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`1. An electrostatic protection circuit for a chip comprising a ground pad andat least one
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`probe pad, the electrostatic protection circuit comprising: a monitoring unit, a discharge unit
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`and a controllable voltage dividing unit,
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`wherein the monitoring unit
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`is connected to the discharge unit,
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`the controllable
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`voltage dividing unit and the at least one probe pad, and the monitoring unit is configured to
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`generate a first trigger signal in responseto that an electrostatic pulse is present on any probe
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`pad;
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`the discharge unit is connected between the ground pad andthe at least one probe pad,
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`and configured to form, under control of the first
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`trigger signal, at least one path for
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`discharging electrostatic charges to the ground pad; and
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`the controllable voltage dividing unit
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`is connected to the discharge unit and
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`configured to share a part of voltage of the first trigger signal for the discharge unit.
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`2. The circuit of claim 1, wherein the discharge unit comprises at least one transistor; the
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`controllable voltage dividing unit comprises: a first voltage dividing element havingafirst
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`end and a second end, and a second voltage dividing element having a first end and a second
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`end,
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`the first voltage dividing element and the second voltage dividing element being
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`configured to share the part of voltage of the first trigger signal for the at least one transistor,
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`wherein the first ends of the first voltage dividing element and the second voltage
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`dividing element are correspondingly connected to a gate of a respective one of the at least
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`one transistor,
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`the second end of the first voltage dividing element is connected to the
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`monitoring unit, and the second end of the second voltage dividing element is connected to a
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`ground terminal.
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`3. The circuit of claim 2, wherein the at least one transistor comprises a second transistor and
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`a fourth transistor; the first voltage dividing element comprises a first resistor and a third
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`resistor; and the second voltage dividing element comprises a second resistor and a fourth
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`resistor,
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`wherein a first end of the first resistor and a first end of the second resistor are both
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`connected to a gate of the secondtransistor, and a first end of the third resistor and a first end
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`of the fourth resistor are both connected to a gate of the fourth transistor; and
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`a second end ofthe first resistor and a second end ofthe third resistor are respectively
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`connected to the monitoring unit, and a second end of the second resistor and a second end of
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`the fourth resistor are both connected to the ground terminal.
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`4. The circuit of claim 3, wherein the discharge unit further comprises a first transistor and a
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`third transistor,
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`a drain of the first transistor and a drain of the third transistor being respectively
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`connected to a respective one of the at least one probe pad;
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`a gate of the first transistor and a gate of the third transistor being respectively
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`connected to the monitoring unit; and
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`a source of the first transistor being connected to a drain of the second transistor, and
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`a source of the third transistor being connectedto a drain of the fourth transistor.
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`5. The circuit of claim 1, wherein the monitoring unit comprises: a capacitor module
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`configured to generate the first trigger signal by resistance-capacitance coupling, in response
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`to that the electrostatic pulse is present on any probe pad,
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`wherein a first end of the capacitor module is connected to the at least one probe pad,
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`a second end of the capacitor module is connected to the discharge unit, and a third end of the
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`capacitor module is connected to the controllable voltage dividing unit.
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`6. The circuit of claim 5, wherein the capacitor module comprises: a first capacitor, a second
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`capacitor, a third capacitor and a fourth capacitor,
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`wherein a first end of the first capacitor and a first end of the third capacitor are
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`respectively connected to a respective one of the at least one probe pad, the first end of the
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`first capacitor and the first end of the third capacitor serving as a first end of the capacitor
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`module;
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`a second end of the first capacitor and a second end of the second capacitor are both
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`connected to a gate of a first transistor of the discharge unit, a second end of the third
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`capacitor and a second end of the fourth capacitor are both connected to a gate of a third
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`transistor of the discharge unit, wherein a connection terminal connecting the first capacitor
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`and the second capacitor and a connection terminal connecting the third capacitor and the
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`fourth capacitor serve as the second end of the capacitor module; and
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`a first end of the second capacitor and a first end of the fourth capacitor are
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`respectively connected to the controllable voltage dividing unit, wherein the first end of the
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`second capacitor and the first end of the fourth capacitor serves as the third end of the
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`capacitor module.
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`7. The circuit of claim 4, wherein the at least one probe pad comprises a first probe pad and a
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`second probe pad,
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`both the drain of the first transistor and a first end of a first capacitor of a capacitor
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`module of the monitoring unit are connected to the first probe pad; and
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`both the drain of the third transistor and a first end of a third capacitor of the capacitor
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`module are connected to the second probe pad.
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`8. The circuit of claim 4, wherein a first end of a second capacitor of a capacitor module of
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`the monitoring unit is connected to the second end of the first resistor; and a first end of a
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`fourth capacitor of the capacitor module is connected to the second endofthe third resistor.
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`9. The circuit of claim 1, wherein the chip further comprises a power supply pad,
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`the monitoring unit
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`is further connected to the power supply pad, and further
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`configured to generate a second trigger signal in response to that an electrostatic pulse is
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`present on the power supply pad; and
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`the discharge unit is further connected between the power supply pad and the ground
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`pad, and further configured to be turned on undercontrol of the secondtrigger signal, so as to
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`discharge the electrostatic charges to the ground pad.
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`10. The circuit of claim 9, wherein the monitoring unit further comprisesa fifth capacitor and
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`a fifth resistor,
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`wherein a first end of the fifth capacitor is connected to the power supply pad, a
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`second end of the fifth capacitor is connected to a first end of the fifth resistor, and a second
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`end ofthe fifth resistor is connected to the ground pad,
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`wherein the fifth capacitor is configured to generate the second trigger signal by
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`resistance-capacitance coupling, in response to that the electrostatic pulse is present on the
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`powersupply pad.
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`11. The circuit of claim 10, wherein the discharge unit further comprisesa fifth transistor,
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`a drain of the fifth transistor being connected to the power supply pad, a source of the
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`fifth transistor being connected to the ground pad, and the second endofthe fifth capacitor
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`and the first end of the fifth resistor being also both connected to a gate of the fifth transistor,
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`wherein the fifth transistor is configured to be turned on under control of the second
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`trigger signal, so as to discharge the electrostatic charges to the ground pad.
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`12. The circuit of claim 4, wherein the first transistor,
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`the second transistor,
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`the third
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`transistor and the fourth transistor are all Negative-channel Metal-Oxide-Semiconductor
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`(NMOS)transistors.
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`13. A chip comprising a ground pad and at least one probe pad, wherein the chip further
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`comprises an electrostatic protection circuit comprising: a monitoring unit, a discharge unit
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`and a controllable voltage dividing unit,
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`wherein the monitoring unit
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`is connected to the discharge unit,
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`the controllable
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`voltage dividing unit and the at least one probe pad, and the monitoring unit is configured to
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`generate a first trigger signal in responseto that an electrostatic pulse is present on any probe
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`pad;
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`the discharge unit is connected between the ground pad andthe at least one probe pad,
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`and configured to form, under control of the first
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`trigger signal, at least one path for
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`discharging electrostatic charges to the ground pad; and
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`the controllable voltage dividing unit is connected to the discharge unit and configured to
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`share a part of voltage of the first trigger signal for the discharge unit.
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`14. The chip of claim 13, wherein the chip comprises at least a semiconductor memory.
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`15. The chip of claim 14, wherein the semiconductor memory comprises at least a Dynamic
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`Random Access Memory (DRAM).
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