Globalfoundries U.S. Inc.

Suresh Pasupula

Devesh Dwivedi

Siva Kumar Chinthu

Venkatesh P Gopinath

Kevin A Batson

Chunsung Chiang

Anoop Delampady

A pre-driver includes first, second, third, and fourth P-channel field effect transistors (PFETs) with voltage ratings equal to a low first voltage (V). Between power rails at Vand at a higher second voltage (V), the first and third PFETs are series-connected and the second and fourth PFETs are also series-connected. The third and fourth PFETs are cross-coupled. The first and second PFETs have gates that receive a pre-driver input signal (Pin) that switches between Vand ground and an inverted pre-driver input signal (Pinb), respectively. At an output node between the first and third PFETs, the pre-driver outputs a driver input signal (Din) that switches between Vand V. A circuit includes this pre-driver (e.g., connected between a voltage level shifter and a driver or connected between a voltage level shifter and a buffer).

Compact high voltage pre-driver and circuits including the pre-driver

A disclosed circuit structure includes a voltage level shifter connected to a variable voltage generator for receiving a low supply voltage and to a programmable voltage generator for receiving a high supply voltage that is higher than the low supply voltage. The high supply voltage is programmable to one of multiple different voltage levels. The variable voltage generator tracks the voltage level of the high supply voltage and outputs the low supply voltage based thereon. The high supply voltage is tracked either directly or using the trim bit signal employed by the programmable voltage generator to program the high supply voltage. The low supply voltage is high when the high supply voltage is high to ensure operation within the safe operating area and is low when the high supply voltage drops below some threshold level to ensure operability and, optionally, improve operating speed.

Voltage level shifter with programmable high supply voltage and high supply voltage-dependent variable low supply voltage

The present disclosure relates to semiconductor structures and, more particularly, to a LDO regulator circuit and methods of manufacture. The structure includes a comparator connected to a first transistor of a low drop-out (LDO) circuit; a second transistor connected to the first transistor; and a feedback loop connected to the first transistor and an output of the LDO circuit.

Low drop-out (LDO) regulator circuit

Disclosed are a sense circuit and memory structure incorporating the sense circuit. The sense circuit is connected to voltage rails at VDD1 and VDD2, respectively, where VDD2˜½*VDD1. During a sensing operation, VDD1 provides power to develop a voltage differential between Vdata and Vref on sense nodes. A voltage comparator samples Vdata and Vref and, based on a detectable voltage differential (minVdiff), outputs a data output value. To increase the speed at which minVdiff is reached, an equalization process is performed at the initiation of the sensing operation and includes using pre-charge transistors to quickly equalize the sense nodes to VDD2. Following equalization, Vdata and Vref only need to be pulled up or down from VDD2. Thus, minVdiff is reached faster and sampling by the voltage comparator can be performed earlier in time, reducing the overall time required for performing the sensing operation and for powering the sense circuit.

Multi-rail sense circuit with pre-charge transistors and memory circuit incorporating the sense circuit

A structure includes a level shifter, first and second variable voltage generators, and a programmable voltage generator. The level shifter includes low and high supply voltage nodes and two parallel branches, including multiple transistors, connected between the nodes. The programmable voltage generator generates and applies a high supply voltage (VH) to the high supply voltage node. VH is programmable to one of multiple possible VH levels. Based on the voltage level of VH, the first variable voltage generator generates and applies a low supply voltage (VL) to the low supply voltage node and the second variable voltage generator generates and applies a gate bias voltage (VGB) to gates of some transistors. By tracking VH and adjusting VL and VGB based on thereon, the voltage level shifter operates within the SOA at high VHs, remains operable at low VHs, and maintains operating speed at mid-level VHs.

Voltage level shifter with multi-step programmable high supply voltage and high supply voltage-dependent variable low supply and gate bias voltages

Embodiments of the disclosure provide memory circuit, a sense amplifier and associated method for reading a resistive state in a memory device. The sense amplifier includes a bit cell configurable to a high or low resistance state; a sensing circuit that detects a voltage drop across the bit cell in response to an applied read current during a read operation and generates a high or low logic output at an output node; and a pulse generation circuit that increases the applied read current with an injected current pulse when a low to high transition of the resistive state of the bit cell is detected.

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Bengaluru, India

Suresh Pasupula