TEA5764UK-G NXP Semiconductors, TEA5764UK-G Datasheet - Page 14

• 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
8.21.1 Search mode
8.21.2 Preset mode
Search mode is initiated by setting bit SM in byte FRQSETMSB to logic 1. The search
direction is set by bit SUD; SUD = 0 (search down), bit SUD = 1 (search up). The tuner
starts searching at the frequency set in bytes FRQSETLSB and FRQSETMSB. The
Search Stop Level (SSL) bits define the field strength level at which a desired channel is
detected. The tuner will stop on a channel with a field strength equal to or higher than this
reference level and then checks the IF frequency; when both are valid, the search stops
(Note that this depends on bit AHLSI described in
IF-count fails, the search continues. If no channels are found, the TEA5764UK stops
searching when it has reached the band limit, setting the BLFLAG HIGH. A search always
stops when the FRRFLAG is set and on the occurrence of a hardware interrupt, this
procedure is shown in
The search algorithm can stop at a frequency that is offset from the IF by up to a
maximum of 12 kHz. The maximum offset can be limited to 8 kHz by applying a preset.
For optimum tuning, it is recommended that a preset is applied after a search and when
the found frequency has an offset that is above 8 kHz.
After this interrupt the TEA5764UK will not update the tuner registers for a period of 15
ms. The state of the TEA5764UK can be checked by reading the bytes of INTFLAG,
FRQCHKMSB, FRQCHKLSB, TNCTRL1 and TNCTRL2.
states of these registers after an auto search.
Table 4:
[1]
A preset occurs by setting bit SM to logic 0 and writing a frequency to byte FRQSETMSB.
The tuner jumps to the selected frequency and sets the FRRFLAG when it is ready.
After this interrupt the TEA5764UK will not update the tuner registers for a period of
15 ms. The state of the TEA5764UK can be checked by reading registers: INTFLAG,
FRQCHKLSB, FRQCHKMSB, TNCTRL1 and TNCTRL2.
states after a preset.
IFFLAG BLFLAG FRRFLAG Comment
0
0
0
0
1
1
1
1
This table is valid until 30.6 ms after the tuning cycle has completed. It shows the outcome of the flag
register when a read is done after pin INTX goes LOW on condition that no mask bit other than FRRMSK is
set.
0
0
1
1
0
0
1
1
Tuner truth table
0
1
0
1
0
1
0
1
Figure
Rev. 02 — 9 August 2005
[1]
3.
if pin INTX has gone LOW and only IFMSK, FRRMSK and
BLMSK were set then this cannot occur
channel found during search / preset; FRRMSK set
not a valid state
a valid channel found and the band limit has been reached
during a search; BLMSK or FRRMSK set
not a valid state
a preset or search has occurred but the wanted channel has a
valid RSSI level but fails the IF count when AHLSI was set to
logic 1; HLSI must be toggled and a new PLL value must be
programmed; FRRMSK set
not a valid state
band limit is reached during search; no valid channel found;
BLMSK or FRRMSK set
Figure
3). If the level check or the
Table 4
Table 4
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
TEA5764UK
shows the possible
shows the possible
FM radio + RDS
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