HMS87C1304A Datasheet, PDF (60/70 Pages) Hynix Semiconductor – CMOS SINGLE-CHIP 8-BIT MICROCONTROLLER

HMS87C1304A/HMS87C1302A
HYUNDAI MicroElectronics
Oscillator
(X_IN pin)
RCWDT Mode
Internal
RC Clock
Internal
Clock
RESET
RESET by WDT
Internal
RESET
STOP Instruction Execution
Time can not be controlled by software
Stabilization Time
t_ST = 64mS @4MHz
INPUT PIN
V_DD
i
GND
X
Weak pull-up current flows
Figure 17-6 Internal RCWDT Mode Releasing by RESET.
y _VDD
V_DD
r _internal
a ^pull-up
INPUT PIN
OPEN
i
V_DD
i=0
O _limin ^O _VDD
Pr^{Oe X O OPEN}
Very weak current flows
i=0
GND
When port is configured as an input, input level should
be closed to 0V or 5V to avoid power consumption.
Figure 17-7 Application Example of Unused Input Por
t
OUTPUT PIN
ON
OFF _i
GND
X
ON
OPEN
OFF
O
V_DD
ON
O ^OFF
In the left case, much current flows from port to GND.
OUTPUT PIN
ON
V_DD
L
OFF
V_DD
L
OFF _i
GND
ON i=0
GND
X
O
In the left case, Tr. base current flows from port to GND.
To avoid power consumption, there should be low output
to the port .
Figure 17-8 Application Example of Unused input Port
60
Preliminary
Jan. 2001