Back to results
US 7,843,259 B2Granted
Field effect transistor circuit and method of operation of field effect transistor circuit for reducing thermal runaway
AssigneeNXP B.V.
InventorJohn R. Cutter
Life of this patent
Estimating the term…
Abstract
A field transistor is divided into a number of cells (6) and includes a separate first gate line (20) connected to first transistor cells (8) and a separate second gate line (22) connected to second transistor cells (10). A drive circuit is used to drive all the cells (6) in a normal, saturated operations state but to drive only the second cells (10) in a linear operations state to reduce the number of cells used in the linear operations state.
Claims11
A field effect transistor circuit, comprising;
- a semiconductor substrate having a first major surface;
- a plurality of transistor cells arranged across the substrate, each transistor cell including a FET having an insulated gate, a source and a drain;
- wherein the transistor cells are divided into first cells and second cells, there being more first cells than second cells;
- a first gate line connected to the first cells and a separate second gate line connected to the second cells;
- and
- a means for driving the second gate line separately from the first gate line for turning on only the FETs of the second cells in a linear operation state.
3 more elements
A method of operation of a field effect transistor circuit including a semiconductor substrate defining a first major surface;
- a plurality of transistor cells arranged across the substrate, each transistor cell including a FET having an insulated gate, a source and a drain wherein the cells are divided into first cells and second cells, there being more first cells than second cells, the method including:
- driving the field effect transistor circuit in a saturated operation state by driving all of the gates of all of the FETs to switch the transistor cells on;
- and
- driving the field effect transistor circuit in a linear operation state in which the FETs of the transistor cells are not fully turned on, by driving the second cells to be in a linear operation condition but leaving the first cells turned off.
1 more element
Dependencies are inferred from the claim text.