FX604 Datasheet, PDF (5/17 Pages) Sanyo Semicon Device – Ultrahigh-Speed Switching Applications

V.23 Compatible Modem
1.4 External Components
FX604
R1
100kΩ
X1
3.579545MHz
C1, C2
C3
C4
18pF
0.1µF
0.1µF
Resistors ±5%, capacitors ±10% unless otherwise stated.
Figure 2 Recommended External Components for Typical Application
1.5 General Description
1.5.1 Xtal Osc and Clock Dividers
Frequency and timing accuracy of the FX604 is determined by a 3.579545MHz clock present at the
XTAL/CLOCK pin. This may be generated by the on-chip oscillator inverter using the external components C1,
C2 and X1 of Figure 2, or may be supplied from an external source to the XTAL/CLOCK input. If supplied from
an external source, C1, C2 and X1 should not be fitted.
The on-chip oscillator is turned off in the 'Zero-Power' mode.
If the clock is provided by an external source which is not always running, then the 'Zero-Power' mode must be
set when the clock is not available. Failure to observe this rule may cause a significant rise in the supply
current drawn by FX604 as well as generating undefined states of the RXD, DET and RDYN outputs.
© 1996 Consumer Microcircuits Limited
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