PIC16C505-20I/P Microchip Technology, PIC16C505-20I/P Datasheet - Page 36

• Manufacturer Part Number: PIC16C505-20I/P
• Description: IC MCU OTP 1KX12 14DIP
• Manufacturer: Microchip Technology
• Series: PIC® 16Cr

Specifications of PIC16C505-20I/P

• Core Size: 8-Bit
• Program Memory Size: 1.5KB (1K x 12)
• Oscillator Type: Internal
• Core Processor: PIC
• Speed: 20MHz
• Peripherals: POR, WDT
• Number Of I /o: 11
• Program Memory Type: OTP
• Ram Size: 72 x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 14-DIP (0.300", 7.62mm)
• Controller Family/series: PIC16C
• No. Of I/o's: 12
• Ram Memory Size: 72Byte
• Cpu Speed: 20MHz
• No. Of Timers: 1
• Digital: RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: ISPICR1 - ADAPTER IN-CIRCUIT PROGRAMMING309-1086 - ADAPTER 14-ZIF BD W/14-SO PLUGS309-1085 - ADAPTER 14-DIP BD W/2 14-SO PLUGAC124001 - MODULE SKT PROMATEII 8DIP/SOIC
• Eeprom Size: -
• Data Converters: -
• Connectivity: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PIC16C505
7.7
The TO, PD, and 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 7-7:
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 PIC16C505 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: BROWN-OUT PROTECTION
DS40192C-page 36
RBWUF TO
Legend: u = unchanged
Note 1: The TO, PD, and RBWUF bits maintain their
This circuit will activate reset when V
Vz + 0.7V (where Vz = Zener voltage).
Note 1: Pin must be confirmed as MCLR.
0
0
0
0
0
1
33k
V
Time-Out Sequence, Power Down,
and Wake-up from SLEEP Status Bits
(TO/PD/RBWUF)
Reset on Brown-Out
status (u) until a reset occurs. A low-pulse on the
MCLR input does not change the TO, PD, and
RBWUF status bits.
DD
0
0
1
1
u
1
10k
PD
TO/PD/RBWUF STATUS
AFTER RESET
CIRCUIT 1
0
u
0
1
u
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
Q1
40k*
MCLR
V
RESET caused by
DD
(1)
DD
PIC16C505
goes below
DD
)
FIGURE 7-13: BROWN-OUT PROTECTION
FIGURE 7-14: BROWN-OUT PROTECTION
This brown-out circuit is less expensive, although
less accurate. Transistor Q1 turns off when V
is below a certain level such that:
Note 1: Pin must be confirmed as MCLR.
This brown-out protection circuit employs Microchip
Technology’s
There
accommodate 5V to 3V systems.
V
SS
MCP809
RST
are
R1
R2
V
DD
V
7
V
V
DD
MCP809
DD
DD
CIRCUIT 2
CIRCUIT 3
different
capacitor
•
bypass
R1 + R2
1999 Microchip Technology Inc.
R1
microcontroller
trip
Q1
40k*
V
DD
MCLR
point
= 0.7V
V
PIC12C5XX
DD
(1)
selections
PIC16C505
MCLR
supervisor.
DD
to