ESD protection circuit cell
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorBo-Ting Chen
Life of this patent
Estimating the term…
Abstract
A protection cell for a cell library. The protection cell defines a protection circuit for an IC having a driving device with a first supply voltage Vdd1 and an output, and a driven device having an input and a second supply voltage Vdd2. The protection circuit includes a first device from the group consisting of a P-diode and a gate-Vdd PMOS. The first device is coupled between a first power bus connected to Vdd2 and the input of the driven device. The input of the driven device is coupled by way of a resistor to the output of the driving device. A second device corresponding to the first device is provided, from the group consisting of an N-diode and a grounded gate NMOS. The second device is coupled between the input of the driven device and a ground bus.
Claims20
A persistent, computer readable storage medium encoded with a cell library for an electronic design automation (EDA) tool, the cell library having a plurality of cell designs for implementing respective functions, wherein the cell library comprises:
- a first protection cell defining a protection circuit, the protection circuit comprising:
- a first device coupled between a first power bus and an input of a driven device, the input of the driven device coupled to an output of a driving device;
- and
- a second device, wherein the first and second devices are arranged symmetrically about horizontal and vertical centerlines of the protection circuit, the second device coupled between the input of the driven device and a first ground bus.
A persistent, computer readable storage medium encoded with a cell library for an electronic design automation (EDA) tool, the cell library having a plurality of cell designs for implementing respective functions, wherein the library comprises:
- a first protection cell defining a protection circuit for an integrated circuit having a driving device with a first supply voltage Vdd1 and an output, and a driven device having an input and a second supply voltage Vdd2, the protection circuit comprising:
- a first device coupled between a first power bus coupled to Vdd2 and the input of the driven device, the input of the driven device coupled by way of a resistor to the output of the driving device;
- and
- a second device coupled between the input of the driven device and a first ground bus;
- and
- a receiving cell for laying out at least the input of the driven device,
- wherein the protection cell has a cell height that is the same as a cell height of the receiving cell.
A method of laying out an integrated circuit (IC), comprising:
- selecting a first protection cell from a cell library, the first protection cell defining a protection circuit for an IC having a driving device with a first supply voltage Vdd1 and an output, and a driven device having an input and a second supply voltage Vdd2, the protection circuit comprising:
- a first device coupled between a first power bus connected to Vdd2 and the input of the driven device, the input of the driven device coupled by way of a resistor to the output of the driving device;
- and
- a second device coupled between the input of the driven device and a ground bus;
- and
- selecting a receiving cell from the cell library for laying out at least the input of the driven device, wherein the first protection cell has a cell height that is the same as a cell height of the receiving cell;
- and
- using an electronic design automation (EDA) tool to lay out the IC so as to include the first protection cell and the receiving cell.
Dependencies are inferred from the claim text.