mt88e43 Zarlink Semiconductor, mt88e43 Datasheet - Page 23

• Manufacturer Part Number: mt88e43
• Description: Extended Voltage Calling Number Identification Circuit 2
• Manufacturer: Zarlink Semiconductor

Data Sheet
Notes
1) In a CPE where AC power is not available, the designer may choose to switch over to line power when the CPE goes off-hook and
2) Non-FSK signals such as CAS, speech and DTMF tones are in the same frequency band as FSK. They will be demodulated and
3) FSKen may be set high as soon as the CPE has finished sending the acknowledgment signal ACK. TR-NWT-000575 specifies that
4) FSKen should be set low when CD has become inactive.
5) In an unsuccessful attempt where the end office does not send the FSK signal, the CPE should unmute the handset and enable the
6) SR-TSV-002476 states that it is desirable that the CPE have an on/off switch for the CAS detector. See SW1 in Figure 4.
7) The total recognition time is t
8) The total tone absent time is t
StD
use battery power while on-hook. The CPE should also be CID (on-hook) capable because TR-NWT-000575 specifies that CIDCW
will be offered only to lines which subscribe to CID.
give false data. The FSKen pin should be set low to disable the FSK demodulator when FSK is not expected.
ACK = DTMF D for non-ADSI CPE, A for ADSI CPE.
keypad after this interval.
to section “Dual Tone Detection Guard Time” on page 58 for details). V
to section “Dual Tone Detection Guard Time” on page 58 for details). V
TIP/RING
:
OSCout
(Note 6)
FSKen
PWDN
DCLK
DATA
St/GT
ESt
CD
DR
Figure 20 - Input and Output Timing for Bellcore Off-hook Data Transmission, e.g., CIDCW
Note 1
CPE goes off-hook
Note 2
t
t
DP
t
t
PU
GP
REC
REC
ABS
Note 7
= t
= t
CAS
GP
A
GA
+ t
Note 8
+ t
DP
DA
, where t
, where t
CPE mutes handset & disables keypad
B
t
V
DA
TGt
t
t
ABS
GA
GP
GA
CPE sends
is the tone present guard time and t
is the tone absent guard time and t
ACK
C
Note 3
Note 5
t
CP
D
TGt
TGt
is the comparator threshold (refer to Figure 4).
is the comparator threshold (refer to Figure 4).
Mark
E
Packet
Data
Data
DP
DA
F
is the tone present detect time (refer
is the tone absent detect time (refer
CPE unmutes handset
and enables keypad
Note 4
G
A = 75-85ms
B = 0-100ms
C = 55-65ms
D = 0-500ms
E = 58-75ms
F = feature specific
G
t
CA
50ms
MT88E43
5-75