Samsung I9220 AP (PDA Part) is based on the S5PV310 (Exynos 4210) Processor (Cortex-A9 Dual-Core). JTAG pads are very small; professional experience in soldering is required to connect wires to the JTAG interface.
Note, one simple way to connect over JTAG – connect USB cable to PC and insert battery. In this case phone is automatically powered on.

To resurrect Samsung I9220 AP:

Solder JTAG cable to Samsung I9220 AP JTAG pads;
Connect USB cable to phone and PC;
Insert battery;
Make sure Samsung I9220 AP is selected in the list of models;
Make sure a fixed TCK frequency is selected;
Click Resurrect button;
Wait till software signals a successful operation completion;
Disconnect USB cable, de-solder JTAG wires;

Now phone is in bootable condition, that is, even if it does not start up normally, you can flash it using original Samsung downloader software to restore it to the working state.

To enter download mode:

Disconnect PC cable;
Insert battery;
Hold both ‘Volume Down’ and ‘Home’ keys and press Power-On