ANADIGICS ARA2000

ARA2000
Address-Programmable Reverse
Amplifier with Step Attenuator
Data Sheet - Rev 2.3
features
• Low cost integrated amplifier with step attenuator
• Attenuation Range: 0-58 dB, adjustable in 1dB
increments via a 3 wire serial control
• Meets DOCSIS distortion requirements at a
+60dBmV output signal level
• Programmable address allows multiple parts to
share control bus
• Low distortion and low noise
• Frequency range: 5-100MHz
• 5 Volt operation
• -40 to +85 oC temperature range
Applications
• MCNS/DOCSIS Compliant Cable Modems
S12 Package
28 Pin SSOP
with Heat Slug
• CATV Interactive Set-Top Box
• Telephony over Cable Systems
• OpenCable Set-Top Box
• Residential Gateway
product description
The ARA2000 is 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 uses a balanced circuit design that exceeds the
MCNS/DOCSIS requirement for harmonic performance
at a +60dBmV output level while only requiring a single
polarity +5V supply. Both the input and output are
matched to 75 ohms with an appropriate transformer.
The precision attenuator provides up to 58 dB of
attenuation in 1 dB increments. The ARA2000 has a
programmable address that allows multiple devices to
share a common control bus. The ARA2000 is offered
in a 28-pin SSOP package featuring a heat slug on
the bottom of the package.
Figure 1: Cable Modem or Set Top Box Application Diagram
04/2011
ARA2000
Figure 2: Functional Block Diagram
Figure 3: Pin Out
2
Data Sheet - Rev 2.3
04/2011
ARA2000
Table 1: Pin Description
pin
nAMe
1
GND
2
descRiption
pin
nAMe
descRiption
Ground
15
C0
Device Address 0
VATTN
Supply for Attenuator
16
C1
Device Address 1
3
ATTIN (+)
Attenuator (+) Input (2)
17
N/C
No Connection (1)
4
A1OUT (+)
Amplifier A1 (+) Output
18
GND CMOS
Ground for Digital CMOS
Circuit
5
A1IN (+)
Amplifier A1 (+) Input (2)
19
ATTOUT (-)
Attenuator (-) Output (2)
6
Vg1
Amplifier A1 (+/-) Control
20
A2IN (-)
Amplifier A2 (-) Input (2)
7
ISET1
Amplifier A1 (+/-) Current
Adjust
21
A2OUT (-)
Amplifier A2 (-) Output
8
A1IN (-)
Amplifier A1 (-) Input (2)
22
ISET2
Amplifier A2 (+/-) Current
Adjust
9
A1OUT (-)
Amplifier A1 (-) Output
23
Vg2
Amplifier A2 (+/-) Control
10
ATTIN (-)
Attenuator (-) Input (2)
24
A2OUT (+)
Amplifier A2 (+) Output
11
VCMOS
Supply For Digital CMOS
Circuit
25
A2IN (+)
Amplifier A2 (+) Input (2)
12
CLK
Clock
26
ATTOUT (+)
Attenuator (+) Output (2)
13
DAT
Data
27
N/C
No Connection (1)
14
EN
Enable
28
GND
Ground
Notes:
(1) All N/C pins should be grounded.
(2) Pins should be AC-coupled. No external DC bias should be applied.
Data Sheet - Rev 2.3
04/2011
3
ARA2000
electrical characteristics
Table 2: Absolute Minimum and Maximum Ratings
pARAMeteR
Min
MAX
unit
Analog Supply (pins 2, 4, 9, 21, 24)
0
9
VDC
Digital Supply: VCMOS (pin 11)
0
6
VDC
Amplifier Controls Vg1, Vg2 (pins 6, 23)
-5
2
V
RF Power at Inputs (pins 5, 8)
-
+60
dBmV
Digital Interface (pins 12, 13, 14, 15, 16)
-0.5
VCMOS+0.5
V
Storage Temperature
-55
+200
C
Soldering Temperature
-
260
C
Soldering Time
-
5
Sec
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, 5, 8, 10, 19, 20, 25 and 26 should be AC-coupled. No external DC bias should be
applied.
2. Pins 7 and 22 should be grounded or pulled to ground through a resistor. No external DC
bias should be applied.
Table 3: Operating Ranges
pARAMeteR
Min
tYp
MAX
unit
Amplifier Supply: VDD (pins 4, 9,21,24)
4.5
5.0
7.0
VDC
VDD -0.5
5.0
7.0
VDC
3.0
-
5.5
VDC
Digital Interface (pins 12, 13, 14, 15,16)
0
-
VCMOS
V
Amplifier Controls Vg1, Vg2 (pins 6, 23)
-5
1
2
V
Case Temperature
-40
25
85
C
Attenuator Supply: VATTN (pin 2)
Digital Supply: VCMOS (pin 11)
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 2.3
04/2011
ARA2000
Table 4: DC Electrical Specifications
TA=25°C; VDD, VATTN, VCMOS = +5.0 VDC; Vg1, Vg2 = +1.0 V (TX enabled); Vg1, Vg2 = 0 V (TX disabled)
pARAMeteR
Min
tYp
MAX
unit
coMMents
Amplifier A1 Current (pins 4, 9)
-
48
2.4
80
6
mA
Tx enabled
Tx disabled
Amplifier A2 Current (pins 21, 24)
-
77
3.7
120
9
mA
Tx enabled
Tx disabled
Attenuator Current (pin 2)
-
9
15
mA
Total Power Consumption
-
0.67
75
1.08
150
W
mW
Thermal Resistance (JC)
-
38
-
C/W
Tx enabled
Tx disabled
Table 5: AC Electrical Specifications
TA=25°C; VDD, VATTN, VCMOS = +5.0 VDC; Vg1, Vg2 = +1.0 V (TX enabled); Vg1, Vg2 = 0 V (TX disabled)
Min
tYp
MAX
unit
Gain (10 MHz)
27.5
29.3
30.5
dB
0 dB attenuation setting
Gain Flatness
-
0.75
1.5
-
dB
5 to 42 MHz
5 to 65 MHz
Gain Variation over Temperature
-
-0.006
-
dB/8C
0.65
1.6
3.6
7.5
15.0
30.2
0.83
1.70
3.75
7.75
15.40
30.75
1.00
2.05
4.0
8.0
15.8
31.3
58.6
60.3
-
dB
2nd Harmonic Distortion Level
(10 MHz)
-
-75
-53
dBc
+60 dBmV into 75 Ohms
3rd Harmonic Distortion Level
(10 MHz)
-
-60
-53
dBc
+60 dBmV into 75 Ohms
78
-
-
dBmV
1 dB Gain Compression Point
-
68.5
-
dBmV
Noise Figure
-
3.0
4.0
dB
pARAMeteR
Attenuation Steps
1 dB
2 dB
4 dB
8 dB
16 dB
32 dB
Maximum Attenuation
3rd Order Output Intercept
dB
coMMents
Monotonic
Includes input balun loss
Note: As measured in ANADIGICS test fixture
Data Sheet - Rev 2.3
04/2011
5
ARA2000
continued: AC Electrical Specifications
TA=25°C; VDD, VATTN, VCMOS = +5.0 VDC; Vg1, Vg2 = +1.0 V (TX enabled); Vg1, Vg2 = 0 V (TX disabled)
pARAMeteR
Min
tYp
MAX
unit
coMMents
Output Noise Power
Active/ No Signal/ Min. Atten. Set
Active/ No Signal/ Max. Atten. Set.
-
-
-38.5
-53.8
dBmV
Any 160 kHz bandwidth from
5 to 42 MHz
Isolation (45 MHz) in Tx disable mode
-
65
-
dB
Difference in output signal
between Tx enable and Tx
disable
Differential Input Impedance
-
300
-
Ohms
between pins 5 and 8 (Tx
enabled)
Input Impedance
-
75
-
Ohms
with transformer (Tx enabled)
Input Return Loss
(75 Ohm characteristic impedance)
-
-20
-5
-12
-
dB
Differentail Output Impedance
-
300
-
Ohms
between pins 21 and 24
Output Impedance
-
75
-
Ohms
with transformer
Output Return Loss
(75 Ohm characteristic impedance)
-
-17
-15
-12
-10
dB
Output Voltage Transient
Tx enable/ Tx disable
-
4
100
7
mVp-p
Note: As measured in ANADIGICS test fixture
6
Data Sheet - Rev 2.3
04/2011
Tx enabled
Tx disabled
Tx enabled
Tx disabled
0 dB attenuator setting
24 dB attenuator setting
ARA2000
Figure 4: Test Circuit
Data Sheet - Rev 2.3
04/2011
7
ARA2000
PERFORMANCE DATA
Figure 5: Attenuation Level vs Control Word
Figure 6: Gain & Noise Figure vs Frequency
Figure 7: Gain & Noise Figure vs VDD
8
Data Sheet - Rev 2.3
04/2011
ARA2000
Figure 8: Gain & Noise Figure vs Temperature
Figure 9: Harmonic Distortion vs VDD
POUT = 58dBmV
Figure 10: Harmonic Distortion vs VDD
POUT = 58dBmV
Data Sheet - Rev 2.3
04/2011
9
ARA2000
Figure 11: Harmonic Distortion vs Temperature
POUT = 58dBmV
Figure 12: Harmonic Distortion vs Power Out
Figure 13: Transients vs Attenuation
POUT = 55dBmV at 0dB attenuation
10
Data Sheet - Rev 2.3
04/2011
ARA2000
Figure 14: Harmonic Performance over
Frequency POUT = +62dBmV
Figure 15: IIP2 & IIP3 vs Frequency
Figure 16: IIP2 & IIP3 vs VDD
Data Sheet - Rev 2.3
04/2011
11
ARA2000
LOGIC PROGRAMMING
Programming Instructions
The programming word is set through a 16 bit shift
register via the data, clock and enable lines. The
data is entered in order with the most significant bit
(MSB) first and the least significant bit (LSB) last. The
enable line must be low for the duration of the data
entry, then set high to latch the shift register. The
rising edge of the clock pulse shifts each data value
into the register.
Table 6: Programming Word
dAtA Bit
d15
d14
d13
d 12
d 11
d10
d9
d8
d7
d6
d5
d4
d3
d2
d1
d0
Value
P7
P6
P5
P4
P3
P2
P1
P0
0
0
0
1
C1
C0
1
1
Table 7: Data Description
12
Table 8: Device Address
VAlue
function
( 1 = on, 0 = bypass)
P7
N/A
P6
N/A
P5
loGic leVel input to
AddRess deVice
c1
c0
pin 16 (c1)
pin 15 (c0)
0
0
0
0
1
0
1
0
32 dB Attenuator Bit
0
1
0
1
P4
16 dB Attenuator Bit
1
1
1
1
P3
8 dB Attenuator Bit
P2
4 dB Attenuator Bit
P1
2 dB Attenuator Bit
P0
1 dB Attenuator Bit
The device is selected when the logic inputs at pins
16 and 15 match the values of data bits C1 and C0,
respectively.
Data Sheet - Rev 2.3
04/2011
ARA2000
Table 9: Digital Interface Specification
DATA
pARAMeteR
Min
tYp
MAX
unit
Logic High Input: VH
2.0
-
-
V
Logic Low Input: VL
-
-
0.8
V
Logic Input Current Consumption
-
-
0.01
mA
Data to Clock Set Up Time: tCS
50
-
-
ns
Data to Clock Hold Time: tCH
10
-
-
ns
Clock Pulse Width High: tCWH
50
-
-
ns
Clock Pulse Width Low: tCWL
50
-
-
ns
Clock to Load Enable Setup Time: tES
50
-
-
ns
Load Enable Pulse Width: tEW
50
-
-
ns
Rise Time: tR
-
10
-
ns
Fall Time: tF
-
10
-
ns
D15: MSB
D14
D8
D1
D7
D0: LSB
CLOCK
tCWL
ENABLE
OR
ENABLE
tCS
tCH
tCWH
tES
tEW
Figure 17: Serial Data Input Timing
Data Sheet - Rev 2.3
04/2011
13
ARA2000
application information
Transmit Enable / Disable
The ARA2000 includes two amplification stages that
each can be shut down through external control pins
Vg1 and Vg2 (pins 6 and 23, respectively.) By applying
a slightly positive bias of typically +1.0 Volts, the
amplifier is enabled. In order to disable the amplifier,
the control pin needs to be pulled to ground.
A practical way to implement the necessary control is
to use bias resistor networks similar to those shown
in the test circuit schematic (Figure 4.) Each network
includes a resistor shunted to ground that serves as
a pull-down to disable the amplifier when no control
voltage is applied. When a positive voltage is applied,
the network acts as a voltage divider that presents
the required +1.0 Volts to enable the amplifier. By
selecting different resistor values for the voltage
divider, the network can accommodate different control
voltage inputs.
The Vg1 and Vg2 pins may be connected together
directly, and controlled through a single resistor
network from a common control voltage.
Amplifier Bias Current
The Iset pins (7 and 22) 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.
Thermal Layout Considerations
The device package for the ARA2000 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 this slug 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.)
A PC board layout that optimizes the benefits of the
heat slug is shown in Figure 18. 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 a
sufficient heat sink. The recommended solder mask
outline is shown in Figure 19.
Figure 18: PC Board Layout
14
Data Sheet - Rev 2.3
04/2011
03/2011
ARA2000
Output Transformer
Matching the output of the ARA2000 to a 75 Ohm load
is accomplished using a 2:1 turns ratio transformer. In
addition to providing an impedance transformation, this
transformer provides the bias to the output amplifier
stage via the center tap.
The transformer also cancels even mode distortion
products and common mode signals, such as the
voltage transients that occur while enabling and
disabling the amplifiers. As a result, care must be
taken when selecting the transformer to be used at
the output. It must be capable of handling the RF and
DC power requirements without saturating the core,
and it must have adequate isolation and good phase
and amplitude balance. It also must operate over
the desired frequency and temperature range for the
intended application.
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.
Figure 19: Solder Mask Outline
Data Sheet - Rev 2.3
04/2011
15
ARA2000
PACKAGE OUTLINE
Figure 20: S12 Package Outline - 28 Pin SSOP with Heat Slug
16
Data Sheet - Rev 2.3
04/2011
ARA2000
COMPONENT PACKAGING
Volume quantities of the ARA2000 are supplied on
tape and reel. Each reel holds 3,500 pieces.
Figure 21: Reel Dimensions
Figure 22: Tape Dimensions
Data Sheet - Rev 2.3
04/2011
17
ARA2000
Notes
18
Data Sheet - Rev 2.3
04/2011
ARA2000
Notes
Data Sheet - Rev 2.3
04/2011
19
ARA2000
Notes
20
Data Sheet - Rev 2.3
04/2011
ARA2000
Ordering Information
oRdeR nuMBeR
teMpeRAtuRe
RAnGe
pAcKAGe
descRiption
ARA2000S12P1
-40 to 85 °C
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: [email protected]
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.
21
Data Sheet - Rev 2.3
04/2011