Microchip Technology MPLAB ICD 4 User Manual page 21

2.3.3
There are two methods for externally powering the target:
• Externally Powered through Target
• Externally Powered through Debugger
In the following descriptions, only three lines are active and relevant to core debugger
operation: pins 1 (V
shown on
When providing power to the target device, ensure that the target is not exposed to
voltages higher than the device V
Absolute maximum ratings for the device V
maximum rating conditions for any length of time may affect device reliability.
Functional operation of the device at conditions above the parameters indicated in the
device data sheets specification is not recommended.
See the device data sheet for required device voltage levels and maximum ratings.
2.3.3.1
The recommended method for powering the target device is an external power supply
connected directly to the target board. In this configuration, target V
debugger to allow level translation for the target low-voltage operation. If the debugger
does not sense voltage on its V
operate.
2.3.3.2
An alternative method of powering the target device is an external power supply
connected directly to the MPLAB ICD 4. Be aware that you must also select power from
the MPLAB ICD 4 debugger via MPLAB X IDE.
Not all devices have the AV
device, all must be connected to the appropriate levels in order for the debugger to
operate. They cannot be left floating.
In general, it is recommended that all V
the appropriate levels. Also, devices with a V
should be connected to the appropriate capacitor or level.
Note:
 2017 Microchip Technology Inc.
Target Power
/MCLR), 5 (PGC), and 4 (PGD). Pins 2 (V
PP
Figure 2-4 for completeness.
DD
EXTERNALLY POWERED THROUGH TARGET
line (pin 2 of the interface connector), it will not
DD
EXTERNALLY POWERED THROUGH DEBUGGER
and AV
DD
The interconnection is very simple. Any problems experienced are often
caused by other connections or components on these critical lines that
interfere with the operation of the MPLAB ICD 4 In-Circuit Debugger
system, as discussed in the following section.
rating.
must not be exceeded. Exposure to the
DD
lines, but if they are present on the target
SS
/AV and V /AV
DD DD SS SS
line (PIC18FXXJ MCUs, for example)
CAP
Operation
) and 3 (V ) are
DD SS
is sensed by the
DD
lines be connected to
DS50002596A-page 21