SM5846AP Datasheet, PDF (36/36 Pages) Nippon Precision Circuits Inc – Multi-function Digital Filter

SM5846AP
Internal control flag/D-ATT attenuator
register initial values
Register
D-ATT attenuation
Mode flag 1
Mode flag 2
Mode flag 3
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
Bit 8
0
a1 = 0
a2 = 0
a3 = 0
a4 = 0
a5 = 0
a6 = 0
a7 = 0
1
0
SYNC = 1 TEST1 = 0 HS = 1 FSEL1 = 1 FSEL2 = 1 DEEM = 0
1
1
MUTE = 1 DITH = 1 OBS = 0 IBS1 = 1 IBS2 = 0
1
1
1
ASEL1 = 1 ASEL2 = 1
1
TEST2 = 1
1
0
When external muting is required
The SM5846AP has a relatively long group delay
time because multi-stage filters are employed to
achieve the desired filter characteristics. Under the
following conditions, undesirable noise output can
occur during the group delay time period. In this
case, it may be necessary to use external muting.
s When power is first applied.
The state of internal registers may be undefined
during power-ON.
s When switching the operating mode.
When switching the operating mode using HS,
ASEL1 and ASEL2, the internal register assign-
ments may be changed.
s If the LRCI and/or XTI clock stop.
If a disturbance occurs during an input data cycle,
normal filter output may not be achieved.
s When switching deemphasis ON/OFF.
Switching the deemphasis filter parameters may
cause switching noise output.
s When switching the sampling frequency (clock
frequency).
s When switching between input/output data for-
mats (including LRCI clock polarity switching).
Note that switching MDS is inhibited during system
operation.
Test Precautions
The following conditions should be maintained for
normal operation.
s MDS and DITH inputs should not be simulta-
neously LOW.
s TEST1 (bit 4 of mode flag 1 register) should not
be set to 1.
s TEST2 (bit 4 of mode flag 3 register) should be set
to 0 after system reset (including power-ON).
s Mode flag 3 register bit 5 and/or bit 7 should not
be set to 0.
Audio
ICs
NIPPON PRECISION CIRCUITS INC. reserves the right to make changes to the products described in this data sheet in order to
improve the design or performance and to supply the best possible products. Nippon Precision Circuits Inc. assumes no responsibility for
the use of any circuits shown in this data sheet, conveys no license under any patent or other rights, and makes no claim that the circuits
are free from patent infringement. Applications for any devices shown in this data sheet are for illustration only and Nippon Precision
Circuits Inc. makes no claim or warranty that such applications will be suitable for the use specified without further testing or modification.
The products described in this data sheet are not intended to use for the apparatus which influence human lives due to the failure or
malfunction of the products. Customers are requested to comply with applicable laws and regulations in effect now and hereinafter,
including compliance with export controls on the distribution or dissemination of the products. Customers shall not export, directly or
indirectly, any products without first obtaining required licenses and approvals from appropriate government agencies.
NIPPON PRECISION CIRCUITS INC.
NIPPON PRECISION CIRCUITS INC.
4-3, Fukuzumi 2 chome
Koto-ku, Tokyo 135-8430, Japan
Telephone: [phone]
Facsimile: 03-3642-6698
NC9616BE 1998.01
NIPPON PRECISION CIRCUITS—36