Hi,
I received questions about TAS5424C from a customer.
Q1. He initialized TAS5424C in the following procedure, but the PlayMode bits in ExternalStatusReg3(0x06) would not turn on and sound was not output.
(1)14V is supplied to PVDD.
(2)/STANDBY is disabled (voltage is High level).
(3)/FAULT terminal changes to Low.
(4)FaultReg(0x00) is 0x30.
(5)/FAULT terminal changes to High.
(6)FaultReg(0x00) is 0x00.
(7)/MUTE is disabled (voltage is High level).
(8)write 0x00 or 0x10 to ExternalContorlReg5(0x0C).
(9)ExternalStatusReg3(0x06) is 0x00, it does not chage to 0x0F. ExternalStatusReg2(0x05) is 0x00 too.
He thinks that the above procedure is based on '2.2 Power Up and Initialization' and '2.3 Using the Device to Play Music' of TAS54x4C Design Guide.
However, the register 0x05, 0x06 and 0x07 did not change from 0x00. Why did these registers not change?
Q2.About the /MUTE pin connection.
A)If the mute processing is controlled only by the register via I2C, is it permitted that the circuitry connected to MUTE terminal is only a 220nF capacitor without transistor?
B)If the mute processing is controlled not only by the register but also MUTE pin by H/W, is tolerance of maximum MUTE terminal voltage 8.5V required to a connected open-drain transistor?
C) Is it all right just to connect GPIO (Vo_max=5.5V) of the microcontroller?
Best regards,
Akio Ito
