STM961-15B
RF POWER MODULE
DIGITAL CELLULAR APPLICATIONS
s
LINEAR POWER AMPLIFIER
s
915-960 MHz
s
26 VOLTS
s
INPUT/OUTPUT 50 OHMS
s
POUT = 42 dBm CW or PEP
s
GAIN = 30 dB
DESCRIPTION
The STM961-15B module is designed for digital
cellular radio base station applications in the
915-960 MHz frequency range operating at 26V.
The STM961-15B is designed to meet the low
distortion, high linearity requirements of modern
digital cellular base station equipment.
PIN CONNECTION
June 1999
ABSOLUTE MAXIMUM RATINGS (T
case
= 85
o
C)
Symbol
Parameter
Valu e
Un it
V
S1,
V
S2
DC Supply Volt age
28
Vdc
V
B
DC Bias Voltage
28
Vdc
P
I N
RF Input Power
14
dBm CW
P
OUT
RF Output Power (V = 26V)
43
dBm CW
T
STG
Storage Temperature
- 30 t o + 100
o
C
CASE STYLE H110
®
ORDER CODE
BRANDING
STM961-15B
STM961-15B
1. RF Input
3.V
B
, 26V
2. V
S1,
26V
4. RF Output
1/7
ELECTRICAL SPECIFICATION (T
case
= -10
o
C to +85
o
C, V
S1
= 26 V, V
B
= 26 V to 27 V)
DYNAMIC
Symb ol
Parameter
T est Con ditio ns
Mi n.
Typ .
Max.
Un it
BW
Frequency Range
915
960
MHz
G
P
Power G ain
P
OUT
= +42 dBm CW
28
30
dB
h
Ef ficiency
P
OUT
= +42 dBm CW
32
35
%
VSWR
P
OUT
= +42 dBm CW
Z
S
, Z
L
= 50
2:1
VSW R
I
Q
Quiescent Current
P
IN
= 0 dBm
580
mA
2F
O
Harmonics
P
OUT
= +42 dBm CW
-30
dBc
3F
O
Harmonics
P
OUT
= +42 dBm CW
-50
dBc
F
Gain F lat ness
P
OUT
= +42 dBm CW
1
dB
P
1 dB
Output Power @ 1
dB Compression
41
dBm
Load Mismat ch
VSW R = 3:1
P
OUT
= +42 dBm CW
No Degradation in Output
Power
St ability
P
OUT
= +10 dBm to +42 dBm
Load VSW R = 3:1
All phase angles
All Spurious O utputs more
t han 60db Below Carrier
MODULE DC AND TEST FIXTURE CONFIGURATION
REF. 1017332I
REF. 1014532D
STM961-15B
2/7
Power Gain vs Output Power
OUTPUT POWER [dBm]
POWER
GAIN
[dB]
10
20
30
34 36 38 40 42
29
30
31
32
33
34
f=960 MHz
Tcase= +85 deg.C
Tcase= +25 deg.C
Tcase = -10 deg.C
27.0 v
27.0 v
26. 0 v
25. 0 v
25. 0 v
27. 0 v
26. 0 v
25.0 v
26.0 v
Power Gain vs Frequency & Temperature
3rd Order IMD vs Output Power & Temperature
PEP [dBm]
3rd
IMD
[dBT]
20
22
24
26
28
30
32
34
36
38
40
42
-26.5
-31.5
-36.5
-41.5
-46.5
Freq.=915 MHz
Vs=26.0 V
Tcase=+85 deg.C
Tcase=+25 deg.C
Tcase=-10 deg.C
Power Gain vs Output Power
OUTPUT POWER [dBm]
POWER
GAIN
[dB]
10
20
30
34 36 38 40 42
29.5
30.5
31.5
32.5
33.5
34.5
f=915 MHz
Tcase =+85 deg.C
Tca se=+25 deg.C
Tcase=-10 deg.C
27.0 v
27.0 v
26.0 v
26.0 v
25.0 v
25.0 v
27.0 v
26.0 v
25.0 v
3rd Order IMD vs Output Power & Temperature
PEP [dBm]
3rd
IMD
[dBT]
20
22
24
26
28
30
32
34
36
38
40
42
-25
-30
-35
-40
-45
-50
Freq.=960 MHz
Vs=26.0 V
Tcase=+85 deg.C
Tcase=+25 deg.C
Tcase=-10 deg.C
5th Order IMD vs Output Power & Temperature
PEP [dBm]
3rd
IMD
[dBT]
20
22
24
26
28
30
32
34
36
38
40
42
-33
-38
-43
-48
-53
-58
Freq.=960 MHz
Vs=26.0 V
Tcase=+85 deg.C
Tcase=+25 deg.C
Tcase=-10 deg.C
FREQUENCY [MHz]
POWER
GAIN
[dB]
900
910
920
930
940
950
960
970
980
29
30
31
32
33
34
Po=42 dBm CW
Vs=26.0 V
Tc=-10 deg.C
Tc=+25 deg .C
Tc=+85 deg .C
TYPICAL PERFORMANCE
see note 1
see note 1
see note 1
STM961-15B
3/7
OUTPUT POWER [dBm]
CW
EFFICIENCY
[%]
32
34
36
38
40
42
7
12
17
22
27
32
37
Freq.=960 MHz
Vs=26.0 V
Tcase=+85 deg.C
Tcase=+25 deg.C
Tcase=-10 deg.C
5th Order IMD vs Output Power & Temperature
PEP [dBm]
3rd
IMD
[dBT]
20
22
24
26
28
30
32
34
36
38
40
42
-33
-38
-43
-48
-53
-58
Freq.=915 MHz
Vs=26.0 V
Tcase=+85 deg.C
Tcase=+25 deg.C
Tcase=-10 deg.C
Efficiency vs Frequency
FREQUENCY [MHz]
EFFICIENCY
[%]
900
910
920
930
940
950
960
970
980
34.5
35.5
36.5
37.5
38.5
Vs=25.0 V
Vs=26.0 V
Vs=27.0 V
Tcase=+25 deg.C
Po=42 dBm CW
CW Efficiency vs Output Power & Temperature
CW Efficiency vs Output Power & Temperature
OUTPUT POWER [dBm]
CW
EFFICIENCY
[%]
32
34
36
38
40
42
7
12
17
22
27
32
37
Freq.=915 MHz
Vs=26.0 V
Tcase=+85 deg.C
Tcase=+25 deg.C
Tcase=-10 deg.C
VSWR vs Frequency & Temperature
FREQUENCY [MHz]
VSWR
900
910
920
930
940
950
960
970
980
1
1.2
1.4
1.6
1.8
2
Vs=26.0 V
Po=42 dBm CW
Tcase=+85 deg.C
Tcase=+25 deg.C
Tcase=-10 deg.C
Note (1) :
Two-tone test; 20KHz separation;
IMD (in dBT) is referenced to the individual tone level.
TYPICAL PERFORMANCE
see note 1
STM961-15B
4/7
APPLICATIONS RECOMMENDATIONS
OPERATION LIMITS
The STM961-15B power module should never
be operated under any condition which exceeds
the Absolute Maximum Ratings presented on
this data sheet. Nor should the module be
operated continuously at any of the specified
maximum ratings. If the module is to be
subjected to one or more of the maximum rating
conditions, care must be taken to monitor other
parameters which may be affected.
DECOUPLING
Failure to properly decouple any of the voltage
supply pins will result in oscillations at certain
operating
frequencies.
Therefore,
it
is
recommended that these pins be bypassed as
indicated in the Module DC and Test Fixture
Configuration drawing of this data sheet.
MODULE MOUNTING
To insure adequate thermal transfer from the
module to the heatsink, it is recommended that
a satisfactory thermal compound such as Dow
Corning 340, Wakefield 120-2 or equivalent be
applied between the module flange and the
heatsink.
The heatsink mounting surface under the
module should be flat to within
±
0.05mm (
±
0.002 inch). The module should be mounted to
the heatsink using 3.5 mm (or 6-32) or
equivalent screws torqued to 5-6 kg-cm (4-6
in-lb).
The module leads should be attached to
equipment PC
board using 180
°
C
solder
applied to the leads with a properly grounded
soldering iron tip, not to exceed 195
°
C, applied
a minimum of 2 mm (0.080 inch) from the body
of the module for a duration not to exceed 15
seconds per lead. It is imperative that no other
portion of the module, other than the leads, be
subjected to temperatures in excess of 100
°
C
(maximum storage temperature), for any period
of time, as the plastic moulded cover, internal
components and sealing adhesives may be
adversely affected by such conditions.
Due
to
the
construction
techniques
and
materials used
within
the
module, reflow
soldering of the flange heatsink or leads, is not
recommended.
THERMAL CONSIDERATIONS
It will be necessary to provide a suitable
heatsink in order to maintain the module flange
temperature at or below to maximum case
operating temperature. In a case where the
module output power limited to +42 dBm CW
and designing for the worst case efficiency of
32%, the power dissipated by the module will
be 33.6 Watts. The heatsink must be designed
such that the thermal rise will be less than the
difference between the maximum operating
case
temperature
of
the
module
while
dissipating 33.6 W.
At T
case
= +85
o
C, V = 26V, Z
L
= 50
and P
OUT
= 42 dBm, maximum junction temperatures for
the individual transistors should be below the
following values:
Q1 = 140
o
C, Q2 = 145
o
C, Q3 = 130
o
C.
STM961-15B
5/7
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