CS61304A Cirrus Logic, Inc., CS61304A Datasheet - Page 8

• Manufacturer Part Number: CS61304A
• Description: T1-E1 Line Interface Unit for CPE-ISDN PRI
• Manufacturer: Cirrus Logic, Inc.

THEORY OF OPERATION
Key Enhancements of the CS61304A Relative
to the LXT304A
Introduction to Operating Modes
The CS61304A supports three operating modes
which are selected by the level of the MODE pin
as shown in Tables 1 and 2, Figure 7, and Figures
A1-A3 of the Applications section.
The modes are Hardware Mode, Extended Hard-
ware Mode, and Host Mode. In Hardware and
Extended Hardware Modes, discrete pins are used
to configure and monitor the device. The Ex-
tended Hardware Mode provides a parallel chip
select input which latches the control inputs al-
lowing individual ICs to be configured using a
common set of control lines. In the Host Mode,
an external processor monitors and configures the
device through a serial interface. There are thir-
teen multi-function pins whose functionality is
determined by the operating mode. (see Table 2).
8
12.5% Lower Power Consumption,
50 mA
limiting for E1 (per OFTEL OTR-001),
Optional AMI, B8ZS, HDB3 encoder/de-
coder or external line coding support,
Receiver AIS (unframed all ones) detection,
Improved receiver Loss of Signal handling
(LOS set at power-up, reset upon receipt of
3 ones in 32 bit periods with no more than
15 consecutive zeros),
Transmitter TTIP and TRING outputs are
forced low when TCLK is static,
RMS
transmitter short-circuit current
RECEIVER/DPM
TRANSMITTER
Performance
Detection
FUNCTION
CONTROL
Monitor
Control
Method
MODE
Coding
Driver
Table 1. Differences Between Operating Modes
Level
Line
AIS
Pin
Table 2. Pin Definitions
PIN HARDWARE
Hardware
11
17
18
18
23
24
25
26
27
28
3
4
6
7
External
Control
<0.2 V
Mode
Pins
Yes
No
RLOOP
MRING
LLOOP
RNEG
RPOS
TPOS
TNEG
LEN0
LEN1
LEN2
TAOS
MTIP
DPM
-
Control Pins
AMI, B8ZS,
with Parallel
Chip Select
Floating or
Hardware
Extended
or HDB3
Internal-
Mode
2.5 V
HARDWARE
EXTENDED
Yes
No
RCODE
CS61304A
TCODE
RLOOP
LLOOP
MODE
TDATA
RDATA
TAOS
LEN0
LEN1
LEN2
BPV
PCS
AIS
-
>(RV+)-0.2
DS156PP2
Interface
External
Serial
Mode
Host
MRING
Yes
No
RNEG
RPOS
HOST
TPOS
TNEG
SCLK
CLKE
MTIP
V
DPM
SDO
SDI
INT
CS
-