The MPLAB ICD 3 is a mature product and no new device support will be added to it as of June 1, 2019. For new designs, consider using the MPLAB ICD 4 (DV164045)
MPLAB® ICD 3 In-Circuit Debugger System is Microchip's most cost effective high-speed hardware debugger/programmer for Microchip Flash Digital Signal Controller (DSC) and microcontroller (MCU) devices. It debugs and programs PIC® Flash microcontrollers and dsPIC® DSCs with the powerful, yet easy-to-use graphical user interface of MPLAB Integrated Development Environment (IDE).
The MPLAB ICD 3 In-Circuit Debugger probe is connected to the design engineer's PC using a high-speed USB 2.0 interface and is connected to the target with a connector compatible with the MPLAB ICD 2 or MPLAB REAL ICE systems (RJ-11). MPLAB ICD 3 supports all Emulation headers.
MPLAB ICD 3 has improved speed as compared with MPLAB ICD 2.
Get started with the ICD 3 here.
MPLAB ICD 3 In-Circuit Debugger/Programmer supports most Flash PIC MCUs and dsPIC DSCs. For the current list of supported parts, review the latest release notes located in the MPLAB IDE and attached below. The firmware is continually being updated to add support for new devices. As new device firmware is released, it can be downloaded with the latest version of MPLAB X IDE, free of charge.
Notes about Headers
Some 8-, 14- and 18-pin devices use small header boards with a special MCU for debugging. This special MCU has extra pins for MPLAB ICD 3 communication and therefore allows the use of all pins on the part for the application. The header board is not used or needed for programming. However, when debugging these devices the header must be used. See the "Header Specification" document below or see a list of current devices that use headers here.