Z8FMC04100 ZILOG [Zilog, Inc.], Z8FMC04100 Datasheet - Page 259

• Manufacturer Part Number: Z8FMC04100
• Description: Z8 Encore-R Motor Control Flash MCUs
• Manufacturer: ZILOG [Zilog, Inc.]

On-Chip Oscillator
PS024604-1005
Crystal Oscillator Operation
The products in the Z8FMC16100 Series Flash MCU features an on-chip oscillator for use
with external crystals with frequencies ranging from 32 KHz to 20 MHz. In addition, the
oscillator can support ceramic resonators with oscillation frequencies up to 20 MHz. This
oscillator generates the primary system clock for the internal eZ8 CPU and the majority of
the on-chip peripherals. Alternatively, the X
clock input signal (32 KHz–20 MHz). If an external clock generator is used, the X
must remain unconnected.
When configured for use with crystal oscillators or external clock drivers, the frequency of
the signal on the X
internal clock divider).
Figure 40 illustrates a recommended configuration for connection with an external funda-
mental-mode, parallel-resonant crystal operating at 20 MHz. Recommended 20 MHz crys-
tal specifications are provided in Table 132. The printed circuit board layout must add no
more than 4 pF of stray capacitance to either the X
occur, reduce the values of capacitors C1 and C2 to decrease loading.
Figure 40. Recommended 20MHz Crystal Oscillator Configuration
C = 22 pF
2
X
IN
IN
input pin determines the frequency of the system clock (that is, no
(Fundamental Mode)
On-Chip Oscillator
20 MHz Crystal
P R E L I M I N A R Y
IN
input pin can also accept a CMOS-level
IN
X
OUT
Z8FMC16100 Series Flash MCU
or X
C = 22 pF
2
OUT
pins. If oscillation does not
Product Specification
Crystal Oscillator Operation
OUT
pin
237