PCA84C441 PHILIPS [NXP Semiconductors], PCA84C441 Datasheet - Page 8

• Manufacturer Part Number: PCA84C441
• Description: 8-bit microcontrollers with OSD and VST
• Manufacturer: PHILIPS [NXP Semiconductors]

andbook, halfpage
Philips Semiconductors
7
The RESET pin (active LOW input) is used to initialize the
microcontroller to a defined state. The Reset configuration
is shown in Fig.5.
1996 Nov 29
handbook, full pagewidth
8-bit microcontrollers with OSD and VST
RESET
Fig.4 External components for RESET pin.
RESET
R 100 k
C
MCD174
V
ref
internal
reset
V
V SS
DD
POWER-ON-RESET
Fig.5 Reset configuration.
oscillator
inhibit
8
7.1
The Power-on-reset circuit monitors the voltage level of
V
level V
When V
the internal reset is active for a period of t
50 s).
Considering the V
a correct Power-on-reset can be taken:
A definite Power-on-reset can be realized by applying an
(external) RESET signal during power-on.
DD
If the V
before time period t
components are necessary (see Fig.6).
If V
period (t
below the minimum operation voltage (V
external components are required (see Figs 4 and 7).
To guarantee a correct reset operation, ensure that the
time constant RC
. If V
DD
ref
Power-on-reset
DD
DD
has a slow rise time, such that after the time
(typically 1.3 V), the oscillator is inhibited.
DD
Vref
rises above V
remains below the internal reference voltage
rises above the minimum operation voltage
+ t
84C44X; 84C64X; 84C84X
MLA651
d
) has elapsed the supply voltage is still
DD
rise time, the following measures for
d
8
is exceeded, no external
ref
t
VDD
V
, the oscillator is released and
V
RESET
SS
DD
.
Product specification
d
min
(typically
),