AK4120 Datasheet, PDF (24/30 Pages) Asahi Kasei Microsystems – Sample Rate Converter with Mixer and Volume

ASAHI KASEI
[AK4120]
n System Reset
The AK4120 is reset by bringing the power down pin “PDN” =“L”. The digital filters are also reset when this occurs.
The AK4120 should be reset once by bringing PDN =“L” upon power-up. After a reset, the required clocks shown in
Table 2 must be input.
The SRC block starts 2*LRCK1 or 2*LRCK2 after a reset. The SRC block starts outputting data 2053*ORCK after a
reset occurs. Before 2053*ORCK, the SRC block outputs “L”.
n Zero cross detection function of Volume
When ZELM=“0”, the Zero Cross detection function is enabled. Then, if a Volume value is written to the register, the
volume will not change until a Zero crossing is detected or this process times out. The ZTM1-0 bits in 01H set this
timeout. When ZELM=“1”, Volume changes soon after volume value is written.
(3) Zero crossing timeout(ZTM1-0 )
(1)
(2)
Figure 20. Zero crossing process
(1) At this point, volume value is written in register.
(2) This is a zero crossing point. At this point, volume is changed.
(3) This is time of Zero crossing timeout that is set by ZTM1-0.
MS0134-E-00
- 24 -
2002/1