Low Power V.32 bis Modem
CMX869
XTAL/CLOCK Input
Notes
Min.
Typ.
Max.
Units
(timings for an external clock input)
'High' Pulse Width
'Low' Pulse Width
60
60
-
-
-
-
ns
ns
Transmit Output Level
Modem and Single Tone modes
DTMF mode, Low Group tones
DTMF: level of High Group tones wrt Low Group
Tx output buffer gain control accuracy
Notes
Min.
-1.5
0.5
+1.0
-0.25
Typ.
Max.
0.5
2.5
+3.0
+0.25
Units
dBm
dBm
dB
5
5
5
5
-0.5
1.5
+2.0
-
DB
Tx output impedance (TXA or TXAN)
-
6.0
-
Ω
Notes:
5. Measured between TXA and TXAN pins with Tx Level Control gain set to 0dB, 1.2kΩ load
between TXA and TXAN, at AV = 3.3V (levels are proportional to AV - see section
DD
DD
4.3). Level measurements for all modem modes are performed with random transmitted
data and without any guard tone. 0dBm = 775mVrms. DTMF twist set to +2.0dB.
0
-10
Bell 202
-20
-30
dBm
-40
-50
-60
-70
10
100
1000
Hz
10000
100000
Figure 12 Maximum Out of Band Tx Line Energy Limits (see note 6)
Notes:
6. Measured on the 2 or 4-wire line using the line interface circuits described in section 4.3
with the Tx line signal level set to -10dBm for any modem mode or single tones, -6dBm
and -8dBm for DTMF tones. Excludes any distortion due to external components such as
the line coupling transformer.
© 2004 CML Microsystems Plc
41
D/869/4
CMLMICRO [ CML MICROCIRCUITS ]
