TC9404FNG Datasheet, PDF (8/15 Pages) Toshiba Semiconductor – Σ-Δ Modulation System DA Converter with Analog Filter

TC9404FNG
7. Soft Mute Circuit
The IC is equipped with a soft mute function, and this enables a soft mute to be set for the DA converter
output by switching the SM pin (pin 18) from the “L” level to the “H” level when in the parallel mode ( P/S
= “H”). The soft mute’s ON/OFF function and the DA converter output are shown in Figure 9.
The Soft mute ON/OFF control function is disabled during level transition.
Figure 9 Changes in The Soft Mute DA Converter Output Level
8. Common left Channel/Right Channel Digital Zero Data Detection Output Circuit
The IC is equipped with a common left channel/right channel digital zero data detection output circuit,
and the ZD pin (pin 11) is switched from “L” to “H” when data for both the left channel and the right
channel becomes zero data for approximately 350 ms or longer.
This is fixed at “L” when the data for the left channel and right channel is not zero data.
9. Description of Internal Control Signals
The P/S pin can be used to switch between the parallel mode ( P/S pin = “H” in DC setting mode) and
the serial mode ( P/S pin = “L” with the microcontroller interface function).
9-1 Parallel Mode ( _P/S = “H”: DC setting mode)
Pins 18, 19 and 20 are used as the mode setting pins shown in the table below when in the parallel
mode.
Table 3 Pin Names at the Parallel Mode
Pin No.
18
19
20
Pin Name
Function
BS
EMP
SM
De-emphasis filter mode select pin
De-emphasis filter control pin
Soft mute control pin
8
2006-04-27