PRELIMINARY
CYW20710
6.2 Crystal Oscillator
The CYW20710 can use an external crystal to provide a frequency reference. The recommended configuration for the crystal oscillator,
including all external components, is shown in Figure 6.
Figure 6. Recommended Oscillator Configuration
XIN
0 to 18 pF*
Crystal
Oscillator
XOUT
0 to 18 pF*
*Capacitor value range depends
on the manufacturer of the XTAL
as well as board layout.
6.3 External Frequency Reference
An external frequency reference generated by a TCXO signal that may be directly connected to the crystal input pin on the CYW20710,
as shown in Figure 7. The external frequency reference input is designed to not change loading on the TCXO when the CYW20710
is powered up or powered down.
When using the CYW20710 with the TXCO OR gate option, GPIO 6 must be driven active high or active low. Excessive leakage
current results if GPIO6 is allowed to float.
Figure 7. Recommended TCXO Connection
TCXO
XIN
10–1000 pF*
No Connection
XOUT
* Recommended value is 100 pF.
Higher values produce a longer startup time.
Lower values have greater isolation.
Larger values help small signal swings.
Document No. 002-14804 Rev. *H
Page 22 of 50
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