saf-xc878m-16ffi5v Infineon Technologies Corporation, saf-xc878m-16ffi5v Datasheet - Page 85

• Manufacturer Part Number: saf-xc878m-16ffi5v
• Description: 8-bit Single-chip Microcontroller
• Manufacturer: Infineon Technologies Corporation

resistance method. Oscillation measurement with the final target system is strongly
recommended to verify the input amplitude at XTAL1 and to determine the actual
oscillation allowance (margin negative resistance) for the oscillator-crystal system.
When using an external clock signal, the signal must be connected to XTAL1. XTAL2 is
left open (unconnected).
The oscillator can also be used in combination with a ceramic resonator. The final
circuitry must also be verified by the resonator vendor.
recommended external oscillator circuitries for both operating modes, external crystal
mode and external input clock mode.
Figure 21
Note: For crystal operation, it is strongly recommended to measure the negative
Data Sheet
2 - 20
Fundamental
Mode Crystal
MHz
C
resistance in the final target system (layout) to determine the optimum parameters
for the oscillator operation. Please refer to the minimum and maximum values of
the negative resistance specified by the crystal supplier.
X1
R
Q
C
R
External Oscillator Circuitry
R
X2
X2
f
XTAL1
XTAL2
Oscillator
XC87x
V
SS
f
OSC
78
External Clock
Signal
XTAL1
XTAL2
Functional Description
Figure 21
Oscillator
XC87x
V
SS
XC87xCLM
V1.5, 2011-03
shows the
f
OSC