PIC16F506 Microchip Technology, PIC16F506 Datasheet - Page 70

• Manufacturer Part Number: PIC16F506
• Description: (PIC12F510 / PIC16F506) 8-Bit Flash Microcontroller
• Manufacturer: Microchip Technology

PIC12F510/16F506
10.7
The TO, PD and (GPWUF/RBWUF) bits in the STATUS
register can be tested to determine if a Reset condition
has been caused by a power-up condition, a MCLR or
Watchdog Timer (WDT) Reset.
TABLE 10-8:
10.8
A brown-out is a condition where device power (V
dips below its minimum value, but not to zero, and then
recovers. The device should be reset in the event of a
brown-out.
To reset PIC12F510/16F506 devices when a brown-
out occurs, external brown-out protection circuits may
be built, as shown in Figure 10-13 and Figure 10-14.
FIGURE 10-13:
DS41268B-page 68
CWUF
Legend: u = unchanged
Note 1:
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/RBWUF)
Reset on Brown-out
GPWUF/
RBWUF
DD
This circuit will activate Reset when V
below Vz + 0.7V (where Vz = Zener voltage).
Pin must be configured as MCLR.
0
0
0
0
0
1
0
10k
TO/PD/(GPWUF/RBWUF)
STATUS AFTER RESET
TO PD
0
0
1
1
u
1
1
BROWN-OUT
PROTECTION CIRCUIT 1
Q1
40k
0
u
0
1
u
0
0
MCLR
(1)
V
DD
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
Reset Caused By
(2)
PIC12F510
PIC16F506
DD
goes
Preliminary
DD
)
FIGURE 10-14:
FIGURE 10-15:
Note 1:
Note:
V
2:
SS
MCP809
RST
R1
R2
This brown-out circuit is less expensive,
although less accurate. Transistor Q1 turns
off when V
that:
Pin must be configured as MCLR.
This brown-out protection circuit employs
Microchip Technology’s MCP809 microcon-
troller supervisor. There are 7 different trip
point selections to accommodate 5V to 3V
systems.
V
DD
V
V
V
DD
DD
DD
Capacitor
•
Bypass
DD
BROWN-OUT
PROTECTION CIRCUIT 2
BROWN-OUT
PROTECTION CIRCUIT 3
R1 + R2
© 2006 Microchip Technology Inc.
is below a certain level such
R1
Q1
40k
V
DD
MCLR
(1)
= 0.7V
V
PIC12F510
PIC16F506
DD
(2)
PIC12F510
PIC16F506
MCLR