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TLV320AIC3109-Q1
www.ti.com.cn
ZHCSGM5A –AUGUST 2017–REVISED NOVEMBER 2017
版权 © 2017, Texas Instruments Incorporated
7.3 Feature Description
7.3.1 Hardware Reset
The TLV320AIC3109-Q1 requires a hardware reset after power-up for proper operation. After all power supplies
are at their specified values, the RESET pin must be driven low for at least 10 ns. If this reset sequence is not
performed, the TLV320AIC3109-Q1 may not respond properly to register reads or writes.
This device also offers a software reset (page 0, register 1) that can be used by the host to reset all registers on
page 0 and page 1 to their reset values. In cases where changes are needed only for routing or volume-control
registers, these changes can be accomplished by writing directly to the appropriate registers rather than using
the software or hardware reset.
In cases where the ESD events generate a device reset, a minimum 1-nF capacitor is recommended to be
connected between the RESET pin and DVSS. This capacitor avoids ESD events that can place the codec in
default state.
7.3.2 Digital Audio Data Serial Interface
Audio data are transferred between the host processor and the TLV320AIC3109-Q1 via the digital audio data
serial interface. The audio bus of the TLV320AIC3109-Q1 can be configured for left- or right-justified, I
2
S, DSP,
or TDM modes of operation, where communication with standard PCM interfaces is supported within TDM mode.
These modes are all MSB-first, with data width programmable as 16, 20, 24, or 32 bits. In addition, the word
clock (WCLK) and bit clock (BCLK) can be independently configured in either master or slave mode for flexible
connectivity to a wide variety of processors.
The word clock (WCLK) is used to define the beginning of a frame, and can be programmed as either a pulse or
a square-wave signal. The frequency of this clock corresponds to the selected ADC and DAC sampling
frequency.
The bit clock (BCLK) is used to clock in and out the digital audio data across the serial bus. When in master
mode, this signal can be programmed in two further modes: continuous transfer mode, and 256-clock mode. In
continuous transfer mode, only the minimal number of bit clocks required to transfer the audio data are
generated, so in general the number of bit clocks per frame is two times the data width. For example, if the data
width is chosen as 16 bits, then 32-bit clocks are generated per frame. If the bit clock signal in master mode is to
be used by a PLL in another device, then the 16-bit or 32-bit data-width selections are recommended be used.
These cases result in a low-jitter bit clock signal being generated, with frequencies of 32 f
S
or 64 f
S
. For a 20-bit
and 24-bit data width in master mode, the bit clocks generated in each frame are not all of equal period because
the device does not have a clean 40-f
S
or 48-f
S
clock signal readily available. The average frequency of the bit
clock signal is still accurate in these cases (40 f
S
or 48 f
S
), but the resulting clock signal has higher jitter than in
the 16-bit and 32-bit cases.
In 256-clock mode, a constant 256 bit clocks per frame are generated, independent of the data width chosen.
The TLV320AIC3109-Q1 further includes programmability to place the DOUT line in the high-impedance state
during all bit clocks when valid data are not being sent. By combining this capability with the ability to program at
what bit clock in a frame the audio data begins, time-division multiplexing (TDM) can be accomplished, resulting
in multiple codecs able to use a single audio serial data bus.
When the digital audio data serial interface is powered down when configured in master mode, the pins
associated with the interface are put into a high-impedance state.
The following subsections describe the supported data interface protocols. These protocols can be used for left-
and right-channel applications. Only one of the two possible channels can be selected because the
TLV320AIC3109-Q1 is a mono audio codec. Only the left channel is valid for DOUT (output data). For DIN (input
data), valid data can be selected with bits 4 and 3 of register 7, page 0.