PIC16F505T-I/MG Microchip Technology, PIC16F505T-I/MG Datasheet - Page 54

• Manufacturer Part Number: PIC16F505T-I/MG
• Description: 1.5 KB Flash, 72 RAM, 12 I/O 16 QFN 3x3x0.9mm T/R
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F505T-I/MG

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Peripherals: POR, WDT
• Number Of I /o: 11
• Program Memory Size: 1.5KB (1K x 12)
• Program Memory Type: FLASH
• Ram Size: 72 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 16-QFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Connectivity: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PIC12F508/509/16F505
7.7
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 7-8:
7.8
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 PIC12F508/509/16F505 devices when a
brown-out occurs, external brown-out protection
circuits may be built, as shown in Figure 7-12 and
Figure 7-13.
FIGURE 7-12:
DS41236E-page 54
Legend: u = unchanged
Note 1:
Note 1:
GPWUF/
RBWUF
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
DD
The TO, PD and GPWUF/RBWUF bits
maintain their status (u) until a Reset
occurs. A low-pulse on the MCLR input
does not change the TO, PD and
GPWUF/RBWUF Status bits.
This circuit will activate Reset when V
below Vz + 0.7V (where Vz = Zener voltage).
Pin must be confirmed as MCLR.
TO
0
0
1
1
u
1
10k
TO/PD/(GPWUF/RBWUF)
STATUS AFTER RESET
PD
0
u
0
1
u
0
BROWN-OUT
PROTECTION CIRCUIT 1
Q1
40k
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
MCLR
(1)
V
Reset Caused By
DD
(2)
PIC16F505
PIC12F508
PIC12F509
DD
goes
DD
)
FIGURE 7-13:
FIGURE 7-14:
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 confirmed as MCLR.
V
This brown-out protection circuit employs
Microchip Technology’s MCP809 micro-
controller supervisor. There are 7 different
trip point selections to accommodate 5V to
3V systems.
DD
V
V
V
DD
DD
DD
Capacitor
•
Bypass
DD
BROWN-OUT
PROTECTION CIRCUIT 2
BROWN-OUT
PROTECTION CIRCUIT 3
R1 + R2
© 2009 Microchip Technology Inc.
is below a certain level such
R1
Q1
40k
V
DD
MCLR
(1)
= 0.7V
V
PIC16F505
PIC12F508
PIC12F509
DD
(2)
PIC16F505
PIC12F508
PIC12F509
MCLR