ak4538 AKM Semiconductor, Inc., ak4538 Datasheet - Page 65

• Manufacturer Part Number: ak4538
• Description: 16bit ?? Codec With Mic/hp/spk-amp
• Manufacturer: AKM Semiconductor, Inc.

ASAHI KASEI
n
MS0198-E-01
Headphone-amp Output
<Example>
(Addr:0CH 0DH, D7-0)
At first, clocks should be supplied according to “Clock Set Up” sequence.
External Mute
ATTL7-0 bits
PMHPL/R bits
(Addr:05H, D7-5)
(Addr:01H, D2-1)
(Addr:06H, D3-2)
BST1-0 bits
(Addr:01H, D0)
HPL/R pins
(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)
(4) Power up DAC and headphone-amp : PMDAC bit = PMHPL bit = PMHPR bit = “0”
(5) Release the external mute.
(6) Enable the external mute.
(7) Power down DAC and headphone-amp : PMDAC bit = PMHPL bit = PMHPR bit = “1”
(8) Off the low frequency boost level (BST1-0 bits = “00”)
PMDAC bit
FS2-0 bits
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 F, the time constant is
The falling time of Headphone-amp depends on the capacitor for the AC couple of Headphone-amp output.
When this capacitor value is 47 F, the time constant is
Headphone-Amp is powered-up again before the common voltage goes to GND, some POP noise occurs. It
takes 5times of
At DATTC bit = “1”(default), ATTL7-0 bits of Address 0CH control both Lch and Rch attenuation level.
000
0000000
00
(1)
f
that the common voltage goes to GND.
(2)
(3)
Figure 54. Headphone-Amp Output Sequence
(4)
(5)
Normal Output
XX
XXX
XXXXXXX
- 65 -
(6)
(7)
(8)
f
= 188ms. If the power supply is powered off or
00
r
= 100ms.
E x a m p le :
X ’t a l a n d P L L a r e u s e d .
S a m p l i n 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 i g i t a l A t t e n u a t o r L e v e l : - 8 d B
B a s s B o o s t L e v e l : M i d d l e
D e - e m p h a s e s r e s p o n s e : O F F
S o f t M u t e T i m e : 1 0 2 4 / f s
( 1 ) A d d r : 0 5 H , D a t a : 0 0 H
( 2 ) A d d r : 0 6 H , D a t a 1 9 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 7 H
( 5 ) R e le a s e e x t e r n a l M u t e
( 6 ) E n a b le e x t e r n a l M u t e
( 7 ) A d d r : 0 1 H , D a t a 6 0 H
( 8 ) A d d r : 0 6 H , D a t a 1 1 H
P la y b a c k
“1”
“0”
[AK4538]
2003/5