DM336P Davicom Semiconductor Incorporated, DM336P Datasheet - Page 29

• Manufacturer Part Number: DM336P
• Manufacturer: Davicom Semiconductor Incorporated

• Chip 3 : DM6380 Analog Front End (AFE) Description
DM6380 Description
The DM6380 is a single chip Analog Front End (AFE)
designed to implement voice grade modem up to
33600bps. It is used as a portion of a complete
modem device set. The AFE converts the analog
signal into digital form and transfers the digital data to
the DSP through the serial port. All the clock
information needed in a modem device is also
generated in this device. The differential analog
outputs are provided to acquire the maximum output
signal level. An audio monitor whose volume is
programmable is built in to monitor the on-line signal.
Inside the device, a 16-bit ADC and a 16-bit DAC with
over-sampling and noise-shaping techniques is
implemented to maximize performance for high speed
modem. It offers wide-band transmit and receive
filters so that the voice band signal is transmitted or
received without amplitude distortion and with
DM6380 Block Diagram
Final
Version: DM336P-DS-F02
August 15, 2000
RxDCLK
RxSCLK
SCLK
D O R
D O T
RFS
TFS
DIR
DIT
Reconstruction
Interface
Digital
Digital
Filter
Rx Clock
V.34 Integrated Data/ Fax/Voice/Speakerphone Modem Device Set
System
Tx Filter &
Rx Filter &
Registers
Control
D A C
A D C
Tx Clock
System
minimum group delay. In order to support the multi-
mode modem standards, such as V.34, V.32bis, V.32,
V.22bis, V.22, V.23, V.21, Bell 212A, Bell 103, V.17,
V.29, V.27ter, the programmable baud and data rate
clock generators are provided. For the asymmetric
channel usage, the transmit and receive clock
generators are independent. In order to provide the
echo-cancel capability, the receive clock is
synchronized with the transmit clock and the best
receive timing sample is reconstructed by a
reconstruction filter. Transmit Digital Phase Lock
Loop (DPLL) is self-tuning to provide the master,
slave or free-running mode for the data terminal
interface. A software programmable receive DPLL
that is step-controllable by the host DSP is
implemented to get the best samples for the relevant
signal processing.
Voltage Reference
0/-6 dB
Attenuator
Audio Amplifier
Divider
LPF &
Power-on
Detector
RxIN
TxSCLK*2
TxDCLK
ExtCLK
CLKIN
TxA1
TxA2
V
V
V
SPKR
R E F P
C M
R E F N
DM336P
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