PIC16F57-I/P Microchip Technology, PIC16F57-I/P Datasheet - Page 29

• Manufacturer Part Number: PIC16F57-I/P
• Description: IC MCU FLASH 2KX12 28DIP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F57-I/P

• Program Memory Type: FLASH
• Program Memory Size: 3KB (2K x 12)
• Package / Case: 28-DIP (0.600", 15.24mm)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Peripherals: POR, WDT
• Number Of I /o: 20
• Ram Size: 72 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 72 B
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 20
• Number Of Timers: 1
• Operating Supply Voltage: 2 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734
• Development Tools By Supplier: DV164120, DV164101, ICE2000
• Minimum Operating Temperature: - 40 C
• Data Rom Size: 2 K
• Height: 3.3 mm
• Length: 34.67 mm
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2 V
• Width: 7.24 mm
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: XLT28XP - SOCKET TRANSITION ICE 28DIPAC164001 - MODULE SKT PROMATEII 18/28DIP
• Eeprom Size: -
• Data Converters: -
• Connectivity: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

5.2
The Device Reset Timer (DRT) provides an 18 ms
nominal time-out on Reset regardless of the oscillator
mode used. The DRT operates on an internal RC
oscillator. The processor is kept in Reset as long as the
DRT is active. The DRT delay allows V
V
Oscillator circuits, based on crystals or ceramic resona-
tors, require a certain time after power-up to establish
a stable oscillation. The on-chip DRT keeps the device
in a Reset condition for approximately 18 ms after the
voltage on the MCLR/V
(V
the MCLR input are not required in most cases,
allowing for savings in cost-sensitive and/or space
restricted applications.
The device Reset time delay will vary from chip-to-chip
due to V
AC parameters for details.
The DRT will also be triggered upon a Watchdog Timer
time-out. This is particularly important for applications
using the WDT to wake the PIC16F5X from Sleep
mode automatically.
5.3
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 PIC16F5X devices when a Brown-out occurs,
external Brown-out protection circuits may be built, as
shown in Figure 5-6, Figure 5-7 and Figure 5-8.
FIGURE 5-6:
© 2007 Microchip Technology Inc.
This circuit will activate Reset when V
Vz + 0.7V (where Vz = Zener voltage).
DD
IH
) level. Thus, external RC networks connected to
min. and for the chosen oscillator to stabilize.
33k
V
Device Reset Timer (DRT)
DD
Reset on Brown-Out
DD
, temperature and process variation. See
10k
EXTERNAL BROWN-OUT
PROTECTION CIRCUIT 1
PP
Q1
40k
pin has reached a logic high
MCLR
PIC16F5X
V
DD
DD
DD
goes below
to rise above
DD
)
FIGURE 5-7:
FIGURE 5-8:
V
This brown-out circuit is less expensive, although
less accurate. Transistor Q1 turns off when V
below a certain level such that:
This
Microchip Technology’s MCP809 microcontroller
supervisor. The MCP8XX and MCP1XX families
of supervisors provide push-pull and open collec-
tor outputs with both “active-high and active-low”
Reset pins. There are 7 different trip point
selections to accommodate 5V and 3V systems.
SS
MCP809
V
DD
brown-out
V
R1
R2
DD
RST
V
DD
V
DD
Capacitor
•
Bypass
protection
EXTERNAL BROWN-OUT
PROTECTION CIRCUIT 2
EXTERNAL BROWN-OUT
PROTECTION CIRCUIT 3
R1 + R2
R1
Q1
PIC16F5X
40k
= 0.7V
circuit
MCLR
PIC16F5X
V
DS41213D-page 27
DD
MCLR
V
PIC16F5X
DD
employs
DD
is