Microchip Technology MPLAB ICD 4 User Manual

Operation
 2017 Microchip Technology Inc. DS50002596A-page 21
2.3.3 Target Power
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
PP/MCLR), 5 (PGC), and 4 (PGD). Pins 2 (VDD) and 3 (VSS) are
shown on Figure 2-4 for completeness.
When providing power to the target device, ensure that the target is not exposed to
voltages higher than the device V
DD rating.
Absolute maximum ratings for the device V
DD must not be exceeded. Exposure to the
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 EXTERNALLY POWERED THROUGH TARGET
The recommended method for powering the target device is an external power supply
connected directly to the target board. In this configuration, target V
DD is sensed by the
debugger to allow level translation for the target low-voltage operation. If the debugger
does not sense voltage on its V
DD line (pin 2 of the interface connector), it will not
operate.
2.3.3.2 EXTERNALLY POWERED THROUGH DEBUGGER
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
DD and AVSS lines, but if they are present on the target
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
DD/AVDD and VSS/AVSS lines be connected to
the appropriate levels. Also, devices with a V
CAP line (PIC18FXXJ MCUs, for example)
should be connected to the appropriate capacitor or level.
Note: 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.

Microchip Technology MPLAB ICD 4 Specifications

General

Brand	Microchip Technology
Model	MPLAB ICD 4
Category	Computer Accessories
Language	English