Analysis and solution to overcome EOS failure induced by latchup test in a high-voltage integrated circuits

Proper layout and additional circuit solution have been proposed to solve the practical EOS failure induced by latchup test in an industry case of high-voltage integrated circuits (IC). The modified design has been implemented in 0.6-um 40-V BCD (Bipolar-CMOS-DMOS) process to successfully pass the 500-mA negative trigger current test. By eliminating overstress damages as happened in the prior work with only guard ring protection, the proposed solution can be adopted to implement high-voltage-applicable IC products which meet the requirement of industry applications with sufficient latchup immunity.