uda1331h NXP Semiconductors, uda1331h Datasheet - Page 12

• Manufacturer Part Number: uda1331h
• Description: Universal Serial Bus Usb Audio Playback Peripheral App
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Table 3 Volume control characteristics
M
Mute is one of the sound features as defined in the “USB
Device Class Definition for Audio Devices” . The mute
control request data bMute controls the position of the
mute switch. The position can be either on or off. When
bMute is true the feature unit is muted. When bMute is
1998 Oct 06
false the feature unit is not muted.
When the mute is active for the master channel, the value
of the sample is decreased smoothly to zero following a
raised cosine curve. There are 32 coefficients used to step
down the value of the data, each one being used 32 times
before stepping to the next.
UTE CONTROL
B15
Universal Serial Bus (USB) Audio
Playback Peripheral (APP)
...
...
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
B14
...
...
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
B13
...
...
0
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
B12
wVOLUME
...
...
0
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
B11
...
...
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
B10
...
...
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
B9
...
...
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
12
This amounts to a mute transition of 23 ms at
f
returned to the full level again following a raised cosine
curve with the same coefficients being used in reversed
order. The mute, on the master channel is synchronized to
the sample clock, so that operation always takes place on
complete samples.
A mute can be given via the host or by pressing a
predefined GP pin.
s
= 44.1 kHz. When the mute is released, the samples are
B8
...
...
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
0
VOLUME USB SIDE
(dB)
...
...
0
10
59
60
61
62
1
2
3
4
5
6
7
8
9
Preliminary specification
VOLUME USB APP
UDA1331H
(dB)
...
...
0
10
59
60
1
2
3
4
5
6
7
8
9