US 12,316,106 B2
Electrostatic protection circuit for controlling a secondary monitoring unit by a control circuit
Ling Zhu, Hefei (CN); and Kai Tian, Hefei (CN)
Assigned to CHANGXIN MEMORY TECHNOLOGIES, INC., Hefei (CN)
Filed by CHANGXIN MEMORY TECHNOLOGIES, INC., Hefei (CN)
Filed on Jul. 2, 2022, as Appl. No. 17/810,599.
Application 17/810,599 is a continuation of application No. PCT/CN2021/138502, filed on Dec. 15, 2021.
Claims priority of application No. 202111300465.5 (CN), filed on Nov. 4, 2021.
Prior Publication US 2023/0136979 A1, May 4, 2023
Int. Cl. H02H 9/04 (2006.01); H03K 17/30 (2006.01)
CPC H02H 9/046 (2013.01) [H03K 17/302 (2013.01)] 13 Claims
OG exemplary drawing
 
1. An electrostatic protection circuit for a chip comprising a power supply pad and a ground pad, the electrostatic protection circuit comprising:
a monitoring assembly, configured to generate a trigger signal when an electrostatic pulse is present on the power supply pad;
a discharge transistor connected between the power pad and the ground pad, and configured to be turned on under control of the trigger signal to discharge electrostatic charges to the ground pad; and
a control circuit connected to the monitoring assembly, and configured to control a duration of the trigger signal generated by the monitoring assembly;
wherein the monitoring assembly comprises:
a primary monitoring unit and at least one secondary monitoring unit,
wherein
the primary monitoring unit is connected between the power supply pad and the ground pad;
the primary monitoring unit and the secondary monitoring unit are both connected to a control terminal of the discharge transistor, and output signals of the primary monitoring unit and the secondary monitoring unit are together applied to the control terminal; and
the secondary monitoring unit is connected to the control circuit;
wherein the control circuit comprises at least one first control unit and at least one second control unit, a number of the at least one first control unit being identical to a number of the at least one second control unit, and being identical to a number of the at least one secondary monitoring unit,
wherein the first control unit is connected between the secondary monitoring unit and the power supply pad, and the first control unit is configured to control an operation state of the secondary monitoring unit by a power supply voltage supplied from the power supply pad; and
the second control unit is connected between the secondary monitoring unit and the ground pad, and the second control unit is configured to control the operation state of the secondary monitoring unit by a ground voltage supplied from the ground pad.