Info:
The on-board level shifters will draw a small amount of current even when they are not in use. A
maximum of 10 µA can be drawn from the target power net, and an additional 2 µA can be drawn from
each I/O pin connected to a level shifter for a total of 20 µA. Disconnect the on-board debugger and level
shifters as described in Section
3.5 Disconnecting the On-Board Debugger
connected to a level shifter in tri-state to prevent leakage.
3.5
Disconnecting the On-Board Debugger
The block diagram below shows all connections between the debugger and the PIC18F47K42 microcontroller. The
rounded boxes represent connections to the board edge on PIC18F47K42 Curiosity Nano. The signal names shown
in
are printed in silkscreen on the bottom side of the board.
Figure 3-6. On-Board Debugger Connections to the PIC18F47K42
DEBUGGER
TARGET
Level-Shift
PA04/PA06
PA07
PA08
PA16
PA00
PA01
USB
DIR x 5
VCC_P3V3
VBUS
VCC_LEVEL
VCC_T
ARGET
DBG0
DBG1
DBG2
DBG3
CDC TX
CDC RX
CDC RX
CDC TX
DBG3
DBG2
DBG1
DBG0
GPIO straps
LDO
VOFF
LDO
VBUS
VTG
VCC_EDGE
Power Supply strap
Target Power strap
By cutting the
GPIO straps
with a sharp tool, as shown in
, all I/Os connected between the debugger and
the PIC18F47K42 are completely disconnected. To completely disconnect the target regulator and level shifter power
from the target, cut the
Power Supply strap
(J100) as shown in
.
Info:
Cutting the connections to the debugger will disable programming, debugging, data streaming, and
the target power supply. The signals will also be disconnected from the board edge next to the on-board
debugger section.
Tip:
Solder in 0Ω resistors across the footprints or short-circuit them with tin solder to reconnect any cut
signals.
PIC18F47K42 Curiosity Nano
Curiosity Nano
©
2019 Microchip Technology Inc.
User Guide
DS50002899B-page 13