EM78P510N
8-Bit Microcontrollers
In most applications, pin R-OSCI and pin OSCO can be connected with a crystal or
ceramic resonator to generate oscillation. Fig. 6-7 depicts such circuitry. Table 5
provides the recommended values of C1 and C2. Since each resonator has its own
attribute, user should refer to its specification for appropriate values of C1 and C2. RS,
a serial resistor, may be necessary for AT strip cut crystal or low frequency mode.
Fig. 6-7 Circuit for Crystal/Resonator
Table 5 Capacitor Selection Guide for Crystal Oscillator or Ceramic Resonators
Oscillator Source
Main oscillator
Sub-oscillator
Oscillator Type
Frequency
455kHz
C1 (pF)
100~150
20~40
10~30
20~40
15~30
15
C2 (pF)
100~150
20~40
10~30
20~150
15~30
15
Ceramic Resonators
2.0 MHz
4.0 MHz
455kHz
1.0MHz
Crystal Oscillator
Crystal Oscillator
2.0MHz
4.0MHz
15
15
32.768kHz
25
25
330
330
C
OSCI
7404
7404
7404
Crystal
Fig. 6-8 Circuit for Crystal/Resonator-Series Mode
Product Specification (V0.9) 09.12.2006
(This specification is subject to change without further notice)
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ELAN [ ELAN MICROELECTRONICS CORP ]
