ESD protection network utilizing precharge bus lines
First Claim
1. An electrostatic discharge protection circuit comprising:
- one or more electrostatic bus lines to direct electrostatic discharge around internal circuitry;
a plurality of signal bonding pads to receive external voltage signals, each signal bonding pad is coupled to an associated electrostatic bus line via an unidirectional conducting device; and
a charge pump for each electrostatic bus line to precharge its associated electrostatic bus line to an associated predetermined voltage level, wherein pre-charging each electrostatic bus line to its predetermined voltage level reduces transient currents on the signal bonding pads associated with capacitive charging of the electrostatic bus lines when the external voltage signal levels are beyond normal supply voltage ranges.
3 Assignments
0 Petitions
Accused Products
Abstract
An electrostatic discharge protection circuit for an integrated circuit that reduces unwanted transient currents during normal operations. In one embodiment, the electrostatic discharge protection circuit includes one or more electrostatic bus lines, a plurality of signal bonding pads and charge pumps. The one or more electrostatic bus lines are used to direct electrostatic discharge around internal circuitry. The plurality of signal bonding pads are used to receive external voltage signals. Each signal bonding pad is coupled to an associated electrostatic bus line via an unidirectional conducting device. A charge pump is used on each electrostatic bus line to precharge its associated electrostatic bus line to an associated predetermined voltage level. The precharging of each electrostatic bus line to its predetermined voltage level reduces transient currents through the unidirectional conducting devices when external voltage signals having voltage levels beyond normal supply voltage ranges are applied to the signal bonding pads.
34 Citations
57 Claims
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1. An electrostatic discharge protection circuit comprising:
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one or more electrostatic bus lines to direct electrostatic discharge around internal circuitry;
a plurality of signal bonding pads to receive external voltage signals, each signal bonding pad is coupled to an associated electrostatic bus line via an unidirectional conducting device; and
a charge pump for each electrostatic bus line to precharge its associated electrostatic bus line to an associated predetermined voltage level, wherein pre-charging each electrostatic bus line to its predetermined voltage level reduces transient currents on the signal bonding pads associated with capacitive charging of the electrostatic bus lines when the external voltage signal levels are beyond normal supply voltage ranges. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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14. An integrated circuit comprising:
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functional circuitry;
a first electrostatic discharge (ESD) bus line to direct electrostatic discharge pulses away from the functional circuitry;
a first charge pump coupled to charge the first ESD bus line to a predetermined first voltage;
a second ESD bus line to further direct electrostatic discharge pulses away from the functional circuitry;
a second charge pump coupled to charge the second ESD bus line to a predetermined second voltage;
a first unidirectional conducting device coupled between a first signal connection and the first ESD bus line;
a second unidirectional conducting device coupled between a second signal connection and the second ESD bus line; and
wherein the first and second ESD bus lines are charged to their respective first and second voltage levels to reduce transient currents through the first and second unidirectional conducting devices when voltages applied to the first and second signal connections are outside the normal range of power supply operating voltages for the integrated circuit. - View Dependent Claims (15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25)
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26. An ESD protected integrated circuit comprising:
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a positive ESD bus line to route positive electrostatic discharge pulses around functional circuitry;
first and second signal bonding pads to receive external voltage signals;
a first unidirectional conducting device coupled between the first signal bonding pad and the positive ESD bus line;
a second bus line coupled to selectively receive current from the positive ESD bus line;
a second unidirectional conducting device coupled between the second signal bonding pad and the second bus line; and
a positive rail charge pump coupled to charge the positive ESD bus line to a predefined voltage level, wherein the predefined voltage level is higher than anticipated voltage signal levels that will be applied to the first signal bonding pad to reduce parasitic currents through the first unidirectional conducting device during normal operations of the integrated circuit where voltage signals higher than a normal power supply operating voltage, but less than the predefined voltage, are applied to the first signal bonding pad. - View Dependent Claims (27, 28, 29, 30, 31, 32, 33, 34, 35)
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36. An ESD protected integrated circuit comprising:
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a negative ESD bus line to route negative electrostatic discharge pulses around functional circuitry;
first and second signal bonding pads to receive external voltage signals;
a first unidirectional conducting device coupled between the first signal bonding pad and the negative ESD bus line;
a second bus line coupled to selectively receive current from the negative ESD bus line;
a second unidirectional conducting device coupled between the second signal bonding pad and the second bus line; and
a negative rail charge pump coupled to charge the negative ESD bus line to a predefined voltage level, wherein the predefined voltage level is lower than anticipated voltage signal levels that will be applied to the first signal bonding pad to reduce parasitic currents through the first unidirectional conducting devices during normal operations of the integrated circuit where voltage signals lower than a normal power supply operating voltage, but more than the predefined voltage, are applied to the first signal bonding pad. - View Dependent Claims (37, 38, 39, 40, 41, 42, 43, 44, 45)
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46. A method of operating an integrated circuit that requires signal voltages outside the normal range of operational power supply voltages, the integrated circuit including an electrostatic discharge circuit having one or more electrostatic discharge bus lines, the method comprising:
pre-charging each of the electrostatic discharge bus lines to a respective predetermined voltage level, wherein each predetermined voltage level is a voltage level beyond the signal voltage level expected to be applied to the integrated circuit. - View Dependent Claims (47, 48, 49)
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50. A method of operating an integrated circuit having electrostatic discharge protection comprising:
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coupling a positive ESD bus line to the integrated circuit to direct positive electrostatic pulses away from functional circuitry of the integrate circuit;
pre-charging the positive ESD bus line to a predetermined positive voltage level, wherein the predetermined positive voltage level is above a voltage level of expected signals to be applied to the integrated circuit;
coupling a negative ESD bus line to the integrated circuit to direct negative electrostatic pulses away from the functional circuitry of the integrated circuit; and
pre-charging the negative ESD bus line to a predetermined negative voltage level, wherein the predetermined negative voltage level is below the voltage level of expected signals to be applied to the integrated circuit. - View Dependent Claims (51, 52, 53, 54, 55, 56, 57)
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Specification