FEDL2215-01

1Semiconductor

ML2215

13/26

You must input the external clock to the CLK pin. Otherwise, serial data input cannot be acquired internally,

regardless t

Figure 4.2 Timing Chart of Serial Input

As shown in Figure 4.2, re-inputting the Start-bit before the SI’s 8th clock cancels the preceding serial data entry,

and 8-clock data following the Start-bit is taken as valid data.

4.2 3-pin Controlled Serial Input Interface

3-pin interfacing uses the SD, SI and

ST pins to control interfacing.

Figure 4.3 Timing Chart of Serial Input

When 3-pin interfacing is selected, input to the SD and SI pins is enabled while the

ST pin being held “L”. Serial

data input to the SD pin is acquired to the internal register in synchronization with the falling edge of the SI’s 8th

clock as an 8-bit phrase code for a user-defined phrase. If the

ST pin is brought back to “H” before the SI’s 8th

clock, the preceding entry is cancelled, and 8-clock data after the

ST pin being brought back to “L” again is taken

as valid data.

SD

SI

NAR

BUSY

t

SDST

t

SDST

SD

SI

NAR

BUSY

ST