Microchip Technology MCP402XEV User Manual
MCP401X/2X EVALUATION
BOARD USER’S GUIDE
© 2005 Microchip Technology Inc.
DS51546B-page 27
Appendix D. Potential Programming Issue of the MCP402XEV
D.1
INTRODUCTION
When programming the MCP402XEV with a Microchip programmer (such as the BPMF
or MPLAB
or MPLAB
®
ICD 2), the PIC10F206 may not program correctly due to the load on the
ICSPDAT pin. This issue relates to PCBs marked 104-00066 and 104-00066R2.
Due to the current path to ground that is present with the D1 and R1 components
through capacitor C2, the programming voltage on the ICSPDAT signal may not meet
the voltage requirements of the PIC10F206 GP1 pin.
through capacitor C2, the programming voltage on the ICSPDAT signal may not meet
the voltage requirements of the PIC10F206 GP1 pin.
To address this when programming the board, lift up one of the terminals of capacitor
C2 (see Figure D-1). This will stop the ICSPDAT signal voltage from being loaded down
while capacitor C2 is charging. The schematic is shown in Figure D-2.
C2 (see Figure D-1). This will stop the ICSPDAT signal voltage from being loaded down
while capacitor C2 is charging. The schematic is shown in Figure D-2.
After programming, capacitor C2 must be reconnected to the circuit. This is because
this circuit generates the high voltage for the high voltage commands.
this circuit generates the high voltage for the high voltage commands.
FIGURE D-1:
MCP402XEV R2 PCB Layout – ECN #1.
lift this end
This capacitor connection needs
to be opened for programming.
to be opened for programming.
After programming has been
completed, this capacitor needs
to be reconnected in the circuit.
completed, this capacitor needs
to be reconnected in the circuit.