TAT8857
Applications
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•
•
•
CATV Doubler – Hybrid RFIC
CATV Line Amplifiers
CATV System Amplifiers
Distribution Nodes
Green Applications
SOIC-16 Wide Package
Product Features
•
•
•
•
•
•
75 Ω, 40
–
1000
MHz Bandwidth
GaAs pHEMT & MESFET Technology
21 – 27 dB configurable gain
Integrated linearization
Flexible bias voltage and current for optimum
efficiency
SOIC-16 Wide Package
Functional Block Diagram
General Description
The TAT8857 is a cost effective 75
Ω
RFIC Amplifier
designed for use in Doubler CATV applications up to 1000
MHz. It works with readily available SMT baluns and
transformers to provide a highly flexible low cost
replacement for traditional hybrids.
Gain of the TAT8857 may be easily adjusted by varying
external components, allowing for a family of Doubler
solutions to be developed from a single RFIC.
The TAT8857 provides integrated linearization to improve
the 3
rd
order distortion performance.
The TAT8857 may be protected against transient surges
with the
TQP200002 and an output high pass filter
network. Consult TriQuint for discussion.
The TAT8857 supports traditional 24
V and 12 V supply
voltages. Bias current may be adjusted to suit particular
requirements with standard or active biasing approaches.
Consult TriQuint for further discussion.
Pin Configuration
Pin #
1
2
3
4
5
6
7
8
9
Symbol
OUT 1A
LIN ADJ A
IN 1A
BIAS 1
BIAS 1
IN 1B
LIN ADJ B
OUT 1B
BIAS 2
Pin # Symbol
10
11
12
13
14
15
16
17
IN 2A
OUT 2A
GATE A
GATE B
OUT 2B
IN 2B
BIAS 2
GND
Ordering Information
Part No.
TAT8857
TAT8857-EB
RFIC
evaluation board
Description
Standard T/R size =
1000
pieces on a 7” reel.
Data Sheet: Rev B 03-08-12
© 2012 TriQuint Semiconductor, Inc.
-
1 of 8
-
Disclaimer: Subject to change without notice
Connecting the Digital World to the Global Network
®
TAT8857
CATV Doubler – Hybrid RFIC
Specifications
Absolute Maximum Ratings
Parameter
Storage Temperature
Recommended Operating Conditions
o
Rating
-65
to 150
C
Parameter
V
cc
I
cc
Min
Typ
24
350
Max Units
V
mA
Operation of this device outside the parameter ranges given
above may cause permanent damage.
Electrical specifications are measured at specified test conditions.
Specifications are not guaranteed over all recommended operating
conditions.
Electrical Specifications
Test conditions unless otherwise noted: 25ºC case temp,
+24V
Vsupply
Parameter
Operational Frequency Range
Test Frequency
Gain
Input Return Loss
Output Return Loss
Output P1dB
at 500 MHz
Output IP3
CTB
CSO
CIN
XMOD
Noise Figure
Vbias
Idd
Thermal Resistance (jnc. to case)
θ
jc
Conditions
Min
40
Typical
25
18
17
31
52
-73
-74
60
-68
4.0
24
350
3.4
Max
1000
Units
MHz
MHz
dB
dB
dB
dBm
dBm
dBc
dBc
dB
dBc
dB
V
mA
o
C/W
See Note 1
See Note 2
See Note 2
See Note 2
See Note 2
See Note 3
Notes:
1.
100 MHz tone spacing, tone 1 at 225 MHz, tone 2 at 325 MHz, low
and high side intermod products.
2.
79ch. NTSC + QAM (6dB offset) to 1003.25MHz, 13dB uptilt from 55.25MHz to 1003.25MHz, 40dBmV/ch at 55.25 MHz
and the
equivalent of 53
dBmV/ch at 1003.25 MHz.
3. Active biasing in easily implemented with traditional dual-pnp approaches. Biasing at 12 V is also possible.
Data Sheet: Rev B 03-08-12
© 2012 TriQuint Semiconductor, Inc.
-
2 of 8
-
Disclaimer: Subject to change without notice
Connecting the Digital World to the Global Network
®
TAT8857
CATV Doubler – Hybrid RFIC
Application Circuit 40-1000 MHz
+24v
GND
R7 180 L9 82nH
C7 .01uF
R1 27k
L5
15nH
C27 0.7pF
R9 100
C11 0.01u
L11
470nH
1
BIAS 2A
16
J1
L20 910nH
Vbias
C24
.033uF
C25
.033uF
R18
2.7K
Vgate
C9 82pF
C13 0.01uF
C15 2.2pF
L15
9nH
R3
390
R19
2K
R20
33
R5 8.09k
2
MABACT0051
3
4
1
LIN ADJ A
UPPER A
15
L13
27nH
R11 18
R13
1.3k
L19 600
1
2
R15
43
L17
8.2nH
C17
0.5pF
C3
.01uF
2
3
3
14
LOWER A
BIAS 1A
C5
1.8pF
R21 5.1
L7 600
1
T2
2 to 1
BALUN
2
OUT1
IN
3
SEC
OUT2
PRI
GND
4
1
2
1
4
2
5
2
6
U1
8857D
13
GATE A
12
L30
3.9nH
Vbias
C22
.01uF
C2
.01uF
1
RF
IN
T1
C4
.01uF
C6
1.8pF
5.1
BIAS 1B
TAT8857F3
LOWER B
GATE B
11
Vgate
R12 18
L14
27nH
R14
1.3k
43
R16
L8 600
R6 8.09k
L18
8.2nH
0.5pF
C18
MABA-007681
-CT2010
RF
OUT
7
LIN ADJ B
8
UPPER B
BIAS 2B
10
9
L6
15nH
C28 0.7pF
R2
27k
R10 100
C12 0.01u
L12
470nH
R21
33
L16
9nH
R4
390
C8 .01uF
R8 180 L10 82nH
C10 82pF
C14 0.01uF
2.2pF
C16
Data Sheet: Rev B 03-08-12
© 2012 TriQuint Semiconductor, Inc.
-
3 of 8
-
Disclaimer: Subject to change without notice
Connecting the Digital World to the Global Network
®
TAT8857
CATV Doubler – Hybrid RFIC
Typical Performance 40-1000 MHz
Notes:
1.
25ºC case
temp, 24V supply,.
2.
79ch. NTSC + QAM (6dB offset) to 1003.25MHz, 13dB uptilt from 55.25MHz to 1003.25MHz, 40dBmV/ch
at 55.25 MHz and the
equivalent of 53 dBmV/ch at 1003.25 MHz
30
29
Input Return Loss (dB)
Gain vs. Frequency
0
-5
-10
-15
-20
-25
-30
-35
0.00
Input Return Loss vs. Frequency
Output Return Loss (dB)
0
-5
-10
-15
-20
-25
-30
-35
0.00
Output Return Loss vs. Frequency
28
27
Gain (dB)
26
25
24
23
22
21
20
0.00
200.00
400.00
600.00
+85
°
C
+25
°
C
−40
°
C
+85
°
C
+25
°
C
−40
°
C
+85
°
C
+25
°
C
−40
°
C
800.00 1000.00 1200.00
200.00
400.00
600.00
800.00 1000.00 1200.00
200.00
400.00
600.00
800.00 1000.00 1200.00
Frequency (MHz)
Frequency (MHz)
Frequency (MHz)
35
34
33
32
P1dB (dBm)
P1dB vs. Frequency
7
6
5
NF (dB)
Noise Figure vs. Frequency
70
65
60
CIN (dB)
CIN vs. Frequency
31
30
29
28
27
26
25
0.00
200.00
400.00
600.00
800.00 1000.00 1200.00
+85
°
C
+25
°
C
−40
°
C
4
3
2
1
0
0.00
+85
°
C
+25
°
C
−40
°
C
55
50
45
40
0.00
+85
°
C
+25
°
C
−40
°
C
200.00
400.00
600.00
800.00 1000.00 1200.00
100.00
200.00
300.00
400.00
500.00
600.00
Frequency (MHz)
Frequency (MHz)
Frequency (MHz)
-60
-65
-70
-75
-80
-85
-90
0.00
CTB vs. Frequency
-60
-65
-70
-75
-80
-85
-90
0.00
CSO vs. Frequency
-50
-55
-60
-65
-70
-75
-80
0.00
XMOD vs. Frequency
XMOD (dBc)
CSO (dBc)
CTB (dBc)
+85
°
C
+25
°
C
−40
°
C
+85
°
C
+25
°
C
−40
°
C
+85
°
C
+25
°
C
−40
°
C
100.00
200.00
300.00
400.00
500.00
600.00
100.00
200.00
300.00
400.00
500.00
600.00
100.00
200.00
300.00
400.00
500.00
600.00
Frequency (MHz)
Frequency (MHz)
Frequency (MHz)
Data Sheet: Rev B 03-08-12
© 2012 TriQuint Semiconductor, Inc.
-
4 of 8
-
Disclaimer: Subject to change without notice
Connecting the Digital World to the Global Network
®
TAT8857
CATV Doubler – Hybrid RFIC
Detailed Device Description
The TAT8857 is similar to other parts offered on the market; it contains two separate amplifiers. A major difference is the
TAT8857 allows much flexibility to set gain and bias to cover multiple applications without an additional stage. This makes it
ideal for green designs. It uses a cost effective high voltage MESFET technology (designed for CATV) and a pHEMT process
(developed for high-volume applications). On-chip linearization is also utilized.
Bias Current Adjustment
R7 180 L9 82nH
C7 .01uF
R1 27k
L5
15nH
C27 0.7pF
R9 100
C11 0.01u
L1
47
1
BIAS 2A
16
C9 82pF
C13
R3
390
R5 8.09k
2
LIN ADJ A
UPPER A
15
Bias current is determined by 2 settings:
1. Size of DC feedback resistors - decreasing
R1 & R2 will increase IDD
2. Tail resistors - decreasing R21 will
increase IDD, but lead to wider variations
Active biasing schemes are possible but not
necessary for most applications.
Best performance is with IDD = 350mA
L6
15nH
3
14
LOWER A
BIAS 1A
R21 5.1
L7 600
1
4
2
5
2
6
U1
8857D
13
GATE A
12
R11
1
5.1
BIAS 1B
TAT8857F3
LOWER B
GATE B
11
L8 600
R6 8.09k
R12
7
LIN ADJ B
8
UPPER B
BIAS 2B
10
9
C28 0.7pF
R2
27k
R10 100
C12 0.01u
L1
47
R4
390
C8 .01uF
R8 180 L10 82nH
C10 82pF
C14
Voltage Biasing: 24V and 12V
The TAT8857 has two amplifiers which can be configured to split a 24 V supply (and share the same current) or both
amplifiers can be biased from a 12V supply and draw current independently.
Data Sheet: Rev B 03-08-12
© 2012 TriQuint Semiconductor, Inc.
-
5 of 8
-
Disclaimer: Subject to change without notice
Connecting the Digital World to the Global Network
®