AK4953A Datasheet, PDF (51/96 Pages) Asahi Kasei Microsystems – 24bit Stereo CODEC with MIC/HP/SPK-AMP

[AK4953A]
■ BEEP Signal Generating Circuit
The AK4953A integrates a BEPP signal generating circuit. When PMSPK bit = “1”, the speaker amplifier outputs BEEP
signal by setting PMBP bit = “1”, and the Headphone amplifier outputs BEEP signal by setting PMBP bit = “1” when
PMHPL bit or PMHPR bit = “1”.
When PMDAC bit = “1” and PMHPL bit or PMHPR bit = “1”, switching noise of connection between the BEEP
generating circuit and headphone amplifier can be suppressed by soft transition. The transition time of ON/OFF switching
is set by PTS1-0 bits. Soft transition Enable/Disable is controlled by MOFF bit. When this bit is “1”, soft transition is
disabled and the headphone is switched ON/OFF immediately.
PTS1
bit
0
0
1
1
PTS0
bit
0
1
0
1
ON/OFF Time
7.35kHz ≤ fs ≤ 24kHz
24kHz < fs ≤ 48kHz
48kHz < fs ≤ 96kHz
64/fs 5.3 ~ 8.7ms 128/fs 2.7 ~ 5.3ms 256/fs 2.7 ~ 5.3ms
128/fs 10.7 ~ 17.4ms 256/fs 5.3 ~ 10.7ms 512/fs 5.3 ~ 10.7ms
256/fs 21.3 ~ 34.8ms 512/fs 10.7 ~ 21.3ms 1024/fs 10.7 ~ 21.3ms
512/fs 42.7 ~ 69.7ms 1024/fs 21.3 ~ 42.7ms 2048/fs 21.3 ~ 42.7ms
Table 43. BEEP (Headphone-Amp) ON/OFF Transition Time
(default)
After outputting the signal during the time set by BPON7-0 bits, the AK4953A stops the output signal during the time set
by BPOFF7-0 bits (Figure 37). The repeat count is set by BPTM6-0 bit, and the output level is set by BPLVL4-0 bits.
When BPCNT bit is “0”, if BPOUT bit is written “1”, the AK4953A outputs the beep for the times of repeat count. When
the output is finished, BPOUT bit is set to “0” automatically. When BPCNT bit is set to “1”, it outputs beep signals
incessantly regardless of repeat count, on-time nor off-time. The output frequency is set by BPFR1-0 bits.
< Setting parameter >
1) Output Frequency (Table 44, Table 45)
2) ON Time (Table 46, Table 47)
3) OFF Time (Table 48, Table 49)
4) Repeat Count (Table 50)
5) Output Level (Table 51)
* BPFR1-0, BPON7-0, BPOFF7-0, BPTM6-0 and BPLVL4-0 bits should be set when BPOUT
=BPCNT = “0”.
* BPCNT bit is given priority in BPOUT bit. When BPOUT bit is set to “1”, if BPCNT bit is set to
“0”, BPOUT bit is set to “0” forcibly.
* When stopping the BEEP outputs by changing BPCNT bit to “0” from “1”, writing to BPOUT and
BPCNT bits are inhibited for 10ms. When BEEP is output by setting BPCNT bit = “1”, writing to
BPOUT and BPCNT bits are inhibited for 10ms after BPOUT bit is changed to “0” or BEEP
signal outputs are finished (ON/OFF time and the number of times set by repeated time).
BEEP Output
ON Time
OFF Time
Repeat Count
Figure 37. BEEP Signal Output
MS1252-E-00
- 51 -
2010/10