ak4121 AKM Semiconductor, Inc., ak4121 Datasheet - Page 14

• Manufacturer Part Number: ak4121
• Description: Asynchronous Sample Rate Converter
• Manufacturer: AKM Semiconductor, Inc.

ASAHI KASEI
T Grounding and Power Supply Decoupling
The AK4121 requires careful attention to power supply and grounding arrangements. VDD are usually supplied from
the system’s analog supply. AVSS and DVSS of the AK4121 must be connected to the analog ground plane.
System analog ground and digital ground should be connected together near to where the supplies are brought onto the
printed circuit board. Decoupling capacitors especially a 0.1 F ceramic capacitor for high frequency noise should be
placed as near to VDD as possible.
T PLL Loop-Filter
The C1 (4.7 F) and R (560ohms) should be connected in series and attached between FILT pin and AVSS in parallel
with C2 (1.0nF). Care should be taken to ensure that noise on the FILT pin is minimized.
MS0191-E-03
Parameter
fsi range
C1
C2
R
Note: Those recommended values include temperature dependence.
Recommended value 1
AK4121
Figure 7. PLL Loop-Filter
560ohm +/ 8%
4.7 F +/ 40%
1.0nF +/ 40%
8k ~ 96kHz
FILT
- 14 -
R
C1
AVSS
C2
Recommended value 2
1.2kohm +/ 8%
2.2 F +/ 40%
2.2nF +/ 40%
16k ~ 96kHz
[AK4121]
2004/08