PIC16F818-I/P Microchip Technology, PIC16F818-I/P Datasheet - Page 512

• Manufacturer Part Number: PIC16F818-I/P
• Description: IC MCU FLASH 1KX14 18-DIP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F818-I/P

• Program Memory Type: FLASH
• Program Memory Size: 1.75KB (1K x 14)
• Package / Case: 18-DIP (0.300", 7.62mm)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 16
• Eeprom Size: 128 x 8
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 5x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 128 B
• Interface Type: I2C/SPI/SSP
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 16
• Number Of Timers: 3
• 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: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, DM163014
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 5-ch x 10-bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: ACICE0202 - ADAPTER MPLABICE 18P 300 MILAC164010 - MODULE SKT PROMATEII DIP/SOIC
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

PICmicro MID-RANGE MCU FAMILY
28.3
DS31028A-page 28-4
Application Circuit
The application circuit must be designed to allow all the programming signals to be directly con-
nected to the PICmicro MCU.
designing with ICSP. The application must compensate for the following issues:
• Isolation of the MCLR/V
• Loading of pins RB6 and RB7
• Capacitance on each of the V
• Minimum and maximum operating voltage for V
• PICmicro Oscillator
• Interface to the programmer
The MCLR/V
a capacitor is tied to ground. This circuit can affect the operation of ICSP depending on the size
of the capacitor since the V
a resistor is not capable of isolating the circuit). It is, therefore, recommended that the circuit in
Figure 28-1
tky-type device. Another issue with MCLR/V
this pin is driven to approximately 13V and also to ground. Therefore, the application circuit must
be isolated from this voltage provided by the programmer.
Pins RB6 and RB7 are used by the PICmicro for serial programming. RB6 is the clock line and
RB7 is the data line. RB6 is driven by the programmer. RB7 is a bi-directional pin that is driven
by the programmer when programming, and driven by the PICmicro when verifying. These pins
must be isolated from the rest of the application circuit so as not to affect the signals during pro-
gramming. You must take into consideration the output impedance of the programmer when iso-
lating RB6 and RB7 from the rest of the circuit. This isolation circuit must account for RB6 being
an input on the PICmicro, and for RB7 being bi-directional (can be driven by both the PICmicro
and the programmer). For instance, PRO MATE
design permits, these pins should not be used by the application. This is not the case with most
applications so it is recommended that the designer evaluate whether these signals need to be
buffered. As a designer, you must consider what type of circuitry is connected to RB6 and RB7
and then make a decision on how to isolate these pins.
to isolate RB6 and RB7 on the application circuit because this is very application dependent.
To simplify this interface the optimal usage of these I/O in the application are (in order):
1.
2.
3.
Figure 28-1: Typical In-Circuit Serial Programming (ICSP) Application Circuit
Do not use RB6/RB7 so they are dedicated to ICSP.
Use these pins as outputs with minimal loading on signal line.
Isolation circuitry so that these signals can be driven to the ICSP specifications.
PIC16CXXX
be used when an RC is connected to MCLR/V
PP
To application circuit
pin is normally connected to an RC circuit. The pull-up resistor is tied to V
Application PCB
MCLR/V
V
V
RB7
RB6
DD
SS
PP
PP
PP
pin from the rest of the circuit
Figure 28-1
voltage must be isolated from the rest of the circuit (in most cases
DD
, MCLR/V
Isolation circuits
V
shows a typical circuit that is a starting point for when
DD
PP
PP
is that when the PICmicro device is programmed,
, RB6, and RB7 pins
V
DD
®
DD
II has an output impedance of 1k . If the
Figure 28-1
PP
ICSP Connector
. The diode should be a Schot-
1997 Microchip Technology Inc.
does not show any circuitry
DD
and