Agere Systems DSP1648C
Host-Based Controller V.92 Modem Chip Set
Product Brief
September 2001
Integrated PCI Interface
Functional Description (continued)
The DSP1648C features a ROM-coded DSP1600 core
combined with the control and communications logic
required to implement a modem data pump. The
DSP1648 incorporates a PCI interface which supports
two full-duplex bus master streams for greater access
to host system resources. One PCI stream can be
switched between the audio codec interface or the DSP
core. The second full-duplex stream supports 4-word
block transfers between system and DSP core. 3.3 V
and 5 V signaling systems are supported for PCI bus
buffers. The device supply must come from a 3.3 V PCI
supply, vaux, or a regulated 3.3 V supply.
Changes from DSP1648 (Mars 3)
DSP1648C is a digital IC that provides the engine for
various modem standards. DSP1648C uses existing
DSP1648 specifications and functionality with some
enhancements. The following is a list of the new fea-
tures:
■ Support for V.92 and V.44:
— Fast connect
— Modem on hold
— PCM upstream
— Improved data compression
I/O Voltage Considerations
■ Additional on-chip RAM for V.92 support.
■ Additional PCI power management for future WHQL
requirements.
The system supply voltage requirement is
3.3 V ± 0.3 Vdc. This device also employs a 5 V
tolerant buffer topology. To support this 5 V tolerant I/O,
the VIO pin (pin 93) is provided as an indicator to the
device of the signaling voltage being used on the bus.
■ Lower power dissipation.
AGERE SYSTEMS
LUCENT TECHNOLOGIES
DSP1648C HOST-BASED CONTROLLER MODEM CHIP SET
U-DAA
CSP1035A (LINE-POWERED)
ROM CODED
DSP1648C
LINE
UNIVERSAL
DAA
REMAINING
COMPONENTS
FOR
CODEC
HOST
PROCESSOR
TELEPHONE
LINE
U-DAA
PCI
100-PIN
TQFP
48-PIN TQFP
0670 (F) d
Figure 2. Agere Systems DSP1648C Host-Based Controller Modem Chip Set Block Diagram
without Audio Codec
3
Agere Systems Inc.
AGERE [ AGERE SYSTEMS ]
