Abstract: Propagation delay times of an input signal from an input terminal to respective gates are equalized and accelerated with a power MOS transistor that includes a plurality of transistor blocks. The transistor blocks are formed by sources being connected to each other by a first electric conductive layer (8.sub.2, 8.sub.4, 8.sub.6 and 10), drains being connected to each other by a second electric conductive layer (8.sub.1, 8.sub.3, 8.sub.5 and 9), and gates (6) consisting of a continuous semiconductor layer. The transistor has a third electric conductive layer (11) being connected to a gate terminal Gin and laminated on the gates. The third electric conductive layer laminated on the gates functions to equalize and accelerate propagation delay times of an input signal from an input terminal to the respective gates.
Abstract: An overcurrent detector circuit (21) for a power MOSFET (22) is described. The overcurrent detector circuit (21) generates a bias voltage corresponding to the drain to source voltage of the power MOSFET (22). The drain to source voltage correlates directly to the current being conducted by the power MOSFET (22). An overcurrent condition occurs when the power MOSFET (22) exceeds a predetermined current. The bias voltage is applied to a transistor (24) for generating a current. A current source (29) couples to the transistor (24). The current provided by the transistor equals the reference current of the current source (29) when the power MOSFET conducts the predetermined current. The overcurrent detector circuit (21) generates a signal indicating a overcurrent condition does not exist when the reference current is greater the current provided by the transistor.
Type:
Grant
Filed:
October 3, 1995
Date of Patent:
October 7, 1997
Assignee:
Motorola, Inc.
Inventors:
Thomas D. Petty, Troy L. Stockstad, Warren J. Schultz
Abstract: An object of the present invention is to contribute to increase of storage capacity of a memory. A nonvolatile memory having a cell applying to multi-bit data by multi-layered floating gate architecture. The memory has a storage cell transistor which comprises a semiconductor substrate 1, source 2, drain 3 and control gate 5. The storage cell transistor, furthermore comprises a plurality of floating gates 4B.sub.1 -4B.sub.n which are arranged in order between a channel and the control gate. Two or more bits data can be saved per one storage cell. According to this architecture, an integration factor per one storage cell leaps upward since a necessary number of floating gates are stacked to overlie each other, the particular number corresponding to the number of bits to be stored therein.
Abstract: A switchable current source (41) for a Digital to Analog Converter (DAC) to reduce noise glitches when a change in total current provided by the DAC occurs. The switchable current source (41) is one of many required by a DAC to convert a digital signal to an analog signal. Each current source of the DAC receives an input voltage that enables or disables the current source from providing or not providing a current. A sampled input voltage is alternately provided to the switchable current source (41) by a first flip flop (42) or a second flip flop (43). One flip flop samples the input voltage while the other provides a previous sampled input voltage for enabling and disabling the switchable current source (41). Switches (46,47) couple an output voltage of the first or second flip flops (42,43) a predetermined time after the output voltage changes to a transistor (51) coupled to a current source (53).