PCD3316T NXP Semiconductors, PCD3316T Datasheet - Page 23

• Manufacturer Part Number: PCD3316T
• Manufacturer: NXP Semiconductors

Specifications of PCD3316T

• Process Technology: CMOS
• Operating Frequency (max): 3580kHz
• Mounting: Surface Mount
• Lead Free Status / Rohs Status: Supplier Unconfirmed

Philips Semiconductors
11. Test information
9397 750 04824
Product specification
a.
Fig 16. Application diagrams.
telephone
line
Attenuation networks.
a/b
b/a
Attenuation networks to connect the polarity and FSK inputs to
the telephone line.
(250 V)
(250 V)
2.2 F
2.2 F
1 nF
1 nF
11.1 Application note on Customer Premises Equipment (CPE) testing
100 k
100 k
820 k
820 k
100 k
Under certain circumstances, some external CIDCW test equipment may generate
incorrect pulses after the ringing signal becomes inactive. These pulses may cause
the FSK detector of the PCD3316 to respond. Note that this is by no means an
incorrect behaviour of the PCD3316 chip, but a correct detection of incorrect test
stimuli. However, if not known, it may lead to confusing results during testing of the
CPE.
To avoid the issue described above, following work-around can be used:
1. Disable the FSK detection of PCD3316, before and during the ringing signal
2. Switch on the FSK detection only after a certain period, e.g. 100 ms after the
3. When the first FSK data is detected, e.g ‘55H’ (possible part of channel seizure),
detection.
ringing signal goes inactive.
switch off the FSK detection and on again. This will force the FSK detector to
resynchronize and detect the normal FSK data correctly. It may be necessary to
repeat this sequence a number of times to ensure that the data detected really
comes from the channel seizure. Thus, it is recommended to wait for a multiple
number of bytes ‘55H’ to be detected to validate a correct channel seizure.
100 k
FSKIN
FSKIN
POL0
POL1
11 March 1999
11
10
14
15
PCD3316
MGK729
ook, halfpage
b.
120 k
1.8 nF
High-pass filter.
High-pass filter (cut-off
frequency
performance of CAS detection.
100 nF
CASIN
© Philips Electronics N.V. 1999. All rights reserved.
1 kHz) to improve
13
PCD3316
CIDCW receiver
PCD3316
MBH996
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