the described product(s).

Parameter

Carrier Input

Frequency Range

Power Level

Input impedance

Specification

Min.

Typ.

Max.

700

-6

43 + j1.8

DC

1.6

V

REF

± 0.3

0.2

1

40

100

1000

+6

Unit

MHz

dBm

Ω

MHz

V

dB

°

kΩ

µA

Condition

T=25 °C, V

CC

=3V

5

MODULATORS AND

UPCONVERTERS

At 900MHz

Modulation Input

Frequency Range

Reference Voltage (V

REF

)

Maximum Modulation (I&Q)

Gain Asymmetry

Quadrature Phase Error

Input DC Resistance

Input Bias Current

RF Output

Output Power

Output Impedance

Broadband Noise Floor

Sideband Suppression

Carrier Suppression

IM

3

Suppression

+5.0

+7.5

50

-140

35

30

100

10

1.0

2.7

45

53

V

CC

1.2

5.5

55

10

dBm

Ω

dBm/Hz

dB

ns

kΩ

V

mA

µA

V

CC

=3V, LO power=-3dBm, LO

freq=900MHz, I/Q drive level=0.2V

P

, SSB

25

DSB output (+9dBm total power)

Power Down

Turn On/Off Time

PD Input Resistance

Power Down “ON”

Power Down “OFF”

Power Supply

Voltage

Current

Power Down

V

CC

=3V

V

CC

=5V

5-44

Rev A6 010817

RF2424

1

Function

I REF

Description

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 1.6V is recom-

mended. The SIG and REF 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

REF inputs in a balanced mode. If single ended operation is desired

then the input is applied to I SIG, pin 16. In that case, I REF and Q REF

are tied together and AC coupled to ground. To obtain a carrier sup-

pression of better than 40dB, I REF may be tuned ±20mV relative to

the I SIG. Without tuning, it will typically be better than 25dB.

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 1.6V is recom-

mended. The SIG and REF inputs are inputs of a differential amplifier.

Therefore the REF and SIG inputs are interchangeable. If swapping the

Q SIG and Q REF pins, the I SIG and I REF also need to be swapped

to maintain the correct phase. It is also possible to drive the SIG and

REF inputs in a balanced mode. If single ended operation is desired

then the input is applied to Q SIG, pin 15. In that case, Q REF and Q

REF are tied together and AC coupled to ground. To obtain a carrier

suppression of better than 40dB, Q REF may be tuned ±20mV relative

to the Q SIG. Without tuning, it will typically be better than 25dB.

Power supply for the I mixer, Q mixer and the RF Output amplifier.

MIXOUT: Combined output of the I mixer and Q mixer. By changing the

inductor value, maximum RF output is tuned to different frequency. If

the inductor value is changed, the RF output match needs to be

adjusted for 50Ω output impedance.

Ground connection for the LO and baseband amplifiers and mixers.

Same as pin 5.

The input of the phase shifting network.

LO

Interface Schematic

Q SIG

Q REF

BIAS

2

Q REF

Q SIG

Q REF

5

BIAS

3

4

VCC1

MIX OUT

5

6

7

8

9

GND1

LO IN

GND3

RF OUT

Ground connection for the LO phase shift network.

RF Output. An external LC matching network is needed for a 50Ω

match.

RF OUT

BIAS

10

11

12

GND2

GND1

PD

Ground connection for the RF output stage.

Same as pin 5.

Power Down control. When this pin is “low”, all circuits are shut off.

PD

13

14

15

16

VCC2

GND1

Q SIG

I SIG

Power supply for all circuits except mixers and output amplifier.

Same as pin 5.

Baseband input to the Q mixer. Maximum output power is obtained

when the input signal has a peak to peak amplitude of 400mV. The DC

level for this pin is 1.6V, same as QREF.

Baseband input to the Q mixer. Maximum output power is obtained

when the input signal has a peak to peak amplitude of 400mV. The DC

level for this pin is 1.6V, same as QREF.

See pin 2.

See pin 1.

Rev A6 010817

5-45

MODULATORS AND

RF2424

Application Schematic

V

REF

C

R

C

1

2

3

1 nF

L

4

1 nF

5

6

LO IN

7

8

-45°

+45°

16

POWER

CONTROL

C

15

14

13

Vcc

I SIG

Q SIG

Vcc

1 nF

5

MODULATORS AND

UPCONVERTERS

Σ

12

11

10

9

1 nF

PD

RF OUT

NOTE:

The values of R and C depend on the minimum baseband frequency (i.e., the cutoff

frequency of this high pass filter should be lower than the lowest frequency component

in the I/Q spectrum).

5-46

Rev A6 010817

RF2424

Evaluation Board Schematic

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

Drawing 2424400 Rev -

C10

100 pF

1

C8

33 nF

VCC

P1-1

C1

1 nF

C3

1 nF

L3

8.2 nH

2

3

4

5

6

7

8

-45°

+45°

R3

100

Ω

50

Ω µstrip

I SIG

J1

VREF

P2-1

16

POWER

CONTROL

50

Ω µstrip

15

14

13

C9

100 pF

R2

100

Ω

Q SIG

J2

VCC

P1-1

C7

1 nF

PD

P2-3

C6

1 nF

C4

4 pF

L2

6.8 nH

Σ

12

11

10

9

5

MODULATORS AND

LO IN

J3

50

Ω µstrip

L1

10 nH

50

Ω µstrip

RF OUT

J4

VCC

P1-1

P1

P1-1

1

2

3

VCC

GND

P2-3

P2-1

P2

1

2

3

VREF

GND

PD

C5

1 nF

Rev A6 010817

5-47

RF2424

RF2424 Overview

Preview

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