ARA1400
I
S12
CATV Reverse Amplifier with Step Attenuator
Advanced Product Information
Rev. 0
FEATURES
·
·
·
·
·
·
Low cost integrated monolithic GaAs
amplifier and step attenuator with output
disconnect switch.
Meets DOCSIS distortion requirements at
+60 dBmV
Frequency range: 5 100 MHz
Attenuation Range: 0 56 dB, variable in
4 dB steps
5 Volt operation
Low distortion & Low noise figure
APPLICATIONS
·
·
·
MCNS/DOCSIS Compliant Cable Modems
CATV Interactive Set-Top Box
Telephony over Cable Systems
S12
28 PIN SSOP PACKAGE
DESCRIPTION
The ARA1400IS12 is a GaAs IC designed to perform 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. It is capable of meeting the MCNS/DOCSIS harmonic distortion specifications while only requiring
a single polarity +5V supply. This part is a single ended design that does not require an output balun to
achieve 52 dBc 2
nd
harmonic
performance at +60 dBmV
ABSOLUTE MAXIMUM RATINGS
output levels. Both the input and
PARAMETER
output are matched to 75 ohms.
PARAMETER
The
precision
attenuator
V
DD
(P INS 4,12,17)
9
VD C
provides up to 56 dB of
attenuation in 4 dB increments.
0 to -3
VD C
V
RFIN
(P INS 10, 26)
The ARA1400IS12 is supplied in
5
VD C
ATT
IN
(3) ATT
OUT
(28)V
a 28-pin SSOP package featuring
a thermal heat slug on the bottom
2
VD C
V
ISET
(P INS 11, 27)
of package. Soldering this heat
RF Input Voltage (P INS 10, 26)*
+ 60
dB mV
slug to the ground plane of the PC
board ensures the lowest possible
Storage T mperature
e
- 55 to +200
°C
thermal resistance for the device
S olderi ng T mperature
e
260
°C
resulting in a long MTF. The
performance of the ARA1400IS12
S olderi ng Ti me
5
S ec
is rated over an industrial tem-
Operati ng C ase T mperature
e
-40 to + 85
°C
perature range of -40
°
to +85
° C.
ARA1400
I
S12
CATV REVERSE AMPLIFIER WITH STEP ATTENUATOR
Advanced Product Information Rev. 0
ELECTRICAL CHARACTERISTICS (TYPICAL) (V
DD
=5 V
DC
, T
C
=25
°C)
PA RA ME TE R
Gai n
1
MIN
30
1
TYP
32
0.75
-0.006
3.9
8.0
15.7
31.5
-57
-64
-
70
MA X
33
-
-
4.2
8.3
16.1
32.0
-52
-56
-
-
2.5
-24.6
-41.6
30
-
-15
-
-15
-10
1
V
DD
-
7
-
-2
95
130
20
1.23
0.5
6.5
-
UNIT
dB
dB
dB /°c
C OMME NTS
A t 0dB attenuati on
setti ng
5 to 100 MHz
Gai n Flatness
-
-
3.6
7.7
15.3
31.0
10 MHz
10 MHz
-
-
78
Gai n Vari ati on Over T mp
e
A ttenuati on Steps
1
4 dB
8 dB
16 dB
32 dB
2
dB
2
nd
Harmoni c D i storti on Level
3
rd
Harmoni c D i storti on Level
dB c
dB c
dB mV
dB mV
dB
dB mV
at +60 dB mV
at +60 dB mV
2
3
rd
Order Output Intercept P oi nt
1 dB Gai n C ompressi on P oi nt
Noi se Fi gure
Ouput Noi se P ower
A cti ve/No S i gnal/Mi n A ttn. S etti ng
A cti ve/No S i gnal/Max A ttn. S etti ng
S wi tch Isolati on at 45 MHz
Input Impedance
1
Input Return Loss
1
Output Impedance
1
Output Return Loss
1
Output Return Loss
1
Output S wi tch C ontrol Logi c
Output S wi tch C ontrol Impedance
V
D D 1
, V
D D 2
V
D D
D i gi tal
V S hutdown
I
DD1
I
DD2
I
D D
D i gi tal
P ower C onsumpti on
A ttenuator C ontrol Logi c
4
-
-
-
-
-
-
-
-
-
V IL
V IH
0
2.8
-
-
-
-1.5
70
105
12
-
V IL
V IH
0
2.7
-
1.7
-
-
35
75
-20
75
-20
-12
-
-
10K
5
5
-
81
121
14
1.08
-
-
5 K
A ny 3200 K Hz
bandwi dth from
5-42 MHz
D i fference i n output
si gnal level between
acti ve and standby
dB
ohm
dB
ohm
dB
dB
V
V
ohm
V
V
V
mA
mA
mA
W
Volts
ohm
Tx enabled
Tx di sabled
A ttenuator C ontrol Impedance
Notes:
1. As measured in ANADIGICS test fixture
2. At +60 dBmV output level into 75 ohm load
A
2