AKM AK4534, Руководство пользователя

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ASAHI KASEI [AK4537]
MS0202-E-04 2005/04
- 67 -
„
Headphone-amp Output
FS2-0 bits
(Addr:05H, D7-5)
ATTL7-0 bits
(Addr:0CH 0DH, D7-0)
HPL/R bit
(Addr:03H, D1-0)
PMHPL/R bits
(Addr:01H, D2-1)
HPL/R pins
XXX 000
0000000 XXXXXXX
Normal Output
External Mute
(1)
BST1-0 bits
(Addr:06H, D3-2)
00 XX 00
(2)
(3)
(7) (8)
(12)
PMDAC bit
(Addr:01H, D0)
(4) (11)
(5)
(9) (6)
(10)
E x a m p le :
X ’ta l a n d P L L a re u s e d .
S a m p lin g F r e q u e n c y : 4 4 . 1 k H z
D A T T C b it = “1 ” (d e f a u lt)
D ig it a l A tte n u a to r L e v e l : -8 d B
B a s s B o o s t L e v e l : M id d le
D e - e m p h a s e s re s p o n s e : O F F
S o f t M u te T im e : 1 0 2 4 /f s
( 1 ) A d d r: 0 5 H , D a t a : 0 0 H
( 3 ) A d d r: 0 C H , D a t a 1 0 H
( 4 ) A d d r: 0 1 H , D a t a 6 1 H
( 7 ) R e le a s e e x t e r n a l M u t e
P la y b a c k
( 2 ) A d d r: 0 6 H , D a t a 1 9 H
( 8 ) E n a b le e x t e rn a l M u t e
( 9 ) A d d r: 0 1 H , D a t a 6 1 H
( 1 0 ) A d d r : 0 2 H , D a t a 8 3 H
( 5 ) A d d r: 0 2 H , D a t a 8 0 H
( 6 ) A d d r: 0 1 H , D a t a 6 7 H
( 1 1 ) A d d r : 0 1 H , D a t a 6 0 H
( 1 2 ) A d d r : 0 6 H , D a t a 1 1 H
Figure 55. Headphone-Amp Output Sequence
<Example>
At first, clocks should be supplied according to “Clock Set Up” sequence.
(1) Set up a sampling frequency (FS2-0 bits) if PLL mode is used.
(2) Set up the low frequency boost level(BST1-0 bits)
(3) Set up the digital volume(Addr : 0CH and 0DH)
At DATTC bit = “1”(default), ATTL7-0 bits of Address 0CH control both Lch and Rch attenuation level.
(4) Power up DAC : PMDAC bit = “0”
o
“1”
(5) Power up headphone-amp : HPL bit = HPR bit = “1”
o
“0”
Output voltage of headphone-amp is still HVSS.
(6) Rise up the common voltage of headphone-amp : PMHPL bit = PMHPR bit = “0”
o
“1”
The rising time after power up Headphone-amp depends on the capacitor value connected with the MUTET
pin. When this capacitor value is 1.0
P
F, the time constant is
W
r
= 100ms(typ), 250ms(max).
(7) Release the external mute.
(8) Enable the external mute.
(9) Fall down the common voltage of headphone-amp : PMHPL bit = PMHPR bit = “1”
o
“0”
The rising time after power up Headphone-amp depends on the capacitor value connected with the MUTET
pin. When this capacitor value is 1.0
P
F, the time constant is
W
f
= 100ms(typ), 250ms(max).
If the power supply is powered off or Headphone-Amp is powered-down before the common voltage goes to
GND, some POP noise occurs. It takes 2times of
W
f
that the common voltage goes to GND.
(10) Power down headphone-amp : HPL bit = HPR bit = “0”
o
“1”
(11) Power down DAC : PMDAC bit = “1”
o
“0”
(12) Off the low frequency boost level (BST1-0 bits = “00”)
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