H8SSLASH2214 datasheet(669/936 Pages) RENESAS

Il numero della parte	H8S/2214

Spiegazioni elettronici	16-Bit Single-Chip Microcomputer H8S Family/H8S/2200 Series

PDF	936 Pages

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Produttore elettronici	RENESAS [Renesas Technology Corp]

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Section 16 Clock Pulse Generator

Rev.4.00 Sep. 18, 2008 Page 609 of 872

REJ09B0189-0400

16.3

System Clock Oscillator

Clock pulses can be supplied by connecting a crystal resonator, or by input of an external clock.

16.3.1

Connecting a Crystal Resonator

(1) Circuit Configuration

A crystal resonator can be connected as shown in the example in figure 16.2. Select the damping

resistance R

d according to table 16.2. An AT-cut parallel-resonance crystal should be used.

EXTAL

XTAL

CL2

CL1

CL1 = CL2 = 10 to 22 pF

Figure 16.2 Connection of Crystal Resonator (Example)

Table 16.2

Damping Resistance Value

Frequency (MHz) 2

d (Ω)

1 k

500

300

200

100

(2) Crystal Resonator

Figure 16.3 shows the equivalent circuit of the crystal resonator. Use a crystal resonator that has

the characteristics shown in table 16.3 and the same resonance frequency as the system clock (

φ).

XTAL

AT-cut parallel-resonance type

EXTAL

LRs

Figure 16.3 Crystal Resonator Equivalent Circuit

H8S/2214 Scheda tecnica(PDF) 669 Page - Renesas Technology Corp