stv8226t STMicroelectronics, stv8226t Datasheet - Page 23

• Manufacturer Part Number: stv8226t
• Description: Multistandard Tv Audio Processor And Digital Sound Demodulator
• Manufacturer: STMicroelectronics

STV82x6
Note:
3.10
The Beeper operates in one of two modes:
In both modes, it is recommended to use the mute function to smooth the audio-to-beeper and
beeper-to-audio (Continuous mode only) transitions. The second transition is automatically muted
in Pulse mode. Beeper parameters are controlled in register BEEPER_CTRL.
The beeper tone level and frequency are programmed in register BEEPER_TONE. The level (or
volume) ranges between 0 dB and -93 dB in steps of 3 dB and the tone frequency ranges between
62.2 Hz and 8 kHz in steps of 1 octave.
A beep generator is shared only by the Loudspeaker or Headphone outputs. Therefore, in the event
of simultaneous beeps when in Pulse mode, only the first beep will define the effective duration that
will be the same for both outputs.
The audio output is not affected by the Automatic Mute Control of Automatic Standard Recognition
function when the beeper is activated.
SRS™ 3D Surround (STV8226/36 only)
In addition to ST WideSurround, the STV8226/36 provides SRS™ 3D Stereo and Mono outputs
which are spatial effects patented by SRS Labs. The SRS™ system is available on the IC when the
SRS_ON bit of register
systems cannot be used simultaneously. These signals are output only on the Loudspeaker path.
●
●
Pulse mode (beep applications) A tone with a programmable short duration (between 128 ms
and 1 s) is generated. Afterwards, the beeper is automatically disabled and the output is
switched back to the audio signal.
Continuous mode (alarm application) A tone with a programmable long duration is generated.
Its start and stop controls must be programmed by I²C.
62.5 Hz < F < 8 kHz
BEEP_ON = 1
62.5 Hz < F < 8 kHz
BEEP_ON = 1
CUT_ID
0.125s < T < 1s
T predefined
T defined by I²C write
Figure 14: Continuous Mode
is set (STV8226/36 identification). ST and SRS™ Surround
Figure 13: Pulse Mode
BEEP_ON = 0
BEEP_ON = 0
Audio Processor Block
23/97