tea5766uk NXP Semiconductors, tea5766uk Datasheet - Page 9

• Manufacturer Part Number: tea5766uk
• Description: Tea5766uk Stereo Fm Radio + Rds
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TEA5766UK_1
Product data sheet
7.12.2 Hard mute
7.12.3 Audio Frequency Mute (AFM)
7.12.4 Specification of mute modes
7.13 MPX decoder
7.14 Signal depending mono/stereo blend (stereo noise cancellation)
7.15 Software programmable port
With the MU bit of the TNCTRL register byte 2 (see
VAFR can be hard-muted; this means they are put in high-impedance state. The same
can be done by setting the bits Left Hard Mute (LHM) or Right Hard Mute (RHM) in
register TESTREG (see
both set). When one output is muted the stereo decoder switches to mono. When he
TEA5766UK is in Standby mode the audio outputs are in high-impedance state (see
Table
With the AFM bit of the TNCTRL register byte 1, the audio signal can be muted. The audio
pins maintain their functional impedance and DC-biasing level while the audio signal is
muted. The audio frequency mute is automatically activated during preset as well as
search tuning modes as shown in the flowchart of
can be disabled in software test mode when bit TM = 1 and bit AFMDIS = 1.
Table 4.
The stereo decoder PLL is adjustment free. The stereo decoder can be switched to mono
via the control interface.
With decreasing RF input level the MPX decoder blends from stereo to mono to limit the
output noise. The continuous mono-to-stereo blend can also be programmed via the
control interface to an RF level depending switched mono to stereo transition. Stereo
noise cancellation can be switched on or off via the control interface using bit SNC in
register TNCTRL (see
switches from mono to stereo instead of blending. The RF input voltage where blending
starts can be switched with bit SNCLEV in register TESTREG (see
One software programmable port SWPORT (CMOS output) is available and can be
controlled via the control interface. With bit SWPM = 1 the software port (pin SWPORT)
functions as the output for the FRRFLAG and with bit SWPM = 0 the software port output
follows bit SWP. Bits SWP and SWPM are in register TNCTRL
Type
AFM
RHM
LHM
MU
Standby
SMUTE
4).
Description
audio frequency
mute
right hard mute 350
left hard mute
hard mute
standby
soft mute
Specification of mute modes
Table
Rev. 01 — 22 March 2007
Table
VAFL
Impedance
350
> 500 k
> 500 k
> 1 M
RF sensitive audio level; has no influence on mute pin or impedance
16). When stereo noise cancellation is switched off, the radio
19), which mute only one output at a time (or both when
Mode
muted
mono audio
muted
muted
-
Figure
Table
16), the audio outputs VAFL and
4. The audio frequency mute
VAFR
Impedance
350
> 500 k
350
> 500 k
> 1 M
(seeTable
TEA5766UK
Stereo FM radio + RDS
Table
© NXP B.V. 2007. All rights reserved.
16). In software
19).
Mode
muted
muted
mono audio
muted
-
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