US 12,438,361 B2
Low-leakage electrostatic discharge clamp circuit
Akram A Salman, Cedar Park, TX (US)
Assigned to Apple Inc., Cupertino, CA (US)
Filed by Apple Inc., Cupertino, CA (US)
Filed on Sep. 22, 2023, as Appl. No. 18/473,161.
Prior Publication US 2025/0105622 A1, Mar. 27, 2025
Int. Cl. H02H 9/04 (2006.01)
CPC H02H 9/045 (2013.01) 20 Claims
OG exemplary drawing
 
1. An electrostatic discharge clamp circuit comprising:
a switching circuit comprising:
a first switch, wherein a drain of the first switch is coupled to a power supply rail; and
a second switch, wherein a drain of the second switch is coupled to a source of the first switch, and wherein a source of the second switch is coupled to a ground terminal;
a trigger circuit comprising a resistor, a capacitor, and an inverter, wherein the resistor is directly electrically coupled to the ground terminal, the capacitor is directly electrically coupled to the resistor via a node and directly electrically coupled to the power supply rail, an input of the inverter is directly electrically coupled to the resistor and the capacitor via the node, and an output of the inverter is directly electrically coupled to a gate of the first switch; and
a third switch, wherein a drain of the third switch is coupled to a gate of the second switch, a gate and a source of the third switch are coupled to the ground terminal, and the third switch is not coupled to the resistor, the capacitor, and the input of the inverter via the node.