UPD78F0890GK(A)-GAJ-AX NEC, UPD78F0890GK(A)-GAJ-AX Datasheet - Page 137

• Manufacturer Part Number: UPD78F0890GK(A)-GAJ-AX
• Description: 8BIT MCU, 128K FLASH, 7K RAM, LQFP
• Manufacturer: NEC

Specifications of UPD78F0890GK(A)-GAJ-AX

• Controller Family/series: UPD78F
• No. Of I/o's: 55
• Ram Memory Size: 7KB
• Cpu Speed: 20MHz
• No. Of Timers: 10
• No. Of Pwm: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 128KB
• Oscillator Type: External, Internal

6.4 System Clock Oscillator
6.4.1 X1 oscillator
pins.
6.4.2 XT1 oscillator
The X1 oscillator oscillates with a crystal resonator or ceramic resonator (4 to 20 MHz) connected to the X1 and X2
An external clock can also be input. In this case, input the clock signal to the EXCLK pin.
Figure 6-9 shows an example of the external circuit of the X1 oscillator.
Cautions are listed on the next page.
The XT1 oscillator oscillates with a crystal resonator (standard: 32.768 kHz) connected to the XT1 and XT2 pins.
An external clock can also be input. In this case, input the clock signal to the EXCLKS pin.
Figure 6-10 shows an example of the external circuit of the XT1 oscillator.
Caution is listed on the next page.
(a) Crystal or ceramic oscillation
Crystal resonator
or
ceramic resonator
(a) Crystal oscillation
Figure 6-10. Example of External Circuit of XT1 Oscillator
Figure 6-9. Example of External Circuit of X1 Oscillator
32.768
kHz
V
X1
X2
SS
V
XT1
XT2
SS
CHAPTER 6 CLOCK GENERATOR
User’s Manual U17554EJ4V0UD
External clock
External clock
(b) External clock
(b) External clock
EXCLK
EXCLKS
137