Conexant RF106 Datasheet

RF106 900 MHz Power Amplifier

Product Description

The RF106 is a class AB RF power amplifier for 900 MHz
ISM band applications. It delivers output power
proportional to the input signal power.

The RF106 power amplifier, combined with Conexant's
RF105 diSSTance™ (digital Spread Spectrum
Technology) transceiver, forms a complete system
solution for a direct conversion 900 MHz diSSTance radio
which is fully compliant with FCC Part 15 regulations in
the ISM band.

The RF106 is operational in the 900 MHz ISM band with
supply voltage ranging from 2.7V to 5V. It is available in a
small 20-pin TSSOP package, shown in Figure 1. Figure 2
shows a block diagram for the RF106.

RFOUT

GND1

MATCH

VCC1

NC

VCC2

NC

VCC3

GND2

ENABLE

1
2
3
4
5
6
7
8
9
10

RF106

Features

• Class AB-type RF power amplifier

• 100 mW peak envelope output power

• Very fast settling from standby mode to active

mode

• Efficient high output power operation

• Very few external components required

• 20-pin TSSOP package

Applications

• diSSTance-technology cordless telephone

•

Direct s

• Frequency hopping spread spectrum systems

• Wireless LANs

• Wireless modems

• Wireless security

• Inventory control

20
19
18
17
16
15
14
13
12
11

equence spread spectrum systems

systems

GND9
GND8
GND7
GND6
NC
NC
GND5
GND4
GND3
RFIN

Figure 1. RF106 Pin Signals – 20 Pin TSSOP

RFOUTRFIN

ENABLE

A1 A2 A3

Bias

Figure 2. RF106 Block Diagram

Data Sheet 2/1/99 Order No. W118

RF106 900 MHz Power Amplifier

Technical Description

The RF106 is a three stage, class AB RF power amplifier
for the 902-928 MHz ISM band. A class AB power
amplifier allows a wide range of output powers without
excessive idle power dissipation. Figure 3 shows a typical
application circuit for the RF106.

Recommendations on Layout and Implementation

Matching

An input matching network and an output matching
network are needed for maximum power transfer. For
greatest efficiency, it is recommended that the input
matching network be determined before the output
matching network. Matching network values are layout­sensitive. If the RF106 is used with Conexant's RF105
transceiver, the input matching network is not required if
the connecting traces are short.

A bypassing capacitor of 33pF and a decoupling capacitor
of 1nF for low frequency noise are recommended. Due to
layout variations the value of the capacitor may vary.

General Grounding Requirements

All ground pins should have minimum trace inductance to
ground. If a ground plane cannot be provided right at the
pins, the vias to ground plane should be placed as close
to the pins as possible. There should be one via for each
ground pin, unless otherwise specified. If the ground
plane is at the bottom layer, two vias per pin in parallel
may be required.

It is important to provide pins 13 and 14 with separate
low-impedance connections to GND, isolated from other
top-layer grounds.

NC pins are not used and should be connected to ac
ground, Vcc or ground, as shown in Figure 3.

Bypassing

All VCC pins should have proper bypassing. These
decoupling capacitors should be placed very close to the
pins, preferably right at the Vcc pins.

Vcc

33pF

Output
matching
network*

1.5nH

Rx

section

90°
phase
shifter

Matching
network*

33pF

470

ENABLE

10k

Vcc

Vcc

Vcc

1nF

LPF

33pF

Ω

Ω

10

1nF

10

1nF

10

1nF

33pF

Ω

33pF

Ω

33pF

22nH

ESD Sensitivity

The RF106 is a static-sensitive electronic device. Do not
operate or store near strong electrostatic fields. Take
proper Electrostatic Discharge (ESD) precautions.

1

2

3

4

5

RF106

6

7

8

9

10

20

19

18

17

16

15

14

13

12

11

33pF

* Matching network values are layout-dependent.

Input

matching

network*

RFIN

Figure 3. RF106 Typical Application Circuit

2

Conexant

W118

2/1/98