UPD784938 Datasheet, PDF (111/733 Pages) NEC – 16-Bit Single-Chip Microcontrollers

CHAPTER 4 CLOCK GENERATOR
4.4 Cautions
The following cautions apply to the clock generator.
4.4.1 When an external clock is input
(1) When an external clock is input, this should be performed with a HCMOS device, or a device with the equivalent drive
capability.
(2) A signal should not be extracted from the X1 and X2 pins. If a signal is extracted, it should be extracted from point a in Figure
4-5.
Figure 4-5. Signal Extraction with External Clock Input
a
µPD74HC04, etc.
µPD784938
X1
X2
(3) The wiring connecting the X1 pin to the X2 pin via an inverter, in particular, should be made as short as possible.
Preliminary User’s Manual U13987EJ1V0UM00
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