DS32508N+ Maxim Integrated Products, DS32508N+ Datasheet - Page 30

• Manufacturer Part Number: DS32508N+
• Description: IC LIU DS3/E3/STS-1 484-BGA
• Manufacturer: Maxim Integrated Products
• Type: Line Interface Units (LIUs)r

Specifications of DS32508N+

• Protocol: IEEE 1149.1
• Voltage - Supply: 1.8V, 3.3V
• Mounting Type: Surface Mount
• Package / Case: 484-BGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Number Of Drivers/receivers: -

8.3 Receiver
8.3.1 Interfacing to the Line
The receiver can be transformer-coupled or capacitor-coupled to the line. Typically, the receiver interfaces to the
incoming coaxial cable (75 Ω ) through a 1:1 isolation transformer. The receive line termination can be internal to the
device, external to the device, or a combination of both.
the internal termination is enabled (LIU.CR2:RTRE = 1) and no external termination resistors are used.
shows the arrangement of the transformer and external termination resistors when the internal termination is
disabled (LIU.CR2:RTRE = 0). The internal termination resistor value is specified in LIU.CR2:RRESADJ[3:0].
8-7
transformers. The receiver expects the incoming signal to be in B3ZS- or HDB3-coded AMI format.
Table 8-7. Transformer Characteristics
Table 8-8. Recommended Transformers
Note: Table subject to change. Multiport transformers are also available. Contact the manufacturers for details at www.pulseeng.com and
www.haloelectronics.com.
8.3.2
The receiver can be used in monitoring applications that typically have series resistors with a resistive loss of
approximately 20dB. When the
compensate for this resistive loss by applying 14dB of additional flat gain to the incoming signal before sending the
signal to the AGC/equalizer block (an additional 6dB of flat gain is applied in the AGC circuitry for a total gain of
20dB). When the preamp is enabled the receiver automatically determines whether or not to make use of the
preamp’s additional gain. Status bit LIU.SR:RPAS indicates whether or not the preamp is in use. A change of state
of LIU.SR:RPAS can cause an interrupt if enabled by LIU.SRIE:RPASIE.
8.3.3 Automatic Gain Control (AGC) and Adaptive Equalizer
The AGC circuitry applies flat (frequency independent) gain to the incoming signal to compensate for flat losses in
the transmission channel and variations in transmission power. Since the incoming signal also experiences
frequency-dependent losses as it passes through the coaxial cable, the adaptive equalizer circuitry applies
frequency-dependent gain to offset line losses and restore the signal. The AGC/equalizer circuitry automatically
adapts to coaxial cable losses from 0 to 22dB, which translates into 0 to 457 meters (1500 feet) of coaxial cable
Turns Ratio
Bandwidth 75 Ω
Primary Inductance
Leakage Inductance
Interwinding Capacitance
Isolation Voltage
MANUFACTURER
Pulse Engineering
Pulse Engineering
Pulse Engineering
Pulse Engineering
Pulse Engineering
Pulse Engineering
Pulse Engineering
Halo Electronics
Halo Electronics
Halo Electronics
Halo Electronics
and
Optional Preamp
PARAMETER
Table 8-8
specify the required characteristics of the transformer and provide a list of recommended
TG01-0406NS
TG01-0456NS -40°C to +85°C
TD01-0406NS
TD01-0456NE -40°C to +85°C
PE-65967
PE-65966
TX3025
TX3036
TX3047
TX3051
T3001
PART
RMON
0.200MHz to 340MHz (typ)
pin is high or the LIU.CR2:RMON configuration bit is set, the receiver can
1500V
0.12 μ H (max)
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
TEMP RANGE
10pF (max)
0°C to +70°C
40 μ H (min)
0°C to +70°C
0°C to +70°C
0°C to +70°C
1:1 ± 2%
VALUE
RMS
(min)
30 of 130
Figure 4-1
6 SMT SMD/A
6 SMT SMD/A
6 SMT LS-1/E
6 SMT LS-2/E
6 THT LC-1/E
SCHEMATIC
16 SMT BH/3
32 SMT YB/1
6 DIP DIP/A
6 DIP DIP/A
PACKAGE/
24 SMT
48 SMT
PIN-
shows the arrangement of the transformer when
(μH) (min)
PRIMARY
OCL
100
100
100
40
40
40
60
40
40
45
45
DS32506/DS32508/DS32512
(max)
0.120
0.110
0.150
0.120
(μH)
0.10
0.10
0.11
0.10
0.10
0.12
0.12
L
L
BANDWIDTH
75Ω (MHz)
1500
1500
1500
1500
1500
1500
1500
1500
1500
1500
1500
Figure 4-2
Table