CMX644AD2 View Datasheet(PDF) - MX-COM Inc
Part Name
Description
MFG CO.
'CMX644AD2' PDF : 31 Pages View PDF
Bell 212A / V.22 Modem with Call Progress and DTMF
28
Receiver
Dynamic Range (VDD = 5.0V)
Carrier Detect
Threshold: Will Decode
Threshold: Will Not Decode
Hysteresis
Response Time (Delay)
De-Response Time (Hold)
Answer Tone Detector
Threshold: Will Decode
Threshold: Will Not Decode
Response Time (Delay)
De-Response Time (Hold)
Decode Bandwidth
Must Decode
Must Not Decode
Call Progress Detector
Effective Bandwidth
Threshold: Will Decode
Threshold: Will Not Decode
Response Time (Delay)
De-Response Time (Hold)
Programmable Gain Blocks
Rx Gain Block
Nominal Range
(Step Size: see Register Description)
Step Accuracy
Tx Gain Block
Nominal Range
Step Size
Step Accuracy
Notes
1, 6
1, 6
7
1, 6
1, 6
9
1, 6
1, 6
Min.
-48
-48
2.0
300/400
-48
-4.70
-0.5
-5.6
-0.2
CMX644A Preliminary Information
Typ.
Max.
Units
45
dB
-43
dBm
dBm
2.0
dB
20
50
ms
20
50
ms
-43
dBm
dBm
20
50
ms
20
50
ms
%
6.0
%
620
Hz
-43
dBm
dBm
20
50
ms
20
50
ms
+6.58
dB
+0.5
dB
0.0
dB
0.4
dB
+0.2
dB
Notes:
1. At VDD = 5.0V only. Signal levels or currents are proportional to VDD.
2. Not including any current drawn from the modem pins by external circuitry.
3. Timing for an external input to the CLOCK/XTAL pin.
4. Tx Gain Block set to 0dB and measured with a pure tone or DTMF tone pair, without equalization.
5. Excluding RD, RT and XTAL/CLOCK pins.
6. Rx Gain Block nominally set to 0dB but adjusted if necessary for component tolerances. Measurement
point for threshold levels is prior to receive input amplifier circuit (point A on Figure 11), with external
components setting gain to 9dB. Detector levels measured with a pure tone.
7. Hysteresis may be increased, if required, by adding one step (increasing the gain of) to the Rx Gain Block
when a signal is detected and by removing this step when the signal is no longer detected.
8. Measured with a 511-bit pseudorandom sequence.
9. Depending on the setting of the CPBW SELECT bit in the RX PSK MODE Register
2000 MX-COM, Inc.
www.mxcom.com tel: 800 638 5577 336 744 5050 fax: 336 744 5054
Doc. # 20480197.006
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies.
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