INTEGRATED CIRCUITS
SA5205A
Wide-band high-frequency amplifier
Product specification
Replaces data of February 24, 1992
1997 Nov 07
IC17 Data Handbook
Philip s Se m ic ond uc tors
Philips Semiconductors
Product specification
Wide-band high-frequency amplifier
SA5205A
EQUIVALENT SCHEMATIC
V
CC
R1
R2
Q3
V
OUT
Q6
Q2
R3
V
Q1
Q4
IN
RE2
RF1
RE1
Q5
RF2
SR00216
Figure 2. Equivalent Schematic
ABSOLUTE MAXIMUM RATINGS
SYMBOL
PARAMETER
RATING
UNIT
V
Supply voltage
9
5
V
CC
V
AC
AC input voltage
V
P-P
T
A
Operating ambient temperature range
SA grade
-40 to +85
780
°C
P
DMAX
Maximum power dissipation,
1, 2
T =25°C (still-air)
A
D package
mW
NOTES:
1. Derate above 25°C, at the following rates:
D package at 6.2mW/°C
2. See “Power Dissipation Considerations” section.
3
1997 Nov 07
Philips Semiconductors
Product specification
Wide-band high-frequency amplifier
SA5205A
DC ELECTRICAL CHARACTERISTICS
V
CC
=6V, Z =Z =Z =50Ω and T =25°C in all packages, unless otherwise specified.
S
L
O
A
SA5205A
Typ
SYMBOL
PARAMETER
TEST CONDITIONS
UNIT
Max
Min
5
5
8
8
V
V
V
Operating supply voltage range
CC
Over temperature
Over temperature
20
19
25
25
32
33
mA
mA
I
Supply current
Insertion gain
CC
S21
f=100MHz
17
19
21
dB
Over temperature
16.5
21.5
f=100MHz
25
S11
Input return loss
Output return loss
Isolation
dB
dB
dB
DC - f
12
12
MAX
f=100MHz
DC - f
27
S22
S12
MAX
f=100MHz
DC - f
-25
-18
MAX
t
t
Rise time
500
500
450
ps
ps
R
Propagation delay
Bandwidth
P
BW
±0.5dB
-3dB
MHz
MHz
dB
f
Bandwidth
550
MAX
Noise figure (75Ω)
Noise figure (50Ω)
Saturated output power
1dB gain compression
f=100MHz
f=100MHz
f=100MHz
f=100MHz
4.8
6.0
dB
+7.0
+4.0
dBm
dBm
Third-order intermodulation
intercept (output)
f=100MHz
f=100MHz
+17
+24
dBm
dBm
Second-order intermodulation
intercept (output)
4
1997 Nov 07
Philips Semiconductors
Product specification
Wide-band high-frequency amplifier
SA5205A
11
10
9
8
7
6
5
4
3
2
1
0
–1
–2
–3
–4
–5
–6
35
34
32
30
o
= 25 C
T
A
28
26
V
V
= 7V
= 6V
CC
CC
24
22
20
V
8
= 8V
CC
V
= 5V
CC
Z
= 50Ω
18
16
O
A
o
T
= 25 C
5
5.5
6
6.5
7
7.5
8
1
2
4
6
2
2
4
6
8
3
10
10
10
SR00218
SUPPLY VOLTAGE—V
SR00217
FREQUENCY—MHz
Figure 3. Supply Current vs Supply Voltage
Figure 7. Saturated Output Power vs Frequency
10
9
8
7
6
5
4
3
2
9
V
8V
CC =
Z
T
= 50Ω
= 25 C
O
A
V
6V
8
7
6
5
CC =
o
v
= 8v
cc
cc
cc
v
v
= 7v
= 6v
V
7V
V
5V
CC =
CC =
1
0
–1
v
= 5v
cc
–2
Z
= 50Ω
= 25 C
O
–3
–4
–5
–6
o
T
A
1
2
4
6
8
2
2
4
6
8
3
1
2
4
6
8
2
2
4
6
8
3
10
10
10
10
10
FREQUENCY—MHz
10
SR00220
FREQUENCY—MHz
SR00219
Figure 4. Noise Figure vs Frequency
Figure 8. 1dB Gain Compression vs Frequency
25
40
v
= 8v
cc
= 7v
35
30
25
v
cc
20
15
v
2
= 6v
cc
Z
= 50Ω
= 25 C
20
15
10
v
= 5v
O
cc
o
T
A
Z
T
= 50Ω
= 25 C
O
A
o
10
1
2
4
6
8
2
4
6
8
3
4
5
6
7
8
9
10
10
10
10
SR00221
POWER SUPPLY VOLTAGE—V
FREQUENCY—MHz
SR00222
Figure 5. Insertion Gain vs Frequency (S
)
Figure 9. Second-Order Output Intercept vs Supply Voltage
21
30
25
o
T
= 55 C
o
= 25 C
A
25
20
T
A
20
15
o
T
= 85 C
A
T
Z
= 50Ω
= 25 C
O
15
10
o
o
= 125 C
T
A
A
V
= 8V
CC
Z
= 50Ω
O
10
5
1
2
4
6
8
2
2
4
6
8
3
4
5
6
7
8
9
10
10
10
FREQUENCY—MHz
10
POWER SUPPLY VOLTAGE—V
SR00223
SR00224
Figure 6. Insertion Gain vs Frequency (S
)
Figure 10. Third-Order Intercept vs Supply Voltage
21
5
1997 Nov 07
Philips Semiconductors
Product specification
Wide-band high-frequency amplifier
SA5205A
2.0
10
1.9
o
T
= 25 C
= 6V
1.8
1.7
1.6
1.5
1.4
1.3
1.2
1.1
1.0
A
CC
–15
V
.
V
= 6V
CC
–20
–25
Z
T
= 50Ω
O
o
= 25 C
A
Z
Z
= 75Ω
O
O
= 50Ω
–30
1
2
4
8
2
2
4
6
8
3
10
10
10
6
1
2
3
8 10
10
2
4
6
8 10
2
4
6
FREQUENCY—MHz
FREQUENCY—MHz
SR00225
SR00226
Figure 11. Input VSWR vs Frequency
Figure 14. Isolation vs Frequency (S
)
12
2.0
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
1.1
1.0
25
20
v
= 8v
cc
= 7v
o
v
T
= 25 C
= 6V
cc
amb
CC
V
v
= 6v
cc
v
= 5v
15
10
cc
Z
Z
= 75Ω
= 50Ω
2
O
O
Z
T
= 75Ω
= 25 C
O
A
o
1
2
4
6
8
2
2
4
6
8
3
1
2
3
10
10
FREQUENCY—MHz
10
10
4
6
8 10
2
4
6
8 10
FREQUENCY—MHz
SR00227
SR00228
Figure 12. Output VSWR vs Frequency
Figure 15. Insertion Gain vs Frequency (S
)
21
40
35
25
o
T
= –55 C
o
A
T
= 25 C
A
30
20
15
10
OUTPUT
25
20
o
T
= 85 C
A
o
T
= 125 C
V
Z
= 6V
A
CC
O
= 50Ω
INPUT
2
o
Z
= 75Ω
T
= 25 C
O
A
15
10
V
= 6V
CC
1
2
4
6
8
2
4
6
8
3
1
2
4
6
8
2
2
4
6
8
3
10
10
10
10
10
FREQUENCY—MHz
10
FREQUENCY—MHz
SR00229
SR00230
Figure 13. Input (S ) and Output (S ) Return Loss vs
Figure 16. Insertion Gain vs Frequency (S
)
11
22
21
Frequency
6
1997 Nov 07
Philips Semiconductors
Product specification
Wide-band high-frequency amplifier
SA5205A
where R =12Ω, V =0.8V, I =5mA and I =7mA (currents rated
THEORY OF OPERATION
E1
BE
C1
C3
at V =6V).
CC
The design is based on the use of multiple feedback loops to
provide wide-band gain together with good noise figure and terminal
impedance matches. Referring to the circuit schematic in Figure 17,
the gain is set primarily by the equation:
Under the above conditions, V is approximately equal to 1V.
IN
Level shifting is achieved by emitter-follower Q and diode Q which
3
4
provide shunt feedback to the emitter of Q via R . The use of an
1
F1
ǒR
Ǔ
emitter-follower buffer in this feedback loop essentially eliminates
problems of shunt feedback loading on the output. The value of
) RE1
VOUT
VIN
F1
(1)
+
RE1
R
=140Ω is chosen to give the desired nominal gain. The DC
F1
which is series-shunt feedback. There is also shunt-series feedback
due to R and R which aids in producing wideband terminal
output voltage V
can be determined by:
OUT
F2
E2
impedances without the need for low value input shunting resistors
that would degrade the noise figure. For optimum noise
V =V -(I +I )R2,(4)
OUT CC C2 C6
performance, R and the base resistance of Q are kept as low as
E1
1
possible while R is maximized.
where V =6V, R =225Ω, I =8mA and I =5mA.
F2
CC
2
C2
C6
The noise figure is given by the following equation:
NF =
From here it can be seen that the output voltage is approximately
3.1V to give relatively equal positive and negative output swings.
Diode Q is included for bias purposes to allow direct coupling of
5
R
to the base of Q . The dual feedback loops stabilize the DC
KT
2qlC1
F2
1
rb ) RE1
)
ȡ
ȣ
ȴ
Ȥ
ȱ
ȳ
operating point of the amplifier.
(2)
10 log 1 )
dB
ȧ ȧ
ȧȧ
RO
The output stage is a Darlington pair (Q and Q ) which increases
the DC bias voltage on the input stage (Q ) to a more desirable
value, and also increases the feedback loop gain. Resistor R
optimizes the output VSWR (Voltage Standing Wave Ratio).
Inductors L and L are bondwire and lead inductances which are
6
2
Ȳ
Ȣ
1
0
where I =5.5mA, R =12Ω, r =130Ω, KT/q=26mV at 25°C and
C1
E1
b
R =50 for a 50Ω system and 75 for a 75Ω system.
0
1
2
The DC input voltage level V can be determined by the equation:
roughly 3nH. These improve the high-frequency impedance
matches at input and output by partially resonating with 0.5pF of pad
and package capacitance.
IN
V
IN
=V +(I +I ) R
BE1 C1 C3 E1
V
CC
R2
225
R1
650
L2
R0
10
V
Q3
OUT
3nH
Q6
Q2
L2
V
IN
Q4
Q1
R3
140
3nH
RF1
140
RE2
12
RE1
12
Q5
RF2
200
SR00231
Figure 17. Schematic Diagram
7
1997 Nov 07
Philips Semiconductors
Product specification
Wide-band high-frequency amplifier
SA5205A
output pins of the device. This circuit is shown in Figure 18. Follow
these recommendations to get the best frequency response and
noise immunity. The board design is as important as the integrated
circuit design itself.
POWER DISSIPATION CONSIDERATIONS
Whenusing the part at elevated temperature, the engineer should con-
sider the power dissipation capabilities.
At the nominal supply voltage of 6V, the typical supply current is
25mA (32mA Max). For operation at supply voltages other than 6V,
see Figure 3 for I versus V curves. The supply current is
CC
CC
SCATTERING PARAMETERS
inversely proportional to temperature and varies no more than 1mA
between 25°C and either temperature extreme. The change is 0.1%
per over the range.
The primary specifications for the SA5205A are listed as
S-parameters. S-parameters are measurements of incident and
reflected currents and voltages between the source, amplifier and
load as well as transmission losses. The parameters for a two-port
network are defined in Figure 19.
The recommended operating temperature ranges are air-mount
specifications. Better heat sinking benefits can be realized by
mounting the D package body against the PC board plane.
Actual S-parameter measurements using an HP network analyzer
(model 8505A) and an HP S-parameter tester (models 8503A/B) are
shown in Figure 20.
PC BOARD MOUNTING
Values for the figures below are measured and specified in the data
sheet to ease adaptation and comparison of the SA5205A to other
high-frequency amplifiers.
In order to realize satisfactory mounting of the SA5205A to a PC
board, certain techniques need to be utilized. The board must be
double-sided with copper and all pins must be soldered to their
respective areas (i.e., all GND and V pins on the SO package).
CC
The power supply should be decoupled with a capacitor as close to
V
CC
the V pins as possible and an RF choke should be inserted
CC
between the supply and the device. Caution should be exercised in
the connection of input and output pins. Standard microstrip should
be observed wherever possible. There should be no solder bumps
or burrs or any obstructions in the signal path to cause launching
problems. The path should be as straight as possible and lead
lengths as short as possible from the part to the cable connection.
Another important consideration is that the input and output should
RF CHOKE
DECOUPLING
CAPACITOR
5205A
V
V
IN
OUT
AC
AC
be AC coupled. This is because at V =6V, the input is
CC
COUPLING
CAPACITOR
COUPLING
CAPACITOR
approximately at 1V while the output is at 3.1V. The output must be
decoupled into a low impedance system or the DC bias on the
output of the amplifier will be loaded down causing loss of output
power. The easiest way to decouple the entire amplifier is by
soldering a high frequency chip capacitor directly to the input and
SR00232
Figure 18. Circuit Schematic for Coupling and Power Supply
Decoupling
POWER REFLECTED
FROM INPUT PORT
S
— INPUT RETURN LOSS
S
=
11
11
POWER AVAILABLE FROM
GENERATOR AT INPUT PORT
S
21
REVERSE TRANSDUCER
POWER GAIN
S
=
S
S
— REVERSE TRANSMISSION LOSS
OSOLATION
12
12
21
22
S
S
22
11
S
=
TRANSDUCER POWER GAIN
— FORWARD TRANSMISSION LOSS
OR INSERTION GAIN
21
POWER REFLECTED
FROM OUTPUT PORT
S
12
S
— OUTPUT RETURN LOSS
S
=
22
POWER AVAILABLE FROM
GENERATOR AT OUTPUT PORT
a. Two-Port Network Defined
b.
SR00233
Figure 19.
8
1997 Nov 07
Philips Semiconductors
Product specification
Wide-band high-frequency amplifier
SA5205A
50Ω System
75Ω System
25
20
25
v
= 8v
cc
= 7v
v
= 8v
v
cc
= 7v
cc
v
cc
20
15
v
= 6v
cc
v
v
2
= 6v
cc
= 5v
15
10
cc
v
= 5v
cc
Z
T
= 75Ω
= 25 C
O
A
Z
T
= 50Ω
= 25 C
O
A
o
o
10
1
2
4
6
8
2
2
4
6
8
3
10
10
10
1
2
4
6
8
2
4
6
8
3
10
10
10
FREQUENCY—MHz
FREQUENCY—MHz
a. Insertion Gain vs Frequency (S
)
b. Insertion Gain vs Frequency (S
)
21
21
10
10
–15
Z
T
= 75Ω
= 25 C
–15
O
A
o
V
= 6V
CC
V
= 6V
–20
–25
–30
CC
–20
–25
Z
T
= 50Ω
O
o
= 25 C
A
–30
1
2
4
6
8
2
2
4
6
8
3
10
1
2
4
6
8
2
2
4
6
8
3
10
10
10
FREQUENCY—MHz
10
10
FREQUENCY—MHz
c. Isolation vs Frequency (S
)
d. S Isolation vs Frequency
12
12
40
35
30
40
35
30
OUTPUT
OUTPUT
INPUT
25
20
25
20
V
= 6V
CC
Z
= 50Ω
O
INPUT
2
o
V
Z
= 6V
CC
T
= 25 C
A
15
10
= 75Ω
15
10
O
o
T
= 25 C
A
1
2
4
6
8
2
2
4
6
8
3
10
1
2
4
6
8
2
4
6
8
3
10
10
10
10
10
FREQUENCY—MHz
FREQUENCY—MHz
e. Input (S ) and Output (S ) Return Loss
f. Input (S ) and Output (S ) Return Loss
11 22
11
22
vs Frequency
vs Frequency
SR00234
Figure 20.
9
1997 Nov 07
Philips Semiconductors
Product specification
Wide-band high-frequency amplifier
SA5205A
The most important parameter is S . It is defined as the square root
of the power gain, and, in decibels, is equal to voltage gain as
shown below:
1dB from its low power value. The decrease is due to nonlinearities
in the amplifier, an indication of the point of transition between
small-signal operation and the large signal mode.
21
Z =Z =Z
for the SA5205A
The saturated output power is a measure of the amplifier’s ability to
deliver power into an external load. It is the value of the amplifier’s
output power when the input is heavily overdriven. This includes the
sum of the power in all harmonics.
D
IN OUT
SA5205
A
2
2
VOUT
ZD
VIN
POUT
)
PIN
)
ZD
Z
D
2
VOUT
ZD
2
INTERMODULATION INTERCEPT TESTS
POUT
PIN
VOUT
N
+
+
+ PI
The intermodulation intercept is an expression of the low level
linearity of the amplifier. The intermodulation ratio is the difference in
dB between the fundamental output signal level and the generated
distortion product level. The relationship between intercept and
intermodulation ratio is illustrated in Figure 22, which shows product
output levels plotted versus the level of the fundamental output for
two equal strength output signals at different frequencies. The upper
line shows the fundamental output plotted against itself with a 1dB to
1dB slope. The second and third order products lie below the
fundamentals and exhibit a 2:1 and 3:1 slope, respectively.
2
2
VIN
VIN
ZD
2
P =V
I
I
P =Insertion Power Gain
I
V =Insertion Voltage Gain
I
Measured value for the
SA5205A = |S
2
|
= 100
21
The intercept point for either product is the intersection of the
extensions of the product curve with the fundamental output.
POUT
2
NPI
+
+ | S21
|
+ 100
PIN
VOUT
The intercept point is determined by measuring the intermodulation
ratio at a single output level and projecting along the appropriate
product slope to the point of intersection with the fundamental.
When the intercept point is known, the intermodulation ratio can be
determined by the reverse process. The second order IMR is equal
to the difference between the second order intercept and the
fundamental output level. The third order IMR is equal to twice the
difference between the third order intercept and the fundamental
output level. These are expressed as:
Ǹ
and VI
+
+
PI + S21 + 10
VIN
In decibels:
2
P
=10 Log | S
|
= 20dB
I(dB)
I(dB)
21
V
= 20 Log S = 20dB
21
∴ P
= V
= S
= 20dB
I(dB)
I(dB)
21(dB)
IP =P
+IMR
2
2
OUT
OUT
OUT
Also measured on the same system are the respective voltage
standing wave ratios. These are shown in Figure 21. The VSWR
can be seen to be below 1.5 across the entire operational frequency
range.
IP =P
3
+IMR /2
3
where P
is the power level in dBm of each of a pair of equal
level fundamental output signals, IP and IP are the second and
2
3
Relationships exist between the input and output return losses and
the voltage standing wave ratios. These relationships are as follows:
third order output intercepts in dBm, and IMR and IMR are the
second and third order intermodulation ratios in dB. The
2
3
intermodulation intercept is an indicator of intermodulation
INPUT RETURN LOSS=S dB
11
performance only in the small signal operating range of the amplifier.
Above some output level which is below the 1dB compression point,
the active device moves into large-signal operation. At this point the
intermodulation products no longer follow the straight line output
slopes, and the intercept description is no longer valid. It is therefore
S
dB=20 Log | S
|
11
11
OUTPUT RETURN LOSS=S dB
22
S
22
dB=20 Log | S
|
22
INPUT VSWR=≤1.5
important to measure IP and IP at output levels well below 1dB
2
3
OUTPUT VSWR=≤1.5
compression. One must be careful, however, not to select too low
levels because the test equipment may not be able to recover the
signal from the noise. For the SA5205A we have chosen an output
level of -10.5dBm with fundamental frequencies of 100.000 and
100.01MHz, respectively.
1dB GAIN COMPRESSION AND SATURATED
OUTPUT POWER
The 1dB gain compression is a measurement of the output power
level where the small-signal insertion gain magnitude decreases
10
1997 Nov 07
Philips Semiconductors
Product specification
Wide-band high-frequency amplifier
SA5205A
2.0
2.0
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
1.1
1.0
1.9
o
T
= 25 C
= 6V
1.8
1.7
1.6
1.5
1.4
1.3
1.2
1.1
1.0
A
CC
o
T
= 25 C
amb
V
V
= 6V
CC
.
Z
Z
= 75Ω
O
O
Z
Z
= 75Ω
= 50Ω
2
O
O
= 50Ω
1
2
4
6
8
2
2
4
6
8
3
1
4
6
8
2
2
4
6
8
3
10
10
10
FREQUENCY—MHz
10
10
10
FREQUENCY—MHz
a. Input VSWR vs Frequency
b. Output VSWR vs Frequency
SR00235
Figure 21. Input/Output VSWR vs Frequency
“S-Parameter Techniques for Faster, More Accurate Network Design”,
HP App Note 95-1, Richard W. Anderson, 1967, HP Journal.
ADDITIONAL READING ON SCATTERING
PARAMETERS
For more information regarding S-parameters, please refer to
High-Frequency Amplifiers by Ralph S. Carson of the University of
Missouri, Rolla, Copyright 1985; published by John Wiley & Sons,
Inc.
“S-Parameter Design”, HP App Note 154, 1972.
+30
THIRD ORDER
INTERCEPT POINT
2ND ORDER
INTERCEPT
POINT
+20
1dB
COMPRESSION POINT
+10
FUNDAMENTAL
RESPONSE
0
-10
-20
-30
-40
2ND ORDER
RESPONSE
3RD ORDER
RESPONSE
-60
-50
-40
-30
-20
-10
0
+10
+20
+30
+40
INPUT LEVEL dBm
SR00236
Figure 22.
11
1997 Nov 07
Philips Semiconductors
Product specification
Wide-band high-frequency amplifier
SA5205A
SO8: plastic small outline package; 8 leads; body width 3.9mm
SOT96-1
12
1997 Nov 07
Philips Semiconductors
Product specification
Wide-band high-frequency amplifier
SA5205A
DEFINITIONS
Data Sheet Identification
Product Status
Definition
This data sheet contains the design target or goal specifications for product development. Specifications
may change in any manner without notice.
Objective Specification
Formative or in Design
This data sheet contains preliminary data, and supplementary data will be published at a later date. Philips
Semiconductors reserves the right to make changes at any time without notice in order to improve design
and supply the best possible product.
Preliminary Specification
Product Specification
Preproduction Product
Full Production
This data sheet contains Final Specifications. Philips Semiconductors reserves the right to make changes
at any time without notice, in order to improve design and supply the best possible product.
Philips Semiconductors and Philips Electronics North America Corporation reserve the right to make changes, without notice, in the products,
including circuits, standard cells, and/or software, described or contained herein in order to improve design and/or performance. Philips
Semiconductors assumes no responsibility or liability for the use of any of these products, conveys no license or title under any patent, copyright,
or mask work right to these products, and makes no representations or warranties that these products are free from patent, copyright, or mask
work right infringement, unless otherwise specified. Applications that are described herein for any of these products are for illustrative purposes
only. PhilipsSemiconductorsmakesnorepresentationorwarrantythatsuchapplicationswillbesuitableforthespecifiedusewithoutfurthertesting
or modification.
LIFE SUPPORT APPLICATIONS
Philips Semiconductors and Philips Electronics North America Corporation Products are not designed for use in life support appliances, devices,
orsystemswheremalfunctionofaPhilipsSemiconductorsandPhilipsElectronicsNorthAmericaCorporationProductcanreasonablybeexpected
to result in a personal injury. Philips Semiconductors and Philips Electronics North America Corporation customers using or selling Philips
Semiconductors and Philips Electronics North America Corporation Products for use in such applications do so at their own risk and agree to fully
indemnify Philips Semiconductors and Philips Electronics North America Corporation for any damages resulting from such improper use or sale.
Philips Semiconductors
811 East Arques Avenue
P.O. Box 3409
Copyright Philips Electronics North America Corporation 1997
All rights reserved. Printed in U.S.A.
Sunnyvale, California 94088–3409
Telephone 800-234-7381
Philips
Semiconductors
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