ak4538 AKM Semiconductor, Inc., ak4538 Datasheet - Page 18

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

ASAHI KASEI
n Master Clock Source
The AK4538 requires a master clock (MCLK). This master clock is input to the AK4538 by connecting a X’tal oscillator
to XTI and XTO pins or by inputting an external CMOS-level clock to the XTI pin or by inputting an external clock that is
greater than 50% of the DVDD level to the XTI pin through a capacitor.
When using a X’tal oscillator, there should be capacitors between XTI/XTO pins and DVSS. When using an external
clock, there are two choices: direct, where an external clock is input directly to the XTI pin and indirect, where the external
clock is input through a capacitor.
(1) X’tal Oscillator
MS0198-E-01
X’tal Oscillator
External Clock Direct Input (Figure 14)
AC Coupling Input
- Note: The capacitor values depend on the X’tal oscillator used. (C : typ. 10 30pF)
Master Clock
C
C
Table 1. Master Clock Status by PMXTL bit and MCKPD bit
XTO
XTI
(Figure 13)
(Figure 15)
OPERATION OVERVIEW
25k
MCKIPD= "0"
PMXTL = "1"
Figure 13. X’tal mode
Clock isn’t input to MCKI pin.
Clock is input to MCKI pin.
Clock is input to MCKI pin.
MCKI pin is fixed to “H”.
MCKI pin is fixed to “L”.
MCKI pin is Hi-Z
Oscillator OFF
- 18 -
Oscillator ON
Status
AK4538
PMXTL bit
1
0
0
0
0
0
1
0
MCKPD bit
0/1
0
1
0
0
1
0
1
[AK4538]
2003/5