upd78f0114hgb-8es-a Renesas Electronics Corporation., upd78f0114hgb-8es-a Datasheet - Page 106

• Manufacturer Part Number: upd78f0114hgb-8es-a
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

5.4.2 Subsystem clock oscillator
and XT2 pins.
and the inverse signal to the XT2 pin.
106
The subsystem clock oscillator oscillates with a crystal resonator (Standard: 32.768 kHz) connected to the XT1
External clocks can be input to the subsystem clock oscillator. In this case, input the clock signal to the XT1 pin
Figure 5-10 shows examples of the external circuit of the subsystem clock oscillator.
Caution
Note that the subsystem clock oscillator is designed as a low-amplitude circuit for reducing
power consumption.
When using the high-speed system clock oscillator and subsystem clock oscillator, wire as
follows in the area enclosed by the broken lines in Figures 5-8 to 5-10 to avoid an adverse
effect from wiring capacitance.
• Keep the wiring length as short as possible.
• Do not cross the wiring with the other signal lines.
• Do not route the wiring near a signal line through which a high fluctuating current flows.
• Always make the ground point of the oscillator capacitor the same potential as V
• Do not fetch signals from the oscillator.
Figure 5-10. Examples of External Circuit of Subsystem Clock Oscillator
not ground the capacitor to a ground pattern through which a high current flows.
(a) Crystal oscillation
32.768
kHz
CHAPTER 5 CLOCK GENERATOR
V
XT1
XT2
User’s Manual U16961EJ4V0UD
SS
External
clock
(b) External clock
XT1
XT2
SS
. Do