TC9404FNG Datasheet, PDF (10/15 Pages) Toshiba Semiconductor – Σ-Δ Modulation System DA Converter with Analog Filter

TC9404FNG
(1) Digital attenuator
The digital attenuation command is enabled when D7 = “L”. The attenuation data can be set in 128
different ways. The relationship with the command’s output is shown below.
Table 6 Attenuation Data/Audio Data Output
Attenuation Data D6~D0
7F (HEX)
7E (HEX)
:
01 (HEX)
00 (HEX)
Audio Output
−0.000dB
−0.069dB
:
−42.076dB
−∞
01 (HEX) to 7E (HEX): The attenuation value is obtained with the following equation.
ATT = 20 ℓog (input data/127) dB
Example: In case of attenuator = 7 A
ATT = 20 ℓog (122/127) dB = −0.349dB
(2) Digital de-emphasis filter
The Digital De-emphasis setting mode is enabled when D7 = “H”.
Controlled with µEMP and µBS signal.
Table 7 Digital De-Emphasis Filter Setting
µBS
µEMP
Mode
H
H
L
L
H
L
H
L
32
48
44.1
OFF (kHz)
10
2006-04-27