NJU26170 Japan Radio Co., NJU26170 Datasheet - Page 6

• Manufacturer Part Number: NJU26170
• Description: Nju26100 Series Hardware Specification
• Manufacturer: Japan Radio Co.

3. Audio Clock
That is, for each audio sample originated by an audio source there must be one and only one audio sample
processed by the NJU26100 Series and delivered to the D/A converters. To accomplish this, one device in the
system is selected to generate the audio sample rate; the remaining devices are designated to follow this sample
rate. The device that generates the audio sample rate is called the MASTER device; all devices following this
sample rate are called SLAVE(s).
MASTER mode, the NJU26100 Series system clock should be 768 multiples of the sampling frequency (Table3-1).
When the NJU26100 Series is in SLAVE mode, NJU26100 Series system clock should be from 768 multiples of
the sampling frequency up to the maximum operating frequency.
3.1 System Clock
and BCK (BCKI and BCKO) establish data transfer on the serial data lines. The third clock, MCK, is not associated
with serial data transfer but is required by delta-sigma A/D and D/A converters.
at multiples of the LR clock rate. Therefore the signals LR, BCK and MCK must be locked, that is, they must be
generated or derived from a single frequency reference. In SLAVE mode, the NJU26100 Series dose not generate
MCK clock.
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Three types of clock signals are included in the serial audio interface. Two of the clock signals LR (LRI and LRO)
The frequency of the LR clock is, by definition, equal to the digital audio sample rate, Fs. BCK and MCK operate
Audio data samples must be transferred in synchronism between all components of the digital audio system.
LR, BCK and MCK should be synchronized. This is described in next section. When the NJU26100 Series is in
MCK(256Fs)
MCK(384Fs)
Clock Signal
BCK(32Fs)
BCK(64Fs)
Table 3-1 Sampling Frequency and BCK, MCK, XI
LR
XI
Multiple Frequency
256Fs
384Fs
768Fs
32Fs
64Fs
1Fs
Fig. 3-1 MASTER / SLAVE Mode
SDIx
BCKI
LRI
12.288MHz
24.576MHz
1.024MHz
2.048MHz
8.192MHz
32kHz
32kHz
XI
Oscillator
DIVIDER
CLOCK
XO
BCKO
SDOx
MCK
LRO
MAS TER
33.8688MHz
SLAVE
1.4112MHz
11.289MHz
16.934MHz
2.822MHz
44.1kHz
44.1kHz
12.288MHz
18.432MHz
36.864MHz
1.536MHz
3.072MHz
48kHz
48kHz
Ver.2005-02-24