Sound Noise Issue Noise at the initial part

1. Shutdown pin is always low(Active AMP) : continued…. Codec PWR On/Off P 1

2. Shutdown pin is controlled ☞ A sound is played The noise is cleared

2. Shutdown pin is controlled : continued… ☞ A sound is played repeatedly :

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<<Sound Noise Issue>> - Noise at the initial part and the end part of a sound play 1. Shutdown pin(AMP) is always low(Active AMP) ☞ A sound is played Noise at the initial part P 3 P 1 Codec power on P 4 P 2 P 1 P 3 P 4 AMP SPK Codec Out : SPK_OUT P 5 SHUTDOWN

1. Shutdown pin is always low(Active AMP) : continued…. Codec PWR On/Off P 1 P 4 DC very low noise P 5 AC P 4 – P 5 Noise at the end part P 4 SPK P 5 SHUTDOWN Could you recommend any solution to clear these noises ? ? ?

2. Shutdown pin is controlled ☞ A sound is played The noise is cleared by the Shutdown control Codec power on P 1 P 4 SHUTDOWN [[ Operation Sequence ]] 1. Codec Power On 2. Ext. AMP On(SHUTDOWN Low) 3. 100 ms Delay 4. Sound output 5. Ext. AMP Off(SHUTDOWN High) 6. Codec Power Off SHUTDOWN P 4 P 5 P 4 - P 5

2. Shutdown pin is controlled : continued… ☞ A sound is played repeatedly : codec power is still on After 2’nd play Codec power on P 4 SHUTDOWN After the 2’nd play, there is a noise at the initial part of the sound [[ Operation Sequence ]] 1. Codec Power On(Register 0 x 3 C/0 x 3 E) 2. Ext. AMP On(SHUTDOWN Low) 3. 100 ms Delay 4. Sound output 5. Operation 3/4 repeated…… 6. 7. Ext. AMP Off(SHUTDOWN High) Codec Power Off

2. Shutdown pin is controlled : continued… ☞ A sound is played repeatedly : codec power is still on After 2’nd play Codec power on (0 x 3 C/0 x 3 E) After 2’nd play P 4 P 5 P 4 - P 5 SHUTDOWN Could you recommend any solution to clear these noises ? ? ?

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