PIC10F202 Microchip Technology Inc., PIC10F202 Datasheet - Page 50

• Manufacturer Part Number: PIC10F202
• Description: 6-pin, 8-bit Flash Microcontrollers Data Sheet
• Manufacturer: Microchip Technology Inc.

PIC10F200/202/204/206
9.7
The TO, PD, GPWUF and CWUF bits in the STATUS
register can be tested to determine if a Reset condition
has been caused by a power-up condition, a MCLR,
Watchdog Timer (WDT) Reset, wake-up on comparator
change or wake-up on pin change.
TABLE 9-5:
9.8
A Brown-out Reset is a condition where device power
(V
and then recovers. The device should be reset in the
event of a brown-out.
To reset PIC10F200/202/204/206 devices when a
Brown-out Reset occurs, external brown-out protection
circuits may be built, as shown in Figure 9-7 and
Figure 9-8.
FIGURE 9-7:
DS41239D-page 48
Legend: u = unchanged, x = unknown, – = unimplemented bit, read as ‘0’, q = value depends on condition.
Note 1:
Note 1:
DD
CWUF
) dips below its minimum value, but not to zero,
0
0
0
0
0
0
1
33k
2:
V
Time-out Sequence, Power-down
and Wake-up from Sleep Status
Bits (TO, PD, GPWUF, CWUF)
Reset on Brown-out
DD
The TO, PD, GPWUF and CWUF bits maintain their status (u) until a Reset occurs. A low-pulse on the
MCLR input does not change the TO, PD, GPWUF or CWUF Status bits.
This circuit will activate Reset when V
below Vz + 0.7V (where Vz = Zener voltage).
Pin must be confirmed as MCLR.
10k
TO, PD, GPWUF, CWUF STATUS AFTER RESET
GPWUF
0
0
0
0
0
1
0
BROWN-OUT
PROTECTION CIRCUIT 1
Q1
40k
MCLR
(1)
V
DD
(2)
PIC10F20X
TO
0
0
1
1
u
1
1
DD
goes
PD
0
u
0
1
u
0
0
WDT wake-up from Sleep
WDT time-out (not from Sleep)
MCLR wake-up from Sleep
Power-up
MCLR not during Sleep
Wake-up from Sleep on pin change
Wake-up from Sleep on comparator change
FIGURE 9-8:
Note 1:
R1
R2
V
2:
DD
This brown-out circuit is less expensive,
although less accurate. Transistor Q1 turns
off when V
that:
Pin must be confirmed as MCLR.
Reset Caused By
V
DD
•
BROWN-OUT
PROTECTION CIRCUIT 2
DD
© 2007 Microchip Technology Inc.
Q1
40k
V
is below a certain level such
R1 + R2
DD
MCLR
(1)
R1
(2)
PIC10F20X
= 0.7V