DV164121 Microchip Technology, DV164121 Datasheet - Page 32

• Manufacturer Part Number: DV164121
• Description: KIT PICKIT 2 DEBUG EXPRESS
• Manufacturer: Microchip Technology
• Series: PICkit™ 2r
• Type: Microcontrollerr

Specifications of DV164121

• Contents: Board, PICkit™ 2 Programmer, Cable, CD
• Processor To Be Evaluated: PIC family
• Data Bus Width: 8 bit, 16 bit, 32 bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: PIC Micro® MCU
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

3.2
3.3
DS51553E-page 28
ISOLATE V
ISOLATE ICSPCLK OR PGC AND ICSPDAT OR PGD PINS
When V
that the typical V
If the V
The application circuit is typically connected to a pull up resistor/capacitor circuit, as
recommended in the device data sheet. Care must be taken so that the V
slew rate is not slowed down and exceeds the rise time in the programming
specification (typically 1 μs).
If a supervisory circuit or a push button is interfaced to the MCLR pin, it is
recommended that they be isolated from the V
diode or limiting resistor as shown in Figure 3-1. For more information about using
supervisory circuits with ICSP, see Application Note AN820 “System Supervisors in
ICSP™ Architectures” (DS00820).
If the V
The application circuit that connects to the I/O pin may not be able to handle the +12V
voltage. It is recommended to use a Schottky-type diode or limiting resistor as shown
in Figure 3-1 to isolate the circuitry.
The ICSPCLK or PGC and ICSPDAT or PGD pins need to be isolated from the
application circuit to prevent the programming signals from being affected by the
application circuitry. ICSPCLK or PGC is a unidirection synchronous serial
programming clock line from the programmer to the target. ICSPDAT or PGD is a
bidirectional synchronous serial programming data line.
If the design permits, dedicate these pins for ICSP. However, if the application circuit
requires that these pins be used in the application circuit, design the circuitry in a
manner that does not alter the signal level and slew rates. Isolation circuitry will vary
according to the application. Figure 3-1 shows one possibility by using series resistors
to isolate the ICSP signals from the application circuit.
PP
/MCLR/PORT PIN
PP
PP
PP
voltage is applied, the application circuit needs to take into consideration
pin is used as a MCLR pin
pin is used as an I/O port pin
PP
voltage is +12V. This may be an issue in the following situations:
PP
voltage by using a Schottky-type
© 2008 Microchip Technology Inc.
PP
voltage