H8SXSLASH1663 datasheet(1017/1158 Pages) RENESAS

1017 / 1158 page

Section 22 Clock Pulse Generator

Rev.1.00 Jun. 07, 2006 Page 965 of 1102

REJ09B0294-0100

EXTAL

EXH

EXL

EXr

EXf

Vcc

× 0.5

Figure 22.5 External Clock Input Timing

22.3

PLL Circuit

The PLL circuit has the function of multiplying the frequency of the clock from the oscillator by a

factor of 4. The frequency multiplication rate is fixed. The phase difference is controlled so that

the timing of the rising edge of the internal clock is the same as that of the EXTAL pin signal.

22.4

Frequency Divider

The frequency divider divides the PLL clock to generate a 1/2, 1/4, or 1/8 clock. After the bits

ICK2 to ICK0, PCK 2 to PCK0, and BCK2 to BCK0 are updated, this LSI operates with the

updated frequency.

22.5

Subclock Oscillator

22.5.1

Connecting 32.768 kHz Crystal Resonator

To supply a clock to the subclock oscillator, connect a 32.768-kHz crystal resonator, as shown in

figure 22.6. The usage notes given in section 22.6.3, Notes on Board Design, apply to the

connection of this crystal resonator.

OSC1

OSC2

C1 = C2 = 15 pF (typ.)

Note: C1 and C2 are reference values that include the floating

capacitance of the board.

Figure 22.6 Connection Example of 32.768-kHz Crystal Resonator

H8SX/1663 Datasheet(PDF) 1017 Page - Renesas Technology Corp