Datasheet

R8C/2E Group, R8C/2F Group 5. Electrical Characteristics
Rev.1.00 Dec 14, 2007 Page 29 of 39
REJ03B0222-0100
NOTES:
1. The measurement condition is T
opr = −20 to 85°C (N version) / −40 to 85°C (D version), unless otherwise specified.
2. This condition (external power V
CC rise gradient) does not apply if VCC ≥ 1.0 V.
3. t
w(por1) indicates the duration the external power VCC must be held below the effective voltage (Vpor1) to enable a power on
reset. When turning on the power for the first time, maintain t
w(por1) for 30 s or more if −20°C ≤ Topr ≤ 85°C, maintain tw(por1) for
3,000 s or more if −40°C ≤ T
opr < −20°C.
Figure 5.3 Reset Circuit Electrical Characteristics
Table 5.10 Power-on Reset Circuit, Voltage Monitor 0 Reset Electrical Characteristics
Symbol Parameter Condition
Standard
Unit
Min. Typ. Max.
V
por1
Power-on reset valid voltage
(3)
−−0.1 V
V
por2 Power-on reset valid voltage 0 − 2.6 V
t
rth
External power VCC rise gradient
(2)
20 −−mV/msec
NOTES:
1. Ensure that the voltage is 2.2 V or above during the sampling time.
2. The sampling time is fOCO-S divided by 1 × 4 cycles.
max. 2.6 V
V
por1
Internal
reset signal
(“L” valid)
t
w(por1)
Sampling time
(1, 2)
max. 2.6 V
1
f
OCO-S
× 32
1
f
OCO-S
× 32
Vpor2
2.2 V
External
Power V
CC
trth
trth