Z02215
Single Chip Modem with Integrated Controller, Data Pump, and AFE
48
Table 9. Selectable Configurations
Symbol Bits
Carrier
Frequency
Data Rate
(bps)
Rate
(baud)
Per
Constellation
1,2
Configuration
V.22 bis 2400
V.22 bis 1200
V.22 1200
V.23 1200/75
V.21
Modulation
QAM
Symbol Points
1200/2400
1200/2400
1200/2400
1700/420
2400
600
4
2
2
1
1
2
1
16
4
DPSK
DPSK
FSK
1200
600
1200
600
4
1200/75
300
1200/75
300
–
FSK
1080/1750
1200/2400
1170/2125
1700/437
–
Bell 212A
DPSK
FSK
1200
600
4
Bell 103
300
300
–
Bell 202/ Bell
FSK
1200/150
1200/150 1
–
202T 1200/150
Notes:
1. QAM is Quadrature Amplitude Modulation FSK is Frequency Shift Key
2. Tone is Single or Dual Tone (DTMF), TM is Trellis Modulation, DPSK is Dual Phase Shift Keying
Transmitted Data Spectrum
The transmitted data spectrum, with compromised equalization disabled, is
shaped in the baseband of the Finite Impulse Response (FIR) filter. Table 10
reflects the spectrum characteristics.
Table 10.Spectral Shaping
Mode
Carrier Freq
1200/2400
1200/2400
1200/2400
Spectral Power Shaping Function
V.22
square root 75% Raised Cosine at 600 baud
square root 75% Raised Cosine at 600 baud
square root 75% Raised Cosine at 600 baud
V.22bis
Bell 212A
Note: The carrier and the spectral shaping are selected automatically according to the Configuration.
Active Hybrid Circuit and Relay Driver
An active hybrid circuit is added to the Analog Front End (AFE) of the Z02215 to
improve the received signal quality level by 20dB and to improve the modem per-
formance. The on-chip active hybrid reduces system level costs by reducing the
PS001907-0904
Transmitted Data Spectrum
ZILOG [ ZILOG, INC. ]
