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AS3930

Datasheet - Detailed Descri p ti on

8.8.3 External Clock Source

To clock the AS3930 with an external signal the crystal oscillator has to be enabled (R1<0>=1). As shown in Figure 3, the clock must be applied

on the pin XIN while the pin XOUT must stay floating. The RC time constant has to be 100μs with a tolerance of ±10% (e.g. R=680 k

Ω and

C=22pF). In Table 25, the clock characteristics are summarized.

Note:

Table 25. Characteristics of External Clock

Symbol

Parameter

Min

Typ

Max

Units

VI

Low level

0

V

Vh

High level

V

Tr

Rise-time

3

µs

Tf

Fall-time

3

µs

T=1/2

πRC

RC Time constant

90

100

110

µs