TA2170FTG Datasheet, PDF (5/12 Pages) Toshiba Semiconductor – Low Current Consumption Headphone Amplifier (Built-in input selector)

TA2170FTG
Application Notes
1. Mute switch and voltage gain
This IC is designed so that a volume feeling may not change with a single output and many outputs.
When the input signal to buffer amplifier is same and a linear domain, the relation between mute switches
and voltage gain are as follows.
Test condition: VCC = 3 V, f = 1 kHz, Vin = −20dBV, theoretical value
(1) 1 input mode
MUTE SW
MUTE1
MUTE1A
MUTE2
Input signal is applied to BUF 1.
OFF
OFF
ON
OFF
OFF
OFF
OFF
OFF
ON
OFF
OFF
OFF
OFF
ON
ON
OFF
ON
OFF
OFF
ON
ON
OFF
ON
OFF
Input signal is applied to BUF 2
ON
ON/OFF
OFF
ON
ON/OFF
OFF
OFF
OFF
OFF
OFF
ON
OFF
OFF
OFF
OFF
OFF
ON
OFF
Input signal is applied to BUF 3.
ON
ON/OFF
ON
ON
ON/OFF
OFF
OFF
OFF
ON
OFF
ON
ON
OFF
OFF
OFF
OFF
ON
OFF
MUTE3
Attenuation to an input signal (dB)
BUF1
BUF2
BUF3
Ach Bch Ach Bch Ach Bch
Total gain
(dB)
Ach Bch
ON
ON
OFF
OFF
ON
ON
OFF
OFF
0
0
⎯
⎯
−6
−6
⎯
⎯
−6
−6
⎯
⎯
−9.5 −9.5 ⎯
⎯
⎯
0
⎯
⎯
⎯
−6
⎯
⎯
⎯
−6
⎯
⎯
⎯
−9.5
⎯
⎯
⎯
⎯
0
0
⎯
⎯
−6
−6
⎯
⎯
−6
−6
⎯
⎯ −9.5 −9.5
⎯
⎯
⎯
0
⎯
⎯
⎯
−6
⎯
⎯
⎯
−6
⎯
⎯
⎯ −9.5
ON
OFF
ON
ON
OFF
OFF
⎯
⎯
0
0
⎯
⎯
0
0
⎯
⎯
−6
−6
⎯
⎯
−6
−6
⎯
⎯
−6
−6
⎯
⎯
−6
−6
⎯
⎯
0
−6
⎯
⎯
0
−6
⎯
⎯
−9.5 −9.5
⎯
⎯ −9.5 −9.5
⎯
⎯
−6
−9.5
⎯
⎯
−6 −9.5
OFF
OFF
OFF
OFF
OFF
OFF
⎯
⎯
⎯
⎯
0
0
0
0
⎯
⎯
⎯
⎯
−6
−6
−6
−6
⎯
⎯
⎯
⎯
−6
−6
−6
−6
⎯
⎯
⎯
⎯
0
−6
0
−6
⎯
⎯
⎯
⎯
−9.5 −9.5 −9.5 −9.5
⎯
⎯
⎯
⎯
−6 −9.5 −6 −9.5
5
2006-04-19