EM78P152S datasheet(26/52 Pages) ETC1

26 / 52 page

EM78P152/3S

8-Bit Microcontroller with OTP ROM

5.7 Oscillator

5.7.1 Oscillator Modes

The EM78P152/3S can be operated in four different oscillator modes, such as External

RC oscillator mode (ERC), Internal RC oscillator mode (IRC), High Crystal oscillator

mode (HXT), and Low Crystal oscillator mode (LXT). The desired mode can be

selected by programming OSC1 and OSC2 in the Code Option register. The Table

below describes how these four oscillator modes are defined.

Table 5-4

Oscillator Modes Defined by OSC

Mode

OSC1

OSC2

IRC (Internal RC oscillator mode)

ERC (External RC oscillator mode)

HXT (High Crystal oscillator mode)

LXT(Low Crystal oscillator mode)

Note: The transient point of system frequency between HXT and LXY is 400kHz.

The maximum operational frequency of the crystal/resonator under different VDD is

listed below.

Table 5-5

Summary of Maximum Operating Speeds

Conditions

VDD

Max Freq. (MHz)

2.3

4.0

3.0

8.0

Two cycles with two clocks

5.0

20.0

5.7.2 Crystal Oscillator/Ceramic Resonators (Crystal)

The EM78P152/3S can be driven by an external clock signal through the OSCI pin as

shown in the following figure.

OSCI

OSCO

EM 78P153S

Ext. Clock

Figure 5-11 Circuit for External Clock Input

•

Product Specification (V1.8) 09.08.2009

(This specification is subject to change without further notice)

EM78P152S 数据表(PDF) 26 Page - List of Unclassifed Manufacturers

EM78P152S 数据表(HTML) 26 Page - List of Unclassifed Manufacturers

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52

数据表下载