Texas Instruments LM49370RLEVAL Evaluation Board LM49370RLEVAL/NOPB LM49370RLEVAL/NOPB 데이터 시트
제품 코드
LM49370RLEVAL/NOPB
SNAS356D – FEBRUARY 2007 – REVISED MARCH 2012
Table 31. STATUS (0x18h)
(continued)
Bits
Field
Description
3
BTN
This field is high when the button on the headset is pressed (only valid if the detection system is enabled).
IRQ is cleared when the button has been released and this register has been written to.
IRQ is cleared when the button has been released and this register has been written to.
(2)
4
TEMP
If this field is high then a temperature event has occurred (write to this register to clear IRQ). This field will
stay high even when the IRQ is cleared so long as the event occurs. This bit is only valid whenever the
loudspeaker amplifier is turned off.
stay high even when the IRQ is cleared so long as the event occurs. This bit is only valid whenever the
loudspeaker amplifier is turned off.
(2)
5
GPIN1
When GPIO_SEL is set to a readable configuration a digital input on GPIO1 can be read back here.
6
GPIN2
When GPIO_SEL is set to a readable configuration, a digital input on the relevant GPIO can be read back
here.
here.
3D CONFIGURATION REGISTER
This register is used to control the configuration of the 3D circuit.
Table 32. 3D (0x19h)
Bits
Field
Description
0
3D_ENB
Setting this bit enables the 3D effect. When cleared to zero, the 3D effect is disabled and the 3D module
then passes the I
then passes the I
2
S left and right channel inputs to the DAC unchanged. The stereo AUX inputs are
unaffected by the 3D module.
1
3D_TYPE
This bit selects between type 1 and type 2 3D sound effect. Clearing this bit to zero selects type 1 effect and
setting it to one selects type 2.
Type1: Rout = Ri-G*Lout3d, Lout = Li-G*Rout3d
Type2: Rout = -Ri-G*Lout3d, Lout = Li+G*Rout3d
where,
Ri = Right I
setting it to one selects type 2.
Type1: Rout = Ri-G*Lout3d, Lout = Li-G*Rout3d
Type2: Rout = -Ri-G*Lout3d, Lout = Li+G*Rout3d
where,
Ri = Right I
2
S channel input
Li = Left I
2
S channel input
G = 3D gain level (Mix ratio)
Rout3d = Ri filtered through a high-pass filter with a corner frequency controlled by FREQ
Lout3d = Li filtered through a high-pass filter with a corner frequency controlled by FREQ
Rout3d = Ri filtered through a high-pass filter with a corner frequency controlled by FREQ
Lout3d = Li filtered through a high-pass filter with a corner frequency controlled by FREQ
3:2
LEVEL
This programs the level of 3D effect that is applied.
LEVEL
00
2
25%
01
2
37.5%
10
2
50%
11
2
75%
5:4
FREQ
This programs the HPF rolloff (-3dB) frequency of the 3D effect.
FREQ
00
2
0Hz
01
2
300Hz
10
2
600Hz
11
2
900Hz
6
ATTENUATE
Clearing this bit to zero maintains the level of the left and right input channels at the output. Setting this bit
to one attenuates the output level by 50%.
This may be appropriate for high level audio inputs when type 2 3D effect is used. Type 2 effect involves
adding the same polarity of left and right inputs to give the final outputs. Type 2 effect has the potential for
creating a clipping condition, however this bit offers an alternative to clipping.
to one attenuates the output level by 50%.
This may be appropriate for high level audio inputs when type 2 3D effect is used. Type 2 effect involves
adding the same polarity of left and right inputs to give the final outputs. Type 2 effect has the potential for
creating a clipping condition, however this bit offers an alternative to clipping.
7
CUST_COMP
If set, the DAC compensation filter may be programmed by the user through registers (0x20h) to( 0x25h).
Otherwise, the defaults are used.
Otherwise, the defaults are used.
Copyright © 2007–2012, Texas Instruments Incorporated
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