MSP 3400C
PRELIMINARY DATA SHEET
2
13. I S Bus in Master/Slave Configuration with
Standby Mode
In a master/slave application, both MSP, after power up
andreset, willstartasmasterbydefault. Thismeansthat
before the slave MSP is set to slave-mode, relatively
large current-pulses (~20 mA) in the I2S_CL and
I2S_WS lines can cause some crackling noise during
startup time, if the the MSP is demuted before the slave
MSP is set to slave mode.
These high current pulses are also possible, if the active
I2S_CL and I2S_WS outputs of the master MSP are
clipped by the correspondent inputs of the slave MSP,
which is switched to standby mode.
To avoid this, it is recommended, that the I2S-bus lines
I2S_CL and I2S_WS are current-limited to about 5 mA
with series resistors of about 390 Ω (330...470 Ω).
Fig. 13–1 depicts the recommended application circuit
for two MSP 3410/00 or MSP 3400C, which are con-
nected via I2S Bus in a master/slave configuration, and
where the slave MSP can be switched in standby mode
(+5 Volt power is switched off).
Standby control
+5 V
18.432 MHz
18.432 MHz
62 63
18
DVSUP
7
62 63
STANDBYQ
I2S_DA_IN 14
13 I2S_DA_OUT
14 I2S_DA_IN
12 I2S_WS
MSP 3410/00
MSP 3400C
(master)
MSP 3410/00
MSP 3400C
(slave)
I2S_DA_OUT 13
I2S_WS 12
R
C
I2S_CL 11
11 I2S_CL
minimal corner frequency = 4 MHz
with R = 390 Ω (330–470 Ω)
2
Fig. 13–1: I S master/slave application
68
MICRONAS INTERMETALL
MICRONAS [ MICRONAS ]
