HD6433045 HITACHI [Hitachi Semiconductor], HD6433045 Datasheet - Page 637

• Manufacturer Part Number: HD6433045
• Description: Hitachi Single-Chip Microcomputer
• Manufacturer: HITACHI [Hitachi Semiconductor]

(5) Do not apply 12 V to the V
caused by accidental programming or erasing, apply 12 V to V
programmed or erased, or when flash memory is emulated by RAM. While 12 V is applied, the
watchdog timer should be running and enabled to halt runaway program execution, so that
program runaway will not lead to overprogramming or overerasing.
(6) Disable watchdog-timer reset output (RESO) while the programming voltage (V
on. If 12 V is applied during watchdog timer reset output (while the RESO pin is low), overcurrent
flow will permanently destroy the reset output circuit. The watchdog timers reset output enable bit
(RSTOE) should not be set to 1.
If a pull-up resistor is externally attached to the V
reverse current from flowing to V
(7) If the watchdog timer generates a reset output signal when 12 V is not applied, the rise and
fall of the reset output waveform will be delayed by any decoupling capacitors connected to the
V
PP
pin.
+12 V
Figure 18-31 V
+5 V
1.0 F
PP
CC
Pull-up resistor and
a diode
pin during normal operation. To prevent microcontroller errors
PP
when V
Power Supply Circuit Design (Example)
0.01 F
PP
628
is applied (figure 18-31).
PP
/RESO pin, a diode is necessary to prevent
V
RESO
PP
/
PP
only when the flash memory is
H8/3048F
PP
) is turned