Datasheet RF3330, RF3330PCBA Datasheet (RF Micro Devices)

Preliminary

RF3330

3

Typical Applications

• CATV Set-Top Boxes

• Cable Modems

Product Description

The RF3330 is a gain-controlled amplifier suitable for
application in the IF receive section of a cable tuner. It
consists of a high impedance differential input stage, a
low impedance differential output stage, and a differential
gain-controlled am plifier. The voltage gain may be varied
by applying an analog control voltage. The device is fabri­cated on an advanced Bi-CMOS process, and is housed
in an eight-lead SOT23 package.

IF GAIN CONTROLLED AMPLIFIER

• Cable-Ready TVs

1.59

1.61

TEXT*

2.80

3.00

2.60

3.00

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

3°MAX

0°MIN

0.365

0.650

1.44

1.04

0.15

0.05

0.127

3

AMPLIFIERS

LINEAR CATV

Optimum Technology Matching® Applied

Si BJT GaAs MESFETGaAs HBT
Si Bi-CMOS

ü

SiGe HBT

1VCC 8VCC

2GND

3VOUT

4VOUTB

Biasing &

AGC

Control

Si CMOS

7VIN

6VINB

5VAGC

Functional Block Diagram

0.35

0.55

Package Style: SOT23-8

Features

• Single 5V Positive Power Supply

• 26dB Gain Range

• 150MHz Bandwidth

• Compact Package

Ordering Information

RF3330 IF Gain Controlled Amplifier
RF3330 PCBA Fully Assembled Evaluation Board - 75Ω
RF3330 PCBA Fully Assembled Evaluation Board - 50Ω

RF Micro Devices, Inc.
7628 Thorndike Road
Greensboro,NC 27409, USA

Tel [phone]

Fax [phone]

http://www.rfmd.com

Rev A2 010820

3-1

RF3330

Absolute Maximum Ratings

Parameter Rating Unit

Supply Voltage 7 V
Operating Ambient Temperature -40 to +85 °C
Storage Temperature -60 to +150 °C

Preliminary

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).

3

Specification

Unit Condition

Typical performance is at TA=+25°C,
V

=5V.

CC

Overall

Parameter

Min. Typ. Max.

DC Specifications

SupplyVoltage 4.75 5.0 5.25 V
Supply Current 18 25 mA
AGC Control Voltage 0.5 3.3 V 0.5V=Minimum Gain

AMPLIFIERS

LINEAR CATV

AGC Input Impedance 10 MΩ

3.3V=Maximum Gain

AC Specifications

3dB Bandwidth 150 MHz
Voltage Gain

Maximum 33.0 34.0 dB V
Minimum 8.0 10.0 dB V

Maximum Input Level 50 dBmV(rms) While meeting distortion specification
Maximum Output Level 50 dBmV(rms) While mee ting distortion specification
Output 1dB Compression 66 dBmV(rms) Maximum Gain
Output Harmonic Distortion -44 -40 dBc Output level=50dBmV(rms); V

Input IP3, Maximum Gain 45 dBmV(rms) Output level=50dBmV(rms); V
Input IP3, Minimum Gain 60 dBmV(rms) Output level=50dBmV(rms); V
Input Noise, Maximum Gain 4.5 nV/rtHz

Input Noise, Minimum Gain 42 nV/rtHz
Output Impedance 10 Ω Differential
Input Impedance 2000 Ω Differential
Output Load Impedance 1 kΩ Differential
Output Load Capacitance 2 pF Differential

AGC
AGC

=3.3V
=0.5V

AGC
AGC
AGC

=3.3V
=3.3V
=0.5V

3-2

Rev A 2 010820

Preliminary

RF3330

Pin Function Description Interface Schematic

1VCC
2GND
3VOUT

Supply Voltage
Supply Ground
Output pin.

OUT
OUTB

3

4VOUTB

5VAGC

6VINB

7VIN

Complementary output pin.

AGC control voltage.

Complementary input pin. This should be externally AC-coupled to sig­nal source.

Input pin. This should be externally AC-coupled to signal source.

VAGC

VBIAS

VBIAS

OUT
OUTB

100 kΩ

1kΩ

IN

1kΩ

IN

10 kΩ

75

75

1kΩ

1kΩ

VREF

VBIAS
INB

VBIAS
INB

AMPLIFIERS

LINEAR CATV

8VCC

Rev A2 010820

Supply Voltage

3-3

RF3330

Preliminary

Pin Out

1VCC 8VCC

3

2GND

3VOUT

4VOUTB

7VIN

6VINB

5VAGC

Application Schematic

AMPLIFIERS

LINEAR CATV

V

CC

+

VOUT

VOUTB

VIN

VINB

VAGC

Biasing &

AGC

7

6

5

Control

Note orientation of board.

100 pF 3.3µF

18

2

3

4

3-4

Rev A 2 010820

Preliminary

Evaluation Board Schemati c

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

P1-1 VCC

P1-3 AGC

VCC

HEADER4

RF3330

P1

1

GND

2
3

GND

4

3

+

C3

3.3 µF

J2

VIN

(BAL)

J3

VIN

(BAL)

J1

VIN

(UNBAL)

AGC

NOTES:

1. C3, Tantulum Capacitor: Case Size Y, 6.3 V.

2. See Evaluation Test Procedure for more information.

3. Parts with * following the reference designator should not be populated on the evaluation board.

50 Ωµstrip

50 Ωµstrip

50 Ωµstrip

C2

100 nF

C7

100 nF

C8

100 nF

R6

5.1 kΩ

C9

100 pF

F1*

C6

33 nF

Biasing &

AGC

7

6

5

Control

Note orientation of board.

18

2

3

4

3330410-

C1

100 pF

R2

470 Ω

R4

470 Ω

R3

51 Ω

6
5
4

T1

TTWB

1010-1

R1*
DNI

R5*
DNI

C4*
DNI

1
2
3

C5*
DNI

50 Ωµstrip

50 Ωµstrip

J5

VOUT

(BAL)

J4

VOUT

(UNBAL)

AMPLIFIERS

LINEAR CATV

Rev A2 010820

3-5

3

RF3330

Preliminary

Evaluation Board Layout

Board Size 2.0” x 2.0”

Board Thickness 0.062”, Board Material FR-4

AMPLIFIERS

LINEAR CATV

3-6

Rev A 2 010820

Preliminary

RF3330

Evaluation Test Procedure

Introduction

The RF3330 is an IF amplifier with AGC, designed for
use in Cable Television applications. Voltage gain is
varied using an analog voltage control signal. The dif­ferential input is high impedance (2000Ω)andthedif­ferential output is low impedance (10Ω). The 3dB
bandwidth is 150MHz and has a maximum voltage
gain of 34dB and a minimum voltage gain of 8dB. The
AGC Control Voltage ranges from 0.5V for minimum
gain to 3.3V for maximum gain. The device is pack­aged in the SOT23-8, which minimizes board area.

Evaluation Board

The 3330410 board has been designed to achieve
maximum versatility for device evaluation. The board is
designed for either a differential or single-ended input
signal. Likewise, the output can be either singly or dif­ferentially loaded. There is also a separate V

CC

and

AGC voltage pin. For constant maximum gain applica­tions, the V

and AGC pins can be tied together.

CC

Input

For differential operation on the input, the J1 connector
(V

unbalanced) is not required. Differential voltages

IN

are applied directly through connectors J2 and J3 (V

IN

balanced). DC blocking capacitors are also provided to
protect equipment or upstream components. Boards

ordered from RF Micro Devices are assembled in this
configuration.

Single-ended operation on the input can be accom­plished in two ways. The first option uses the differen­tial board setup as described above, with the addition
of an external low frequency 180° power combiner.
The combiner splits the single input signal into two sig­nals with inverted phase. The s econd option for single­ended operation utilizes a SAW filter which c onverts
from double to single-ended. The current evaluation
board has an option to insert a SAW filter on the input.
For this setup, the J1 connector (V

unbalanced)

IN

would be utilized. The 3330410 board has been evalu­ated using a 44 MHz Siemens+ Matsushita filter. This is
acommonIFfrequencyusedincablemodemapplica­tions.

Table 1. SAW Filters

EPCOS P/N FC(MHz)

X6857D 36.000
X6966M 36.125
X6964D 43.750
X6855M 44.000
X6866D 44.000
X6965M 44.000

Output

For differential operation on the output, the optional
C4, C5, R1, and R5 would be inserted and the T1
transformer would be removed. The J4 (V

anced) and J5 (V

balanced) connectors would be

OUT

OUT

unbal-

uses as differential outputs.
For single-ended operation on the output, only the J4

connector (V

unbalanced) is used and only one

OUT

3

analyzer is necessary. There is a 1:1 transformer to
convert the unbalanced output to a balanced signal.
The amplifier is designed to drive a 1000Ω load. Driv­ing a 50 Ω load, presented by the spectrum analyzer
will cause the amplifier to saturate. In order to present

LINEAR CATV

a 1000Ω load to the amplifier a resistive matching cir­cuit is on the board. Boards ordered from RF Micro

Devicesare assembledin this configuration.

Test Setup Calibration

Because of the fact that the impedances of the ampli­fier are not 50Ω, there are some special considerations
when calibrating a test setup.The evaluation test setup
isshowninFigure1.

Input

As stated previously, the balanced input impedance of
the RF3330 is 2000 Ω. The signal generator used has
an unbalanced 50Ω source, and is typically used in
unbalanced 50Ω impedance systems. Due to this load
mismatch, a positive amplitude offset needs to be
applied to the signal generator. The formulas used to
calculate this offset are given below in Equations 1
through 3. It should be noted that the unbalanced
1000 Ω load is used, because all data in the datasheet
is referenced to single-ended operation. Using a spec­trum analyzer probe, the actual offset measured was

7.5 dB, and this is what is used for the amplitude offset
in the signal generator.

MismatchLoss (ML)=-10*log(1-|Γ

Γ

=(Z-Z0)/(Z+Z0)Eq.2

L

ML=-10* log(1- [(1000-50) /(1000+50)]

|2)Eq.1

L

2

)=7.4dB

Eq. 3

AMPLIFIERS

Rev A2 010820

3-7

RF3330

Preliminary

3

Output

On the output, the losses due to the resistive matching
pad must also be calibrated out of the setup. Because
of the 1:1 transformer, the spectrum analyzer appears
as a 50Ω resistorin parallelwith this circuit (see Figure

2). Equation 4 illustrates the calculation necessar y to
obtain the amount of loss due to this m atching circuit.
The balun also has an additional 0.5dB to 1.0 dB of

Frequency =

1MHzto
150 MHz

AMPLIFIERS

LINEAR CATV

Figure 1. RF3330 Test Setup

Signal Generator

R4

470 Ω

Frequency =

1MHzto
150 MHz

Mini-Circuits

ZMSCJ-2-1

Divider

RF3330

loss, which is added in to the overall output losses.
This was verified with a spectrum analyzer probe. The
offset used in the test setup is 32.5dB on the spectrum
analyzer.

Resistive Pad Loss=

20 *log(25/(470+25+470))=-31.7dB Eq. 4

Resistive

Match

3330410 Evaluation Board

Transformer

1:1

Frequency =

1MHzto
150 MHz

Spectrum Analyzer

R3

51 Ω

R2

470 Ω

Figure 2. Equivalent Output Circuit

50 Ω

3-8

Rev A 2 010820

RF3330

Preliminary

3

IIP3 versus Gain

V

=5.0V, F=50MHz

65.0

60.0

55.0

50.0

IIP3 (dBmV)

45.0

40.0

AMPLIFIERS

LINEAR CATV

35.0

5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0

65.0

60.0

CC

Gain (dB)

IIP3 versus V

GC

VCC=5.0V, F=50MHz

-40°C
+25°C
+85°C

-40°C
+25°C
+85°C

40.0

-40°C

35.0

30.0

25.0

20.0

Gain (dB)

15.0

10.0

5.0

0.5 1.0 1.5 2.0 2.5 3.0 3.5

+25°C
+85°C

Gain versus V

GC

VCC=5.0V, F=50MHz

VGC(V)

55.0

IIP3 (dBmV)

50.0

45.0

40.0

0.5 1.0 1.5 2.0 2.5 3.0 3.5

VGC(V)

3-9

Rev A 2 010820

3

RF3330

AMPLIFIERS

LINEAR CATV

Preliminary

3-10

Rev A 2 010820