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Product Description
Ordering Information
Typical Applications
Features
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
Optimum Technology Matching Applied
Si BJT
GaAs MESFET
GaAs HBT
Si Bi-CMOS
SiGe HBT
Si CMOS
2
3
4
5
13
12
11
10
VCC3
VCC1
GND
PD
RF OUT
GND
RF OUT
RF OUT
6
7
8
9
1
14
15
16
RF
I
N
GN
D
NC
NC
VCC2
NC
NC
RF
O
U
T
BIAS
CIRCUIT
RF2105L
HIGH POWER LINEAR UHF AMPLIFIER
900 MHz ISM Band Applications
400 MHz Industrial Radios
Digital Communication Systems
Driver Stage for Higher Power Applications
Commercial and Consumer Systems
Portable Battery-Powered Equipment
The RF2105L is a high 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 digital cellular phone transmitters or ISM
applications requiring linear amplification. It is packaged
in a 16-lead ceramic package with a backside ground.
The device is self-contained with the exception of the out-
put matching network and power supply feed line.
Single 2.7V to 6.5V Supply
Up to 1.2W CW Output Power
33dB Small Signal Gain
48% Efficiency
Digitally Controlled Power Down Mode
Small Package Outline (0.25" x 0.25")
RF2105L
High Power Linear UHF Amplifier
RF2105L PCBA
Fully Assembled Evaluation Board
2
Rev B3 010720
0.150
0.050
0.033
0.017
0.025
1
R0.008
0.050
0.075
0.065
0.080
0.080
0.258
0.242
0.258
0.242
0.022
0.018
0.208
0.192
sq.
Package Style: QLCC-16 Alumina
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Absolute Maximum Ratings
Parameter
Rating
Unit
Supply Voltage (V
CC
)
-0.5 to +8.5
V
DC
Power Down Voltage (V
PD
)
-0.5 to +6.5
V
DC
DC Supply Current
700
mA
Input RF Power
+12
dBm
Output Load
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
= 5.8V, V
PD
= 5.8V, Z
LOAD
=9
,
P
IN
=0dBm, Freq= 840MHz
Frequency Range
430 to 930
MHz
Maximum CW Output Power
+30.8
dBm
V
CC
= 5.8V, V
PD
= 5.8V, Z
LOAD
= 9
Note that increasing V
CC
above 5.8V does
not result in higher output power; power may
actually decrease.
+29.3
dBm
V
CC
= 5.0V, V
PD
= 5.0V, Z
LOAD
= 9
+28.5
dBm
V
CC
= 4.4V, V
PD
= 4.4V, Z
LOAD
= 9
+30
dBm
V
CC
= 5.8V, V
PD
= 5.8V, Z
LOAD
= 12
+27.8
dBm
V
CC
= 5.0V, V
PD
= 5.0V, Z
LOAD
= 12
+27
dBm
V
CC
= 4.4V, V
PD
= 4.4V, Z
LOAD
= 12
CW Efficiency at Max Output
48
%
DC Current at Max Output
450
mA
Small-signal Gain
33
dB
Second Harmonic
-23
dBc
Without external second harmonic trap
Third Harmonic
-36
dBc
Fourth Harmonic
-35
dBc
Input VSWR
<2:1
With external matching network; see appli-
cation schematic
Input Impedance
50
With external matching network; see appli-
cation schematic
Two-Tone Specification
Average Two-Tone Power
+27.0
dBm
PEP- 3dB
IM
3
-30
-25
dBc
P
OUT
=+24.0dBm/tone
IM
5
-32
-30
dBc
P
OUT
=+24.0dBm/tone
IM
7
-40
dBc
P
OUT
=+24.0dBm/tone
Two-Tone Current Drain
225
260
350
mA
Two-Tone Power-Added Eff.
33
%
Power Control
Power Down "ON"
V
CC
V
Voltage supplied to the input
Power Down "OFF"
0
V
Voltage supplied to the input
PD Input Current
3.7
5.0
mA
Only in "ON" state
Power Supply
Power Supply Voltage
2.7 to 6.5
V
DC
Total Idle Current Drain
2
10
A
V
PD
< 0.1V
DC
, V
CC
= 6.5V
60
mA
V
PD
= 4.4V
DC
, V
CC
=6.5V
80
mA
V
PD
= 5.0V
DC
, V
CC
=6.5V
80
100
165
mA
V
PD
= 5.8V
DC
, V
CC
=6.5V
120
mA
V
PD
= 6.5V
DC
, V
CC
=6.5V
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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Pin
Function
Description
Interface Schematic
1
VCC2
Positive supply for the second stage (driver) amplifier. This is an
unmatched transistor collector output. This pin should see an inductive
path to AC ground (V
CC
with a UHF bypassing capacitor). This induc-
tance can be achieved with a short, thin microstrip line or with a low
value chip inductor (~2.7nH). At lower frequencies, the inductance
value should be larger (longer microstrip line) and V
CC
should be
bypassed with a larger bypass capacitor (see the application schematic
for 430MHz operation). This inductance forms a matching network with
the internal series capacitor between the second and third stages, set-
ting the amplifier's frequency of maximum gain. An additional 1
F
bypass capacitor in parallel with the UHF bypass capacitor is also rec-
ommended, but placement of this component is not as critical. In most
applications, pins 1, 2, and 3 can share a single 1
F bypass capacitor.
2
VCC3
Positive supply for the active bias circuits. This pin can be externally
combined with pin 3 (VCC1) and the pair bypassed with a single UHF
capacitor, placed as close as possible to the package. Additional
bypassing of 1
F is also recommended, but proximity to the package is
not as critical. In most applications, pins 1, 2, and 3 can share a single
1
F bypass capacitor.
3
VCC1
Positive supply for the first stage (input) amplifier. This pin can be exter-
nally combined with pin 2 (VCC3) and the pair bypassed with a single
UHF capacitor, placed as close as possible to the package. Additional
bypassing of 1
F is also recommended, but proximity to the package is
not as critical. In most applications, pins 1, 2, and 3 can share a single
1
F bypass capacitor.
4
GND
Ground connection. For best performance, keep traces physically short
and connect immediately to ground plane. In addition, for specified per-
formance, the package's backside metal should be soldered to ground
plane.
5
PD
Power down control voltage. When this pin is at 0V, the device will be in
power down mode, dissipating minimum DC power. When this pin is at
V
CC
(3V to 6.5V), the device will be in full power mode delivering maxi-
mum available gain and output power capability. This pin may also be
used to perform some degree of gain control or power control when set
to voltages between 0V and V
CC
. It is not optimized for this function so
the transfer function is not linear over a wide range as with other
devices specifically designed for analog gain control; however, it may
be usable for coarse adjustment or in some closed loop AGC systems.
This pin should not, in any circumstance, be higher in voltage than V
CC
,
nor should it ever be higher than 6.5V. This pin should also have an
external UHF bypassing capacitor.
6
RF IN
Amplifier RF input. This is a 50
RF input port to the amplifier. It does
not contain internal DC-blocking and therefore should be externally
DC-blocked before connecting to any device which has DC present or
which contains a DC path to ground. A series UHF capacitor is recom-
mended for the DC-blocking.
7
GND
Same as pin 4.
8
NC
Not internally connected.
9
NC
Not internally connected.
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Pin
Function
Description
Interface Schematic
10
RF OUT
Amplifier RF output. This is an unmatched collector output of the final
amplifier transistor. It is internally connected to pins 10, 11, 13, and 14
to provide low series inductance and flexibility in output matching. Bias
for the final power amplifier output transistor must also be provided
through two of these four pins. Typically, pins 10 and 11 are connected
to a network that creates a second harmonic trap. For 830MHz opera-
tion, this network is simply a single 2.4pF capacitor from both pins to
ground. This capacitor series resonates with internal bond wires at two
times the operating frequency, effectively shorting out the second har-
monic. Shorting out this harmonic serves to increase the amplifier's
maximum output power and efficiency, as well as to lower the level of
the second harmonic output. Typically, pins 13 and 14 are externally
connected very close to the package and used as the RF output with a
matching network that presents the optimum load impedance to the PA
for maximum power and efficiency, as well as providing DC-blocking at
the output. An additional network of a bias inductor and parallel resistor
provides DC bias and helps to protect the output from high voltage
swings due to severe load mismatches. Shunt protection diodes are
included to clip peak voltage excursions above ~15V to prevent voltage
breakdown in worst case conditions.
11
RF OUT
Same as pin 10.
12
GND
Same as pin 4.
13
RF OUT
Same as pin 10.
14
RF OUT
Same as pin 10.
15
NC
Not internally connected.
16
NC
Not internally connected.
Pkg
Base
GND
This contact is the main ground contact for the entire device. Care
should be taken to ensure that this contact is well soldered in order to
prevent performance from being degraded from that indicated in the
specifications.
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