HT85F2270 datasheet(59/226 Pages) HOLTEK

59 / 226 page

Rev. 1.00

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Standard 8051 8-Bit Flash MCU

HT85F2260/HT85F2270/HT85F2280

To i nt er na l

ci rc ui ts

In te rn al

O sc illa to r

Ci rc ui t

In te r nal R C

Os c illa to r

32768 Hz

External LXT Oscillator – LXT

32768Hz Crystal Recommended Capacitor Values

LXT Oscillator C1 and C2 Values

Crystal Frequency

��768Hz

10pF

Note: C1 and C� values are for guidance onl�.

Internal Low Speed RC Oscillator – LIRC

The internal low speed oscillator, LIRC, is a fully self-contained free running on-chip RC

oscillator, used as a clock source for the Watchdog Timer and the Time Base functions. When

the microcontroller enters the IDLE Mode, the CPU clock is switched off to stop microcontroller

activity and to conserve power, however the LIRC oscillator will continue to run and can maintain

WDT and Time Base operation if it is selected as their clock source. The LIRC oscillator has

a typical frequency of 32kHz at 5V and requires no external components, however its actual

frequency may vary with temperature and supply voltage. For precise low speed oscillator

functions the LXT oscillator should be used.

HT85F2270 Datasheet(PDF) 59 Page - Holtek Semiconductor Inc