ANADIGICS ARA05050RS12P1

ARA05050
Reverse Amplifier with Step Attenuator
Data Sheet - Rev 2.7
features
• Low Cost Integrated Monolothic GaAs Amplifier
With Step Attenuator
• Attenuation Range: 0-30 dB, Adjustable In
2dB Increments Via a 4 Wire Parallel Control
• Meets DOCSIS Distortion Requirements at
+58dBmV Output Signal Level
• Low Distortion and Low Noise
• Low Signal toNoise Ratio at All Gain Levels
• Frequency Range: 5-100 MHz
• 5 Volt Operation
• RoHS-Compliant Package Option
Applications
S12 Package
28 Pin SSOP with Heat Slug
• MCNS/DOCSIS Compliant Cable Modems
• CATV Interactive Set-Top Box
• OpenCable Set-Top Box
• Fiber Nodes
• Cable Modem Termination Systems (CMTS)
product description
The ARA05050 is a GaAs IC designed to provide the
reverse path amplification and output level control
functions in a CATV Set-Top Box or Cable Modem.
It incorporates a digitally controlled precision step
attenuator that is preceded by an ultra low noise
amplifier stage, and followed by an ultra-linear output
driver amplifier. This device is capable of meeting
the MCNS/DOCSIS requirements for harmonic
4
Switch
performance at a +58dBmV output level while requiring
only a single polarity +5V supply. Both the input
and the output are single-ended and matched to 75
Ohms. The precision attenuator provides up to 30 dB
of attenuation in 2 dB increments. The ARA05050 is
offered in a 28-pin SSOP package that features a heat
slug on the bottom of the package, and is available in
a RoHS-compliant option.
Attenuation Control
LPF
ARA05050
Balun
Upstream
QPSK/16QAM
Modulator
RAM
Clock
Microcontroller
with Ethernet
MAC
MAC
Clock
Diplexer
Data
Transmit Enable/Disable
5-42 MHz
54-860 MHz
DoubleConversion
Tuner
44 MHz
SAW
Filter
QAM Receiver
with FEC
Data
10Base-T
Transceiver
Figure 1. Cable Modem or Set Top Box Application Diagram
04/2012
ROM
RJ45
Connector
ARA05050
RF OUT1
ATT IN
ATT OUT
RF IN2
30 dB, 2dBstep digital attenuator section
RF IN
A1
A2
ISET1
16 dB
8 dB
4 dB
2 dB
ISET2
Figure 2: Functional Block Diagram
1
N/C
N/C
28
2
Bypass
N/C
27
3
ATTIN
ATTOUT
26
4
RF OUT1
ISET2
25
5
VREF1
RFIN2
24
6
ATTACG1
ATTACG2
23
7
ATTACG1
ATTACG2
22
8
ATTACG1
ATTACG2
21
9
ATTACG1
ATTACG2
20
10
RF IN
VREF2
19
11
ISET1
RF OUT2
18
12
VATT
GND
17
13
16 dB
2 dB
16
14
8 dB
4 dB
15
Figure 3: Pinout
2
Data Sheet - Rev 2.7
04/2012
RF OUT2
ARA05050
Table 1: Pin Description
PIN
NAME
1
N/C
2
Bypass
3
ATTIN
4
PIN
NAME
No Connection(1)
28
N/C
No Connection (1)
Internal Bypass
27
N/C
No Connection (1)
Attenuator Input(2)
26
ATTOUT
RFOUT1
Amplifier A1 Output and Supply
25
ISET2
Amplifier A2 Current Adjust (4)
5
VREF1
Reference Voltage for Amplifier
A1
24
RFIN2
Amplifier A2 Input (4)
6
ATTACG1
Attenuator AC Ground 1(3)
23
ATTACG2 Attenuator AC Ground 2
(3)
ATTACG1
Attenuator AC Ground 1(3)
22
ATTACG2 Attenuator AC Ground 2
(3)
8
ATTACG1
Attenuator AC Ground 1(3)
21
ATTACG2 Attenuator AC Ground 2
(3)
9
ATTACG1
Attenuator AC Ground 1(3)
20
ATTACG2 Attenuator AC Ground 2
(3)
10
RFIN
Amplifier A1 Input(4)
19
VREF2
11
ISET1
Amplifier A1 Current Adjust(4)
18
RFOUT2
12
VATT
Attenuator Supply
17
GND
Ground
13
16 dB
16 dB Attenution Control Bit
16
2 dB
2 dB Attenuition Control Bit
14
8 dB
8 dB Attenution Control Bit
15
4 dB
4 dB Attenuition Control Bit
7
DESCRIPTION
DESCRIPTION
Attenuator Output (2)
Reference Voltage for Amplifier A2
Amplifier A2 Output and Supply
Notes:
(1) All N/C pins should be grounded.
(2) Pins should be AC-coupled. No external DC bias should be applied.
(3) Pins should be AC-grounded. No external DC bias should be applied.
(4) Pins should be grounded or pulled to ground through a resistor. No external DC bias should be applied.
3
Data Sheet - Rev 2.7
04/2012
ARA05050
electrical characteristics
Table 2: Absolute Minimum and Maximum Ratings
PARAMETER
MIN
MAX
UNIT
0
9
VDC
Amplifier Reference Voltages (pins 5, 19)
-2.5
VSUP
2
VDC
RF Power at Amplifier Inputs (pins 10, 24)
-
+60
dBmV
Attenuator Controls (pins 13, 14, 15, 16)
0
6
V
-55
+200
°C
Soldering Temperature
-
260
°C
Soldering Time
-
5
Sec
Analog Supply: VSUP (pins 4, 12, 18)
Storage Temperature
Stresses in excess of the absolute ratings may cause permanent damage. Functional
operation is not implied under these conditions. Exposure to absolute ratings for
extended periods of time may adversely affect reliability.
Notes:
1. Pins 3 and 26 should be AC-coupled. No external DC bias should be applied.
2. Pins 10, 11, 24 and 25 should be grounded or pulled to ground through a resistor. No
external DC bias should be applied.
3. Pins 6, 7, 8, 9, 20, 21, 22 and 23 should be AC-grounded. No external DC bias should
be applied.
Table 3: Operating Ranges
PARAMETER
MIN
TYP
MAX
UNIT
Amplifier Supply: VDD (pins 4, 18)
4.5
5
7
VDC
Attenuator Supply: VATTN (pin 12)
-
5
7
VDC
Attenuator Controls (pins 13, 14, 15, 16)
0
-
5.5
V
Amplifier Reference Voltages (pins 5, 19)
-
1.75
-
VDC
Output Switch Control (pin 25)
0
-
5.5
V
-40
25
85
°C
Case Temperature
The device may be operated safely over these conditions; however, parametric performance is
guaranteed only over the conditions defined in the electrical specifications.
4
Data Sheet - Rev 2.7
04/2012
ARA05050
Table 4: DC Electrical Specifications
TA=25°C; VDD, Vattn = +5.0 VDC
PARAMETER
MIN
TYP
MAX
UNIT
Amplifier A1 Current (pin 4)
-
75
95
mA
Amplifier A2 Current (pin 18)
-
100
130
mA
Attenuator Current (pin 12)
-
8
-
mA
Total Power Consumption
-
0.92
1.2
W
Thermal Resistance (JC)
-
36
-
C/W
COMMENTS
Table 5: AC Electrical Specifications
TA=25°C; VDD, Vattn = +5.0 VDC
PARAMETER
MIN
TYP
MAX
UNIT
Gain (10 MHz)
31
32
33
dB
0 dB attenuation setting
Gain Flatness
-
0.75
1.5
dB
5 to 100 MHz
Gain Variation over Temperature
-
-0.006
-
dB/°C
1.6
3.8
8.0
16.0
1.85
4.0
8.3
16.6
2.2
4.2
8.5
17.0
2nd Harmonic Distortion Level
5 MHz
25 MHz
-
-60
-63
3rd Harmonic Distortion Level
5 MHz
25 MHz
-
Attenuation Steps
2 dB
4 dB
8 dB
16 dB
dB
5 to 42 MHz (1),
Monotonic
-55
-55
dBc
+58 dBmV into 75 Ohms
-63
-63
-60
-60
dBc
+58 dBmV into 75 Ohms
78
-
-
dBmV
1 dB Gain Compression Point
-
70
-
dBmV
Noise Figure
-
1.7
2.5
dB
3rd Order Output Intercept
Notes:
(1) See Figures 5 and 6 for performance at higher frequencies.
All specifications as measured in ANADIGICS test fixture.
5
COMMENTS
Data Sheet - Rev 2.7
04/2012
ARA05050
continued: AC Electrical Specifications
TA=25°C; VDD, Vattn = +5.0 VDC
MIN
TYP
MAX
UNIT
COMMENTS
Output Noise Power
Active/No Signal/Min. Atten. Set.
Active/No Signal/Max. Atten. Set.
-
-
-
dBmV
Any 160 kHz bandwidth
from 5 to 42 MHz
Input Impedance
-
-75
-
Ohms
Input Return Loss
-
-20
-15
dB
Output Impedance
-
75
-
Ohms
Output Return Loss
-
-20
-15
dB
PARAMETER
75  system
75  system
Note: As measured in ANADIGICS test fixture
Table 6: Logic Interface Specifications
TA=25°C; VDD, Vattn = +5.0 VDC
PARAMETER
MIN
TYP
MAX
UNIT
Attenuator Control Logic
VIN,LOW
VIN,HIGH
0
2.8
-
0.5
5.5
V
-
5K
-
Ohms
Attenuator Control Impedance
COMMENTS
Bypasses atten. stage
Enables atten. stage
Note:
(1) Specification applies when 470 Ohm resistor is connected from pin 2 to ground (see test circuit in Figure 4).
Table 7: Attenuator Logic
ATTENUATION (dB)
0
2
4
6
8
10
12
14
16
18 20
22
24
26
28
30
2 dB Logic Input (pin 16)
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
4 dB Logic Input (pin 15)
L
L
H
H
L
L
H
H
L
L
H
H
L
L
H
H
8 dB Logic Input (pin 14)
L
L
L
L
H
H
H
H
L
L
L
L
H
H
H
H
16 dB Logic Input (pin 13)
L
L
L
L
L
L
L
L
H
H
H
H
H
H
H
H
Note: “L” = logic low, “H” = logic high
6
Data Sheet - Rev 2.7
04/2012
Figure 4: Test Circuit
Data Sheet - Rev 2.7
04/2012
3.9 Ohms
RF Input
(75 Ohms)
Ohms
+5 V
0.01uF
N t
Th 470 Ohm
nt
1uF
0.1uF
0.8pF + 0.1pF
620 Ohms
0.1uF
20 Ohms
10uH
16 dB
Ohms
1.8
1000pF
3.3
0.01uF
1uF
Ohms
s ts
.s F
5
14
13
12
11
10
9
8
7
6
5
4
3
2
1
Ohms
8 dB
ARA05050
4 dB
2 dB
GND
V ATTN
16 dB
RF OUT
ATT ACG2
ATTACG1
ISET1
ATT ACG2
ATTACG1
V REF2
ATT ACG2
ATTACG1
RFIN
ATT ACG2
RFIN2
V REF1
ATTACG1
ISET2
ATTOUT
N/C
N/C
RFOUT1
ATTIN
Bypass
N/C
15
16
17
18
19
20
21
22
23
24
25
26
27
28
4 dB
m p n2 t
und snsta
d 3V att nuat
5V
th 470 Ohm s ts
s m
d.
0.01uF
5
0.1uF
1uF
0.01uF
0.1uF
470 Ohms
(s
n t )
8 dB
7
20 Ohms
1uF
1uF
0.01uF
0.1uF
2 dB
+5 V
0.01uF
Ohms
Ohms
0.1uF
0.01uF
5
Ohms
3.3
1.8
+5 V 1uF
10uH
Ohms
0.1uF
620 Ohms
1uF
5
RF
Output
(75 Ohms)
ARA05050
ARA05050
performance data
8
Figure 5: S21 (0 - 16 dB Attenuation)
Figure 6: S21 (16 - 30 dB Attenuation)
Figure 7: S11 - Log Scale
Figure 8: S22 - Log Scale
Figure 9: S11 - Smith Chart
Figure 10: S22 - Smith Chart
Data Sheet - Rev 2.7
04/2012
ARA05050
Figure 11: Attenuator Switching Speed - 16 dB Step
Figure 12: Harmonic Performance
9
Data Sheet - Rev 2.7
04/2012
ARA05050
application information
Printed Circuit Board Layout Considerations
The ARA05050 is a high-performance RF device.
Special consideration must be given to certain features
of the the printed circuit board layout, as they can
affect the RF performance of the IC. Refer to the
ANADIGICS application note “CATV Reverse Amp w/
Step Attenuator” for more details.
Thermal Layout Considerations
The device package for the ARA05050 features a
heat slug on the bottom of the package body. Use of
the heat slug is an integral part of the device design.
Soldering it to the ground plane of the PC board will
ensure the lowest possible thermal resistance for the
device, and will result in the longest MTF (mean time
to failure.)
Amplifier Enable / Disable
The ARA05050 includes two amplification stages
that each can be shut down through external control
pins Vref1 and Vref2 (pins 5 and 19, respectively.)
By applying a typical bias of 1.75 Volts to these pins,
the amplifiers are enabled. In order to fully disable
an amplifier, its control pin requires a negative bias
of -1.5 to -2.0 Volts.
A PC board layout that optimizes the benefits of the
heat slug is shown in Figure 13. The via holes located
under the body of the device must be plated through
to a ground plane layer of metal, in order to provide
sufficient thermal conductivity. The recommended
solder mask outline is shown in Figure 14.
Amplifier Bias Current
The Iset pins (11 and 25) set the bias current for the
amplification stages. Grounding these pins results
in the maximum possible current. By placing a
resistor from the pin to ground, the current can be
reduced. The recommended bias conditions use the
configuration shown in the test circuit schematic in
Figure 4.
0.025BSC
ESD Sensitivity
Electrostatic discharges can cause permanent damage
to this device. Electrostatic charges accumulate on test
equipment and the human body, and can discharge
without detection. Proper precautions and handling
are strongly recommended. Refer to the ANADIGICS
application note on ESD precautions.
0.089
0.014TYP
BODY OUTLINE
(NOMINAL
)
0.025MIN.
0.163
0.099
0.070 0.1520.150
REF.
0.197
0.060TYP.
0.386REF.
0.400
Figure 13: PC Board Layout
10
Data Sheet - Rev 2.7
04/2012
(12X)0.020
TO 0.060DIA.P
PLATED THRU HOLES.
ARA05050
0.016TYP.
0.091
0.053
0.025TYP.
0.163
0.242
0.085
0.098
0.025BSC
0.145
DIMENSIONSARE IN INCHES
Figure 14: Solder Mask Outline
11
Data Sheet - Rev 2.7
04/2012
ARA05050
PACKAGE OUTLINE
Figure 15: S12 Package Outline - 28 Pin SSOP with Heat Slug
12
Data Sheet - Rev 2.7
04/2012
ARA05050
COMPONENT PACKAGING
Volume quantities of the ARA05050 are supplied on
tape and reel. Each reel holds 3,500 pieces. Smaller
quantities are available in plastic tubes of 50 pieces.
Figure 16: Reel Dimensions
Figure 17: Tape Dimensions
13
Data Sheet - Rev 2.7
04/2012
ARA05050
Ordering Information
ORDER NUMBER
TEMPERATURE
RANGE
PACKAGE
DESCRIPTION
ARA05050S12CTR
-40 to 85 0C
28 Pin SSOP
with Heat Slug
3,500 piece tape and reel
ARA05050S12C
-40 to 85 0C
28 Pin SSOP
with Heat Slug
Plastic tubes (50 pieces per tube)
ARA05050RS12P1
-40 to 85 0C
RoHS-compliant
28 Pin SSOP
with Heat Slug
COMPONENT PACKAGING
3,500 piece tape and reel
ANADIGICS, Inc.
141 Mount Bethel Road
Warren, New Jersey 07059, U.S.A.
Tel: +1 (908) 668-5000
Fax: +1 (908) 668-5132
URL: http://www.anadigics.com
E-mail: Mktg@anadigics.com
IMPORTANT NOTICE
ANADIGICS, Inc. reserves the right to make changes to its products or to discontinue any product at any time without notice.
The product specifications contained in Advanced Product Information sheets and Preliminary Data Sheets are subject to
change prior to a product’s formal introduction. Information in Data Sheets have been carefully checked and are assumed
to be reliable; however, ANADIGICS assumes no responsibilities for inaccuracies. ANADIGICS strongly urges customers
to verify that the information they are using is current before placing orders.
warning
ANADIGICS products are not intended for use in life support appliances, devices or systems. Use of an ANADIGICS product
in any such application without written consent is prohibited.
14
Data Sheet - Rev 2.7
04/2012