4513_03 Datasheet, PDF (166/210 Pages) Renesas Technology Corp – 4-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.10 Oscillation circuit
2.10 Oscillation circuit
The 4513/4514 Group has an internal oscillation circuit to produce the clock required for microcomputer
operation.
The clock signal f(XIN) is obtained by connecting a ceramic resonator to XIN pin and XOUT pin.
2.10.1 Oscillation circuit
(1) f(XIN) clock generating circuit
The clock signal f(XIN) is obtained by connecting a ceramic resonator externally.
Connect this external circuit to pins XIN and XOUT at the shortest distance. A feed-back resistor is
built-in between XIN pin and XOUT pin.
Figure 2.10.1 shows an example of an oscillation circuit connecting a ceramic resonator externally.
Keep the maximum value of oscillation frequency within the range listed Table 2.10.1.
Table 2.10.1 Maximum value of oscillation frequency and supply voltage
Supply voltage
(System clock)
Oscillation frequency
2.5 V to 5.5 V
(f(XIN)/2) Middle-speed mode
4.2 MHz
4.0 V to 5.5 V
(f(XIN)) High-speed mode
4.2 MHz
2.5 V to 5.5 V
(f(XIN)) High-speed mode
2.0 MHz
2.0 V to 5.5 V (Note) (f(XIN)/2) Middle-speed mode
3.0 MHz
2.0 V to 5.5 V (Note) (f(XIN)) High-speed mode
1.5 MHz
Note: 2.5 V to 5.5 V for the One Timer PROM version.
4513/4514
Note: Externally connect a
damping resistor Rd de-
XIN
XOUT
pending on the oscilla-
tion frequency. (A feed-
back resistor is built-in.)
Rd
Use the resonator
manufacturer’s recom-
mended value because
CIN
COUT
constants such as ca-
pacitance depend on the
resonator.
Fig. 2.10.1 Oscillation circuit example connecting
ceramic resonator externally
4513/4514 Group User’s Manual
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