A decoder circuit for a metal-oxide-semiconductor (MOS) memory array which employs a single clock or timing signal is disclosed. Inverter buffers are utilized with a plurality of different decoder logic circuits. Discrimination of each input address is accomplished by the structurally different decoder logic circuits as opposed to the prior art technique of selecting different buffered address inputs.
An elementary decoder circuit for a monolithically integrated static random access memory is constructed by means of gallium arsenide field effect transistors and formed by a NOR-gate whose n inputs receive the n coded addressing signals a.sub.1, a.sub.2, . . . , a.sub.n of the memory, or their complements, and whose output supplied a signal which is applied to the upper transistor of a push-pull stage as well as a complementary signal, obttained via an inverter transistor, which is applied to the lower transistor of the push-pull stage. The junction point of the two transistors of the push-pull stage supplies the word line signal of the memory, and the two transistors of the push-pull stage are of the enhancement type, like the transistors of the NOR-gate, the output signal of the NOR-gate being applied to the input of the inverter transistor via a level shifting diode so that the biasing of the transistors of the push-pull stage results in an extremenly fast data transfer from the output of the NOR-gate to the word line.
A decoder circuit for a static random access memory cell and which may be integrated in monolithic form using gallium arsenide field effect transistors. The circuit comprises a first logic NOR-gate P.sub.1 having (n+1) inputs on which the n coded memory address signals or their complements are received, and also the chip-enable selection signal SB. The gate P.sub.1 is connected by a load resistor R to a supply voltage V.sub.DD1. A second NOR-gate P.sub.2 receives the same inputs as the gate P.sub.1 and has as its load a transistor T.sub.0 the gate electrode of which receives the output of the gate P.sub.1 and the drain of which is connected to a power supply voltage V.sub.DD2 which is less than V.sub.DD1. The voltage V.sub.DD2 is also the supply voltage for the memory cell, and is set at the clipping value of the gate junctions of the constituent transistors of that cell. The output V.sub.S of the decoder is produced at the drains of the transistors forming the second NOR-gate P.sub.2 which are connected to the source electrode of the load transistor T.sub.0. The inputs of the NOR-gates receive a chip-enable selection signal SB after application of the n coded memory address signals, thereby achieving reduced access time for the memory cell.
A PROM device having the improved bit address decoders composed of a plurality of AND gates, each of the AND gates comprising PNP type transistors, to each base of which is applied an address signal from the bit address inverters. Each collector of these transistors is connected to ground, and each emitter is connected to the output terminal of the bit address decoder.
A logic circuit, comprising a plurality of driver MOSFETs and one load MOSFET, produces an output signal responsive to input signals. The driver MOSFETs are each controlled by an input signal and the load MOSFET is controlled by one of input signals to conduct at opposite times to the driver MOSFET controlled by the same input signal. Therefore, a logic circuit with low power consumption and a small area is provided.
A metal-oxide-semiconductor (MOS) static decoding circuit for selecting an addressed line in a high density memory array, or the like, is disclosed. The circuit may be laid-out along array lines where the lines have a pitch of approximately 12.25 microns. Three levels of decoding are employed. The highest level permits the pulling-up of a common node in the second level decoder. The third level of decoding selects one of a plurality of array lines coupled to this node. Zero threshold voltage MOS devices are employed for coupling the first and third decoders to the second decoder.
