MeiG
Product
Manual
of
SLM750
Module
SLM750
Module
Hardware
Design
Page 46, total 84 pages
Parameter
Min
Max
Unit
V
IL
-0.3
0.6
V
V
IH
1.2
2.0
V
V
OL
0
0.45
V
V
OH
1.35
1.8
V
SLM750 provides 1.8V serial port. If your application serial port is 3.3V, you need to add level
converter. It is recommended that you use TXB0104PWR from TI Company. Reference design is
shown as follows:
Figure 17 Reference circuit of level conversion chip
3.12 PCM and I2C Interface
SLM750 provides one PCM interface which supports the following two modes:
Short frame mode: the module works as both master and slave
Long frame mode: the module works as master only
In short frame mode, the data is sampled on the falling edge of the PCM_CLK and transmitted
on the rising edge; the PCM_SYNC falling edge represents the more significant bit. PCM_CLK
supports 128, 256, 512, 1024 and 2048kHz speech codes.
In long frame mode, the data is sampled on the falling edge of the PCM_CLK and transmitted
