Sense FET having a selectable sense current ratio and method of manufacturing the same

A sense FET comprising:

• a main cell array having a plurality of MOSFET cells connected in parallel;
• a main pad electrically connected to sources of the MOSFET cells of the main cell array;
• a sense cell array composed of a plurality of unit sense cells arranged in groups, each unit sense cell having a gate and drain connected to gates and drains respectively of the MOSFET cells of the main cell array;
• a plurality of sense pads each of which has at least one center sense pad to which a wire is to be connected and at least one auxiliary sense pad to which the wire is not connected, corresponding to each of the plurality of the groups, each source pad electrically connected to sources of the unit sense cells of the corresponding group;
• and
• at least one metal thin film fuse capable of being electrically cut for connecting the center sense pad to the auxiliary sense pad, respectively.

A sense FET comprising:

• a main cell array having a plurality of MOSFET cells connected in parallel;
• a main pad electrically connected to sources of the MOSFET cells of the main cell array;
• a plurality of sense cell arrays composed of a plurality of unit sense cells having gates and drains connected to gates and drains respectively of the MOSFET cells of the main cell array;
• a plurality of sense pads corresponding to each of the plurality of sense cell arrays, each sense pad being electrically connected to sources of the unit sense cells of the corresponding sense cell array;
• and
• a plurality of metal thin film fuses capable of being electrically cut for connecting the sense pads to each other and to the main pad.

A method of forming a sense FET comprising the steps of:

• forming a main cell array having a plurality of MOSFET cells connected in parallel and a plurality of unit sense cells, the unit sense cells arranged in a plurality of groups and having drains and gates connected to drains and gates respectively of the MOSFET cells of the main cell array;
• forming a main pad electrically connected to sources of the MOSFET cells of the main cell array and a plurality of sense pads, each sense pad being electrically connected to sources of the unit sense cells of a single group;
• and
• forming at least one fuse connecting one of the sense pads to one of the main pad and another one of the sense pads.

A method of forming a sense FET comprising:

• forming a main cell array having a plurality of MOSFET cells connected in parallel and a plurality of unit sense cells, the unit sense cells arranged in a plurality of groups and having drains and gates connected to drains and gates respectively of the MOSFET cells of the main cell array;
• forming a main pad electrically connected to sources of the MOSFET cells of the main cell array and a plurality of sense pads, each sense pad being electrically connected to sources of the unit sense cells of a single group;
• forming at least one fuse connecting one of the sense pads to one of the main pad and another one of the sense pads;
• and
• wire bonding at least one of the sense pads to a terminal of a sense FET package.