MT88E45
Data Sheet
In Figure 55, tDP is the delay from the start of CAS to EST responding, tDA is the delay from the end of CAS to EST
responding. The total delay from the start of CAS to STD responding is tREC=tDP+tGP. The total delay from the end of
CAS to STD responding is tABS=tDA+tGA.
Parameter
North America: Bellcorea
Europe: ETSIb
1300 Hz +/- 1.5%
2100 Hz +/- 1.5%
UK: BTc
Mark (Logical 1) Frequency
Space (Logical 0) Frequency
Received Signal Level
1200 Hz +/- 1%
2200 Hz +/- 1%
-4.23 to -36.20 dBm
(476 to 12 mVrms)d
-5.78 to -33.78 dBme
-5.78 to -37.78 dBm
(-8 to -40 dBV)
(-8 to -36 dBV)f,g
Signal Reject Level
-48.24 dBm (3mVrms) for
On-hook No Ring Signalling
such as VMWI
On-hook only:
-47.78 dBm
(-50dBV)
Transmission Rate
1200 baud +/- 1%
-6 to +10 dB
1200 baud +/- 1%
-6 to +6 dB
Twist (VMARK/VSPACE
)
Signal to Noise Ratio
Single Tone (f):
-18 dB (f<=60Hz)
>= 25 dB
>= 20 dB
(300 to 3400 Hz)
(300 to 3400 Hz)
-12 dB (60<f<=120Hz)
-6 dB (120<f<=200Hz)
+25 dB (200<f<3200Hz)
+6 dB (f>=3200Hz)
Tip/Ring Op-Amp (GS1) Gain
Vdd = 5V +/- 10%
0 dB
-2 dBh
0 dB
Tip/Ring Op-Amp (GS1) Gain
Vdd = 3V +/- 10%
-3.5 dB
-5.5 dBi
-3.5 dB
a. ANSI/TIA/EIA-716 and TIA/EIA-777. Bellcore has agreed to the values and will synchronize its requirements.
b. ETS 300 778-1 (On-hook) Sep 97, ETS 300 778-2 (Off-hook) Jan 98.
c. SIN 227 Issue 3 Nov 97, SIN242 Issue 2 Nov 96.
d. North American on-hook signalling range. The off-hook range is inside the on-hook range: 190mVrms to 12mVrms.
e. dBm - Decibels above or below a reference power of 1 mW into 600 ohms. 0 dBm = 0.7746 Vrms
f. dBV - Decibels above or below a reference voltage of 1 Vrms. 0 dBV = 1 Vrms.
g. ETSI on-hook signalling range. The off-Hook signalling levels are inside this range: -8.78 to -30.78 dBm (-11 to -33 dBV).
h. The 5V ETSI Tip/Ring op-amp gain can be 0 dB if there is no FSK reject level requirement.
i. The 3V ETSI Tip/Ring op-amp gain can be -3.5dB if there is no FSK reject level requirement.
Table 4 - FSK Signal Characteristics
FSK Demodulation
The FSK characteristics are shown in Table 4. In North America, TIA (Telecommunications Industry Association)
also sets standards. The Type 1 Caller ID CPE standard is ANSI/TIA/EIA-716. The Type 2 standard is TIA/EIA-777.
The North American FSK characteristics in Table 4 are from ANSI/TIA/EIA-716. They differ from those Bellcore
published in SR-TSV-002476 and SR-3004. Bellcore is represented in TR41.3.1 and will synchronize to the TIA
requirements in its future documents.
The TIA Type 1 standard includes an FSK reject level:
•
•
if data is not preceded by ringing (e.g., VMWI), FSK signals below 3mVrms (-48.24 dBm) shall be rejected
if data is preceded by ringing, FSK detection may be extended below 3mVrms
The MT88E45B is compliant with the Bellcore/TIA, ETSI and BT requirements with the Tip/Ring op-amp gains in
Table 4. In Europe if the country specific FSK requirements do not incorporate ETSI’s FSK reject level then the
Tip/Ring op-amp gain can also be 0 dB at 5 V and -3.5 dB at 3 V to meet the ETSI minimum CAS level for on-hook
signalling (-40 dBV).
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Zarlink Semiconductor Inc.
ZARLINK [ ZARLINK SEMICONDUCTOR INC ]
