FEDL22620-01
ML22620
SPP pin and SPM pin short detection
Set the SPP pin and SPM pin short detection with the SPDEN bit of the SAFE command.
Detects short circuit between SPP pin and SPM pin, or SPP pin and GND (ground fault), or SPM pin and GND (ground
fault). Can be used when SPV
DD
≥
4.5V. Operation is started by analog power-up in the speaker amplifier output mode by
the AMODE command, and operation is terminated by power-down in the speaker amplifier output mode by the AMODE
command.
After inputting SAFE command, start the analog power-up operation by AMODE command within 10ms.
When a short-circuit is detected, the error bit (SPDERR) is set to "1". When using a class D amplifier with the DAMP bit of
AMODE command set to "1", if the PWM output is fixed to "H" level for 62.5us or longer, the error bit (SPDERR) is set to
"1". At the same time, the speaker amplifier output pin (SPP/SPM) is forcibly turned off. Read the error bit (SPDERR) with
the RDERR command, end playback, and perform analog power-down with the AMODE command. Then, use ERRCL
command to clear the error bit (SPDERR).
To restart playback, use the AMODE command to analog power-up the speaker amplifier output mode and enter the PLAY
command. However, if shorting to ground continues, the error bit (SPDERR) is set to "1" and the speaker amplifier output pin
(SPP/SPM) is forcibly turned off simultaneously.
Short detection prevents damage to LSI. However, the detection circuit is effective in preventing damage due to
unexpected accidents. It does not support continuous short operation or transient use.
*1 Set 1 SPDEN = "1"
*2 Analog power-up in speaker amplifier output mode
*3 Analog power-down in speaker amplifier output mode
*4 Misoperation detection and failure detection outputs are selected by OUTSTAT command.
Command
STATUSn
*4
(n
:
1 or 2)
SPP
SPM
Status
SPV
DD
SPGND
SPV
DD
SPGND
analog power-down
speaker power-down
analog power-up
speaker power-up
HiZ
SPP pin and SPM pin short detection
is operating
SPDERR
Short detection
PUP
SAFE
*1
AMODE
*2
ERRCL
AMODE
*3
AMODE
*2
RDERR
analog power-down
speaker power-down
analog power-up
,
speaker power-up
SPP pin and SPM pin short detection
is operating
HiZ
SPDEN
10ms
27/115
Summary of Contents for LAPIS Semiconductor ML22620
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