Datasheet
Section 23 Electrical Characteristics 
    Rev. 3.00 Mar. 15, 2006 Page 459 of 526 
   REJ09B0060-0300 
23.3.7  Power-On Reset Circuit Characteristics (Optional) 
Table 23.18  Power-On Reset Circuit Characteristics 
V
SS 
= 0.0 V, T
a
 = –20 to +75°C, unless otherwise indicated. 
Values 
Item Symbol 
Test 
Condition 
Min. Typ. Max. Unit 
Pull-up resistance of RES pin R
RES
  100 150  kΩ 
Power-on reset start voltage* V
por
       100 mV 
Note:  *  The power-supply voltage (Vcc) must fall below Vpor = 100 mV and then rise after 
charge of the RES pin is removed completely. In order to remove charge of the RES 
pin, it is recommended that the diode be placed in the Vcc side. If the power-supply 
voltage (Vcc) rises from the point over 100 mV, a power-on reset may not occur. 
23.4 Operation Timing 
t
OSC
V
IH
V
IL
t
CPH
t
CPL
t
CPr
OSC1
t
CPf
Figure 23.1 System Clock Input Timing 
t
REL
V
IL
RES
t
REL
V
IL
V
CC
 × 0.7
V
CC
OSC1
Figure 23.2 RES Low Width Timing 










