The discrete solution is simple but comes with its downsides. It is bulky as the TVS needs to be large to absorb the worst-case energy pulse. For automotive designs, this is the load dump pulse with a peak surge voltage around 100V decaying exponentially to 12V over hundreds of ms. The passive components have wide tolerances, leading to overdesign. For example, an SMBJ28A TVS selected to protect a 12V automotive system, triggers at 33V for low currents but clamps high currents at 45V. Therefore, 12V electronics have to be 45V capable to survive a power supply surge. Similarly, fuses have wide tolerances and are slow in responding to load current surges. They will also blow open during a sustained or DC fault, requiring replacement. These wide tolerances lead to overdesign, increasing costs. The reverse protection diode drops voltage and dissipates power, requiring heat sinking. To summarize, the discrete solution is bulky, has wide tolerances, and requires fuse replacement after a sustained fault. A better solution is needed, one that enables a compact form factor while minimizing overdesign and repair costs.