Semiconductor device

A semiconductor device, comprising:

• a substrate;
• a first well of a first type, disposed on the substrate;
• a first doped region of the first type, disposed in the first well, wherein the first doped region is configured as a first terminal of a first diode and is coupled to a first voltage terminal configured to receive a first supply voltage;
• a second doped region of a second type disposed in the first well, wherein the second doped region is configured as a second terminal of the first diode and is coupled to an input/output (I/O) pad;
• a second well of the second type disposed on the substrate and adjacent to the first well;
• a third doped region of the first type, disposed in the second well, wherein the third doped region is configured as a first terminal of a second diode and is coupled to a second voltage terminal configured to receive a second supply voltage;
• and
• a fourth doped region of the second type disposed in the second well, wherein the fourth doped region is configured as a second terminal of the second diode and is coupled to the second voltage terminal;
• wherein the first diode, the first voltage terminal, and a clamp circuit coupled between the first voltage terminal and the second voltage terminal are configured as a first electrostatic discharge (ESD) path between the I/O pad and the second voltage terminal, and
• wherein the second doped region, the first well, the substrate, the second well, and the third doped region are configured as a second ESD path between the I/O pad and the second voltage terminal.