SM5844 NPC [Nippon Precision Circuits Inc], SM5844 Datasheet - Page 16

• Manufacturer Part Number: SM5844
• Description: Asynchronous Sample Rate Converter
• Manufacturer: NPC [Nippon Precision Circuits Inc]

SM5844AF
Attenuator operation
A change in the attenuation data DATT causes the
gain to change smoothly from its previous value
towards the new setting. The new attenuation data is
stored in the attenuation data register and the current
attenuation level is stored in a temporary register.
Consequently, if a new attenuation level is read in
before the previously set level is reached, the gain
changes smoothly from the current value towards the
latest setting as shown in figure 4.
The attenuation counter output changes, and hence
the gain changes, by 1 step every output sample. The
time taken to reduce the gain from 0 dB (or 12 dB) to
dB is (1024/fso), which corresponds to
approximately 23.2 ms when fso = 44.1 kHz.
Level 1
Level 5
0 dB
Level 3
Gain
Level 2
t
Level 4
Time
Figure 4. Attenuator operation example
NIPPON PRECISION CIRCUITS—16