MAX3507EGI Maxim, MAX3507EGI Datasheet - Page 9

• Manufacturer Part Number: MAX3507EGI
• Description: Upstream CATV Amplifier with On-Chip Anti-Alias Filter
• Manufacturer: Maxim

Figure 1. Serial Interface Timing Diagram
Table 2. Chip-State Control Bits
former must have adequate bandwidth to cover the
intended application. Note that most RF transformers
specify bandwidth with a 50Ω source on the primary
and a matching resistance on the secondary winding.
Operating in a 75Ω system will tend to shift the low-fre-
quency edge of the transformer bandwidth specifica-
tion up by a factor of 1.5, due to primary inductance.
Keep this in mind when specifying a transformer.
Bias to the output stage is provided through the center
tap on the transformer primary. This greatly diminishes
Typical gain at T
SHDN
0
1
1
1
1
1
1
1
1
1
A
TXEN
= +25°C and V
X
0
1
1
1
1
1
1
1
1
_______________________________________________________________________________________
D7
X
X
1
0
0
0
0
1
1
1
D6
CC
X
X
X
X
0
1
1
1
1
1
= +5V.
A
D5
X
X
X
X
1
0
1
0
1
1
D7
D4
X
X
X
X
1
1
0
1
0
1
A. t
B. t
C. t
D. t
Upstream CATV Amplifier with
D6
G
SENS
SDAS
SDAH
SCLKL
D3
X
X
X
X
0
0
1
0
1
1
D5
D2
X
X
X
X
0
0
1
1
1
1
B
D4
D1
X
X
X
X
0
0
1
1
1
0
On-Chip Anti-Alias Filter
E. t
F. t
G. t
SCLKH
SENH
DATAH
the on/off transients present at the output when switch-
ing between transmit and transmit disable modes.
Commercially available transformers typically have
adequate balance between half-windings to achieve
substantial transient cancellation.
Finally, keep in mind that transformer core inductance
varies proportionally with temperature. If the application
requires low temperature extremes (less than 0°C),
adequate primary inductance must be present to sus-
tain low-frequency output capability as temperatures
D3
D0
C
X
X
X
X
0
0
0
0
0
1
/t
DATAL
D2
GAIN STATE
(DECIMAL)
110
110
125
D
48
80
86
D1
—
—
—
—
E
D0
F
GAIN
11.69
-22.6
-6.29
(dB)
8.68
23.7
31.0
—
—
—
—
Transmit Disable Mode
Transmit Enable Mode,
Transmit Enable Mode,
High Power
Low Noise
Shutdown
STATES
—
—
—
—
—
—
9