AK7750 Datasheet, PDF (71/77 Pages) Asahi Kasei Microsystems – Audio DSP with Built-in Hands-Free Phone Features

[ASAHI KASEI]
[AK7750]
(11) Hands-free mode
The AK7750 has hands-free mode in addition to normal surround mode.
The write “1” to HF_RST_N bit and HF bit in CONT5 register under system reset ( S _RESET =”L”) allows the
AK7750 to hands-free operation mode. The AK7750 returns to surround mode by the execution of
initial reset or the clear of HF_RESETN bit and HF bit.
The AK7750 can change the attenuation level of noise canceller. If PID bit of CONT5 register is “0”, the
default attenuation level is used. If PID bit is “1”, the attenuation level which is stored in the hands-free
parameter RAM is used.
Hands-free parameter must be downloaded to the address AFTER the AK7750 switches to hands-free
mode.
Please contact AKM for the detail of hands-free parameter contents.
S _ RESET
RQ
SCLK
SI
6Ah ECh
control register CONT5
Hands-free mode ON
E0h 00h DATA0
DATA6
writing hands-free
parameter RAM
other DATA
[MS0296-E-00]
71
2005/03