ams AG AS3932 Nota applicativa - Pagina 6

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Application Note AS3932 - Migration from ATA5283 (1-channel) to AS3932

2.3

Serial Digital Interface

The AS3932 has a 4-wire serial data interface (CS, SDI, SDO, SCL) while the ATA5283 has no interface,

since no programmability is allowed. The Serial Digital Interface of AS3932 needs to be programmed accordingly

(see p. 16 to p. 18 of AS3932 data sheet).

2.4

Both AS3932 and ATA5283 have two dedicated pins for the wakeup and data; the only difference is that the

wakeup pin of ATA5283 (WAKEUP) has an inverted meaning compared to AS3932 (WAKEUP=high=no wakeup,

WAKEUP=low=wakeup)

2.5

Furthermore the AS3932 has a fully integrated Manchester clock recovery, which provides the recovered clock

on the pin CL_DAT. This pin is missing in the ATA5283, thus no clock recovery is possible. In case clock recovery

is not required, the pin CL_DAT of AS3932 can remain floating.

The ATA5283 wakes up if a carrier burst of at least 704 periods is followed by a "start gap" (no Signal); an

example is given in the figure 3-1.

Figure 3-1: ATA5283 wakeup protocol description

In order to have full compatibility to ATA5283, AS3932 should be set to frequency detection only (R1<1>=0). In

this way the AS3932 will react to the presence of the carrier signal (WAKE signal goes high as soon as the carrier

Version 1.0, Date: 20/02/2009

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