TEA5764UK-G NXP Semiconductors, TEA5764UK-G Datasheet - Page 16

• Manufacturer Part Number: TEA5764UK-G
• Description: Tuners FM RADIO WITH RDS
• Manufacturer: NXP Semiconductors

Specifications of TEA5764UK-G

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: TEA5764UK/N2,027

Philips Semiconductors
TEA5764UK_2
Product data sheet
8.22.1 Muting during RDS update
The algorithm will finish with the FRRFLAG being set and an interrupt is generated. After
this interrupt the TEA5764UK will not measure the IF count for a period of 15 ms. 15 ms
after completing a RDS jump, a measurement of the IF count will start and hence the IF
count result and the IFFLAG will be updated 30.6 ms after completing the algorithm. The
level measurement will start immediately after the tuning algorithm, so the LEVFLAG will
be updated 500 s after the algorithm. The state of the TEA5764UK can be checked by
reading registers INTFLAG, FRQCHKLSB, FRQCHKMSB, IFCHK and LEVCHK.
shows the possible states after an auto search,
RDS is updated.
An RDS update (AF jump) is always muted. There are two possibilities for leaving the
algorithm:
Table 5:
[1]
IFFLAG BLFLAG FRRFLAG Comment
0
0
0
0
1
1
1
1
•
•
The tuner jumps to an alternative frequency which is not valid (according to the
specified SSL limit and fixed IF counter limits) and jumps back, then it will
automatically unmute.
Or the tuner jumps to a valid alternative frequency and stays there. Now it does not
unmute. The microprocessor can unmute or it keeps the tuner muted and can check
for the presence of RDS data. The valid way to unmute is to apply a preset to the
current frequency (an IF count time of 15.6 ms is used at preset, which gives a more
accurate IF count result than the result obtained by the AF jump, where 2 ms is used).
This table is valid until 30.6 ms after an RDS update has completed. It shows the outcome of the flag
register when a read is done after pin INTX has gone LOW and on condition that only mask bit FRRMSK is
set.
0
0
1
1
0
0
1
1
RDS update truth table
0
1
0
1
0
1
0
1
Rev. 02 — 9 August 2005
if pin INTX is LOW and only IFMSK, FRRMSK and BLMSK were
set then this cannot occur
alternative frequency jump successful; radio is tuned to the
alternative frequency and stays muted
not a valid state
not a valid state
not a valid state
AF jump has occurred but the wanted channel fails the IF count;
the PLL will be set back to the old value
not a valid state
if pin INTX is LOW and only IFMSK, FRRMSK and BLMSK were
set then this cannot occur
[1]
Figure 5
is a flowchart showing how the
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
TEA5764UK
FM radio + RDS
Table 5
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