INDUSTRIAL TEMPERATURE RANGE
IDT821068 OCTAL PROGRAMMABLE PCM CODEC
2
DESCRIPTION
The IDT821068 is a feature rich, single-chip, programmable 8
channel PCM CODEC with on-chip filters. Besides the A-Law/
μ
-Law
companding and linear coding/decoding (16-bit 2’s complement),
IDT821068 provides 2 programmable Tone generators per channel
(which can also generate ring signals), 1 FSK generator, 1 program-
mable Teletax Signal generator and 2 programmable chopper clocks
for SLIC.
The digital filters in IDT821068 provide the necessary transmit and
receive filtering for voice telephone circuit to interface with time-division
multiplexed systems. An integrated programmable DSP realizes AC
Impedance Matching, Transhybrid Balance, Frequency Response
Correction and Gain Setting functions. The IDT821068 supports 2
PCM buses with programmable sampling edge, that allows an extra
delay of up to 7 clocks. Once the delay is determined, it is effective to
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IDT821068
128 PIN PQFP
PIN CONFIGURATIONS
all eight channels of IDT821068. The device also provides 7 signaling
pins to SLIC on per channel basis.
The IDT821068 provides 2 programming interfaces:
Microprocessor Interface (MPI) and General Control Interface (GCI),
which is also known as ISDN Oriented Module (IOM
-2). For both
MPI and GCI programming, the device supports both compressed
and linear data format.
The device also offers strong test capability with several analog/
digital loopbacks and level metering function. It brings convenience to
system maintenance and diagnosis.
A unique feature of ‘Hardware Ring Trip’ is implemented in
IDT821068. When off-hook signal is detected, IDT821068 can reverse
an output pin to stop ringing immediately.
The IDT821068 can be used in digital telecommunication
applications such as Central Office Switch, PBX, DLC and Integrated
Access Device (IAD), i.e. VoIP and VoDSL.
IOM
-2 is a registered trademark of Siemens AG.
SB2_8
SO1_8
SO2_8
SO3_8
GND78
GNDDP
NC
CHCLK1
CHCLK2
VDDDP
MCLK
BCLK/DCL
FS/FSC
NC
TSX2
DX2
DR2
TSX1
DX1/DU
DR1/DD
NC
GND34
SO3_4
SO2_4
SO1_4
SB2_4
SB2_5
SO1_5
SO2_5
SO3_5
GND56
MPI
CS
CCLK/TS
CI/DOUBLE
CO
INT
NC
NC
NC
NC
NC
NC
NC
NC
RESET
NC
GND12
SO3_1
SO2_1
SO1_1
SB2_1