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Product Description
Ordering Information
Typical Applications
Features
Functional Block Diagram
RF Micro Devices, Inc.
7625 Thorndike Road
Greensboro, NC 27409, USA
Tel (336) 664 1233
Fax (336) 664 0454
http://www.rfmd.com
Optimum Technology Matching Applied
Si BJT
GaAs MESFET
GaAs HBT
Si Bi-CMOS
SiGe HBT
Si CMOS
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RF2
12
8P
1
2
3
4
8
7
6
5
VCC2
GND1
PD
RF IN
VCC1
RF OUT
RF OUT
GND 2
BIAS
CIRCUITS
PACKAGE BASE
GND
RF2128
MEDIUM POWER LINEAR AMPLIFIER
PCS Communication Systems
2.5GHz ISM Band Applications
Wireless LANs
Commercial and Consumer Systems
Portable Battery Powered Equipment
The RF2128 is a medium-power, high-efficiency, linear
amplifier IC. The device is manufactured on an advanced
Gallium Arsenide Heterojunction Bipolar Transistor (HBT)
process, and has been designed for use as the final RF
amplifier in 2.45 GHz ISM applications such as WLAN
and POS terminals. The part also will function as the final
stage in digital PCS phone transmitters requiring linear
amplification
operating
between
1900MHz
and
2200 MHz, with over 100 mW transmitted power, or as the
driver stage for the RF2125 high power amplifier. A sim-
ple power down function is included for TDD operation.
Single 3.0V to 6.5V Supply
100mW Linear Output Power
25dB Small Signal Gain
30% Efficiency
Digitally Controlled Power Down Mode
1900MHz to 2500MHz Operation
RF2128
Medium Power Linear Amplifier
RF2128 PCBA
Fully Assembled Evaluation Board
2
Rev A3 010112
.315
.305
.180 SQ MAX
.017
.013
.050
.006
.004
4MAX
0MIN
.017
.013
.057 MAX
.004
.000
1
.166
SQ
Metal lid and base, gold plated
Package Style: SOP-8-C
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Absolute Maximum Ratings
Parameter
Rating
Unit
Supply Voltage (V
CC
)
+7.5
V
DC
Power Down Voltage (V
PD
)
+5.5
V
DC Supply Current
125
mA
Input RF Power
+12
dBm
Output Load VSWR
20:1
Operating Case Temperature
-40 to +100
C
Operating Ambient Temperature
-40 to +85
C
Storage Temperature
-40 to +150
C
Parameter
Specification
Unit
Condition
Min.
Typ.
Max.
Overall
T = 25 C, V
CC
=5V, V
PD
= 5.0V,
Freq= 2400MHz
Frequency Range
1900 to 2500
MHz
Maximum Output Power
>+20
dBm
V
CC
= 5.0V, V
PD
= 5.0V, P
IN
=-3.0dBm
Maximum Output Power
>+23
dBm
V
CC
= 6.0V, V
PD
= 5.5V, P
IN
=0dBm
Total CW Efficiency
30
%
Maximum output
Small-signal Gain
25
dB
Second Harmonic
-25
dBc
Third Harmonic
-22
dBc
Isolation
15
dB
V
PD
= 0.2V
Input VSWR
2:1
Input Impedance
50
Noise Figure
7
dB
Two-tone Specification
Average Two-Tone Power
+17
dBm
PEP- 3dB
IM
3
-24
dBc
P
OUT
=+14dBm for each tone
IM
5
-36
dBc
P
OUT
=+14dBm for each tone
IM7
-44
dBc
P
OUT
=+14dBm for each tone
Two-Tone Power-Added
Efficiency
36
%
Power Down Control
Power Down "ON"
V
CC
V
Voltage supplied to the input; device is "on"
Power Down "OFF"
0
1.2
V
Voltage supplied to the input; device is "off"
Power Supply
Voltage
5
V
Specifications
3.0 to 6.5
V
Operating
Current
50
65
mA
Operating Idle
85
mA
At maximum output power
Current
10
A
Power Down
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).
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Application Schematic
2450MHz
Pin
Function
Description
Interface Schematic
1
VCC2
Power supply for the driver stage and interstage matching. External
matching on this pin is required to optimize the gain. The matching on
this port also greatly affects the input impedance. A decoupling capaci-
tor of 330pF is required, together with a series RC for tuning for maxi-
mum gain at the desired frequency. See the application information for
details.
2
GND1
Ground connection for the driver stage. Keep traces physically short
and connect immediately to the ground plane for best performance.
3
PD
Power Down control. When this pin is "low", all circuits are shut off. A
"low" is typical 1.2V or less at room temperature. When this pin is
"high", all circuits are operating normally. A "high" is V
CC
. If PD is below
V
CC
, output power and performance will be degraded. This could be
used to obtain some gain control, but results are not guaranteed.
4
RF IN
RF Input. This is a 50
input, but the actual impedance depends on the
matching provided on pin 1. An external DC blocking capacitor is
required if this port is connected to a DC path to ground.
5
GND2
Ground connection for the output stage. Keep traces physically short
and connect immediately to the ground plane for best performance.
6
RF OUT
RF Output and power supply for the output stage. Bias for the output
stage needs to be provided on this pin. This can be done through a
quarter-wave microstrip that is RF grounded on the other end. For
matching to 50
, an external series microstrip line is required.
7
RF OUT
Same as pin 6.
8
VCC1
Power supply for the bias circuits. An external RF bypass capacitor of
22pF is required. Keep the traces to the capacitor as short as possible,
and connect the capacitor immediately to the ground plane.
Pkg
Base
GND
Ground connection. The backside of the package should be connected
to the ground plane through a short path, i.e., vias under the device
may be required.
1
2
3
4
8
7
6
5
BIAS
CIRCUITS
PACKAGE BASE
1.5
2.4 pF
330 pF
22 pF
V
CC
RF IN
6.2 pF
22 pF
1 nF
15 pF
RF OUT
PCB materials: FR-4
Thickness: 0.031"
VPD
POWER
DOWN
33 pF
L= 175 mil,
W= 10mil
L= 250 mil,
W= 20 mil
L = 220 mil,
W = 25 mil
L = quarter wave,
W= 10mil
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RF2128
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RF2
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Evaluation Board Schematic
2450MHz Operation
(Download Bill of Materials from www.rfmd.com.)
Evaluation Board Layout
1.547" x 1.068"
1
2
3
4
8
7
6
5
BIAS
CIRCUITS
PACKAGE BASE
GND
C4
330 pF
C5
22 pF
C1
6.2 pF
C3
1 nF
C6
16 pF
C7
1
F
P1-1
C8
330 pF
C9
1 nF
P1-3
RF IN
J1
RF OUT
J2
P1-1
P1-3
P1
VPD
GND
VCC
1
2
3
2128400 Rev -
(PCB mat'l: FR-4,
Thickness: 0.031")
C2
2.4 pF
100
, L=174 mil,
W=10 mil
L=250 mil,
W=20 mil
L=217 mil, W=26 mil
50
strip
50
strip
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