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TARGET DATA
February, 27 2003
LET9045S
RF POWER TRANSISTORS
Ldmos Enhanced Technology in Plastic Package
N-CHANNEL ENHANCEMENT-MODE LATERAL
MOSFETs
EXCELLENT THERMAL STABILITY
COMMON SOURCE CONFIGURATION
P
OUT
= 45 W with 17 dB gain MIN @ 945 MHz /
28V
NEW RF PLASTIC PACKAGE
HIGH GAIN
ESD PROTECTION
AVAILABLE IN TAPE & REEL with TR SUFFIX
DESCRIPTION
The LET9045S is a common source N-Channel,
enhancement-mode lateral Field-Effect RF power
transistor. It is designed for high gain, broad band
commercial and industrial applications. It operates
at 28 V in common source mode at frequencies up
to 1 GHz. LET9045S boasts the excellent gain,
linearity and reliability of ST's latest LDMOS
technology mounted in the first true SMD plastic
RF power package, PowerSO-10RF. LET9045S's
superior linearity performance makes it an ideal
solution for base station applications.
The PowerSO-10 plastic package, designed to
offer high reliability, is the first ST JEDEC
approved, high power SMD package. It has been
specially optimized for RF needs and offers
excellent RF performances and ease of assembly.
PowerSO-10RF
(straight lead)
ORDER CODE
LET9045S
BRANDING
LET9045S
ABSOLUTE MAXIMUM RATINGS (T
CASE
= 25
C)
Symbol
Parameter
Value
Unit
V
(BR)DSS
Drain-Source Voltage
65
V
V
GS
Gate-Source Voltage
-0.5 to +15
V
I
D
Drain Current
5
A
P
DISS
Power Dissipation
160
W
Tj
Max. Operating Junction Temperature
165
C
T
STG
Storage Temperature
-65 to +150
C
THERMAL DATA
R
th(j-c)
Junction -Case Thermal Resistance
0.85
C/W
Mounting recommendations are available in
www.st.com/rf/ (look for application note AN1294)
PIN CONNECTION
GATE
SOURCE
DRAIN
LET9045S
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ELECTRICAL SPECIFICATION (T
CASE
= 25
C)
STATIC
DYNAMIC
(
f = 945 MHz
)
DYNAMIC (
f = 925 - 960 MHz
)
ESD PROTECTION CHARACTERISTICS
MOISTURE SENSITIVITY LEVEL
Symbol
Test Conditions
Min.
Typ.
Max.
Unit
V
(BR)DSS
V
GS
= 0 V
I
DS
= 1 mA
65
V
I
DSS
V
GS
= 0 V
V
DS
= 28 V
1
A
I
GSS
V
GS
= 5 V
V
DS
= 0 V
1
A
V
GS(Q)
V
DS
= 28 V
I
D
= 250 mA
2.0
5.0
V
V
DS(ON)
V
GS
= 10 V
I
D
= 3 A
0.6
V
G
FS
V
DS
= 10 V
I
D
= 3 A
2.0
mho
C
ISS
V
GS
= 0 V
V
DS
= 28 V
f = 1 MHz
60
pF
C
OSS
V
GS
= 0 V
V
DS
= 28 V
f = 1 MHz
33
pF
C
RSS
V
GS
= 0 V
V
DS
= 28 V
f = 1 MHz
2.2
pF
Symbol
Test Conditions
Min.
Typ.
Max.
Unit
G
P
V
DD
= 28 V I
DQ
= 250 mA
P
OUT
= 45 W PEP
17
dB
D
V
DD
= 28 V I
DQ
= 250 mA
P
OUT
= 45 W PEP
44
%
IMD3
V
DD
= 28 V I
DQ
= 250 mA
P
OUT
= 45 W PEP
-28
dBc
P
1dB
V
DD
= 28 V I
DQ
= 250 mA
60
W
G
P
V
DD
= 28 V I
DQ
= 250 mA
P
OUT
= 45 W
17.8
dB
D
V
DD
= 28 V I
DQ
= 250 mA
P
OUT
= 45 W
59
%
Load
mismatch
V
DD
= 28 V I
DQ
= 250 mA
P
OUT
= 45 W
ALL PHASE ANGLES
10:1
VSWR
Symbol
Test Conditions
Min.
Typ.
Max.
Unit
P
1dB
V
DD
= 28 V I
DQ
= 250 mA
55
W
G
P
V
DD
= 28 V I
DQ
= 250 mA
P
OUT
= 45 W
17.2
dB
D
V
DD
= 28 V I
DQ
= 250 mA
P
OUT
= 45 W
55
%
Test Conditions
Class
Human Body Model
2
Machine Model
M3
Test Methodology
Rating
J-STD-020B
MSL 3
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LET9045S
Ouput Power Vs Drain Voltage
0
10
20
30
40
50
60
70
80
90
10
12
14
16
18
20
22
24
26
28
30
32
Vdd (V)
P
out
(
W
)
Idq = 250 mA
f = 945 MHz
Pin = 1.5 W
Pin = 1 W
Efficiency Vs Output Power
0
10
20
30
40
50
60
70
0
10
20
30
40
50
60
70
Pout (W)
Nd (%)
Vdd = 28 V
Idq = 250 mA
f = 945 MHz
Power Gain Vs
Output Power
1
10
100
1000
0
2
4
6
8
10 12
14 16 18 20 22
24 26 28 30
Vds (V)
C (
p
F
)
Coss
Ciss
Crss
f = 1 MHz
TYPICAL PERFORMANCE
Drain Current Vs Gate-Source Voltage
0.0
0.5
1.0
1.5
0
1
2
3
4
5
Vgs (V)
I
dq (
A
)
Vdd = 28 V
Power Gain Vs
Output Power
12
13
14
15
16
17
18
19
20
1
10
100
Pout (W)
Gp
(
d
B
)
Vdd = 28 V
f = 945 MHz
Idq = 100 mA
Idq = 250 mA
Idq = 100 mA
Idq = 600 mA
Idq = 400 mA
LET9045S
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Input Return Loss Vs Frequency
-20
-16
-12
-8
-4
0
910
920
930
940
950
960
970
f (MHz)
RL
(d
B
)
Vdd = 28 V
Idq = 250 mA
Pout = 50 W
TYPICAL PERFORMANCE
(BROADBAND)
Power Gain Vs Frequency
12
14
16
18
20
910
920
930
940
950
960
970
f (MHz)
Gp
(
d
B
)
Vdd = 28 V
Pout = 50 W
Idq = 250 mA
Efficiency Vs Frequency
40
45
50
55
60
65
70
75
80
910
920
930
940
950
960
970
f (MHz)
Nd
(%)
Vdd = 28 V
Idq = 250 mA
Pout = 50 W
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LET9045S
TEST CIRCUIT SCHEMATIC
TEST CIRCUIT COMPONENT PART LIST
COMPONENT
DESCRIPTION
C1, C8, C9, C13
47pF ATC 100B SURFACE MOUNT CERAMIC CHIP CAPACITOR
C2, C7
0.8-8.0pF GIGA TRIM VARIABLE CAPACITOR
C3, C4, C5, C6
7.5pF ATC 100B SURFACE MOUNT CERAMIC CHIP CAPACITOR
C10
1000pF ATC 100B SURFACE MOUNT CERAMIC CHIP CAPACITOR
C11, C15
0.1
F / 500V SURFACE MOUNT CERAMIC CHIP CAPACITOR
C12
10
F / 50V ALUMINUM ELECTROLYTIC RADIAL LEAD CAPACITOR
C14
100pF ATC 100B SURFACE MOUNT CERAMIC CHIP CAPACITOR
C16
220
F / 63V ALUMINUM ELECTROLYTIC RADIAL LEAD CAPACITOR
R1
18K
, 1W SURFACE MOUNT CHIP RESISTOR
R2
4.7M
, 1W SURFACE MOUNT CHIP RESISTOR
R3
120
, 2W SURFACE MOUNT CHIP RESISTOR
FB1, FB2
SHIELD BEAD SURFACE MOUNT EMI
L1, L2
INDUCTOR, 5TURNS AIR WOUND #22AWG, ID=0.059[1.49], NYLON COATED
MAGNET WIRE
+
G
V
RF
IN
V
D
RF
OUT
+
+
D
G
+
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