DS21Q58L+ Maxim Integrated Products, DS21Q58L+ Datasheet - Page 49

• Manufacturer Part Number: DS21Q58L+
• Description: IC TXRX E1 QUAD 3.3V 100LQFP
• Manufacturer: Maxim Integrated Products

Specifications of DS21Q58L+

• Function: Transceiver
• Interface: E1
• Number Of Circuits: 4
• Voltage - Supply: 3.14 V ~ 3.47 V
• Current - Supply: 230mA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 100-LQFP
• Includes: AIS Alarms Detector and Generator, Loopback Functions, PRBS Generator / Detector, Remote Detector and Generator
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power (watts): -

21.3 Transmit Waveshaping and Line Driving
The DS21Q58 uses a set of laser-trimmed delay lines and a precision digital-to-analog converter (DAC) to create
the waveforms that are transmitted onto the E1 line. The waveforms meet the ITU G.703 specifications
(Figure
the line interface control register (LICR). The DS21Q58 can be set up in a number of various configurations
depending on the application
Table 21-2. Line Build-Out Select in LICR
*N.M. = Not meaningful (return loss value too low for significance)
**Refer to Application Note 336: Transparent Operation on T1, E1 Framers and Transceivers for details on E1 line interface design.
Because of the nature of the transmitter’s design, very little jitter (less than 0.005UI
100kHz) is added to the jitter present on TCLK (or source used for transmit clock). Also, the waveform created is
independent of the duty cycle of TCLK. The device’s transmitter couples to the E1-transmit shielded twisted pair or
coax through a 1:2 step-up transformer, as shown in
the transformer used must meet the specifications listed in
current limiter that prevents more than 50mA (RMS) from being sourced in a 1W load.
Table 21-3. Transformer Specifications
Figure 21-2. External Analog Connections (Basic Configuration)
L2
0
0
0
0
1
1
Intertwining Capacitance
L1
E1 TRANSMIT
0
0
1
1
0
0
21-4). The user selects which waveform is to be generated by properly programming the L2/L1/L0 bits in
Leakage Inductance
Primary Inductance
E1 RECEIVE
SPECIFICATION
DC Resistance
Turns Ratio
L0
0
1
0
1
0
1
LINE
LINE
75W normal
120W normal
75W with protection resistors
120W with protection resistors
75W with high return loss
120W with high return loss
APPLICATION
(Table
21-2).
1:1 (receive) and 1:2 (transmit) ±3%
2 : 1
1 : 1
(
NONPOLARIZED
RECOMMENDED VALUE
0.1mF
Rr
600mH minimum
1.0mH maximum
0.47mF
40pF maximum
1.2W maximum
TRANSFORMER
49 of 74
Figure
Rr
1:2 step-up
1:2 step-up
1:2 step-up
1:2 step-up
1:2 step-up
1:2 step-up
)
21-2. For the devices to create the proper waveforms,
Table
RTIP
TTIP
TRING
RRING
1/4
21-3. The line driver in the device contains a
DS21Q58
MCLK
RETURN LOSS
DVDD
RVDD
DVSS
TVDD
RVSS
TVSS
21dB
21dB
N.M.
N.M.
N.M.
N.M.
0.01mF
P-P
0.1mF
0.1mF
0.1mF
2.048MHz
*
broadband from 10Hz to
+3.3V
Rt (W)
11.6
2.5
2.5
6.2
0
0
**