Derivative works — US Patent 8148962

Defensive Disclosure: Derivative Art for Transient Load Voltage Regulators

Publication Date: May 13, 2026
Reference Patent: US 8,148,962 ("the '962 patent")
Author: Senior Patent Strategist and Research Engineer

This document discloses novel and non-obvious variations, extensions, and applications of the transient load voltage regulator technology described in US patent 8,148,962. The purpose of this disclosure is to place these concepts in the public domain, thereby establishing prior art against future patent applications claiming these or similar inventions.

Derivatives Based on Claim 1: Core Regulator Circuit

1. Material & Component Substitution

Derivative 1.1: Graphene-Based Pass Device
- Enabling Description: The NMOS or PMOS pass device (350) is replaced with a Graphene Field-Effect Transistor (GFET). The high carrier mobility of graphene allows for significantly faster switching times and lower on-resistance (Rds_on) compared to silicon, enabling a more rapid response to transient load changes. The gate of the GFET is coupled to the second current path (376), and its control mechanism remains analogous to the MOSFET described in the '962 patent. The GFET is fabricated on a silicon carbide (SiC) substrate to manage thermal dissipation. The faster response reduces the required capacitance of any associated stability capacitor (586), allowing for a smaller circuit footprint.
- Mermaid.js Diagram:
```
graph TD
    A[Second Current Path] -->|Control Voltage| B(GFET Gate);
    C(Power Supply Input) --> D{GFET Drain/Source};
    D --> E(Output to Load);
    B -.-> D;
```
Derivative 1.2: Organic Semiconductor Feedback Circuit
- Enabling Description: The feedback transistor (332) and its associated differential amplifier (333) are implemented using organic thin-film transistors (OTFTs) based on a pentacene active layer. This substitution allows the regulator to be integrated onto flexible or transparent substrates, such as polyethylene naphthalate (PEN). While the response time may be slower than silicon-based equivalents, the application is suited for low-power, flexible electronics where mechanical resilience is paramount. The feedback circuit maintains a substantially constant gate voltage for the organic feedback transistor, providing a stable reference for the second current supply circuit.
- Mermaid.js Diagram:
```
classDiagram
    class OrganicFeedbackCircuit {
        +OTFT_FeedbackTransistor
        +OTFT_DifferentialAmplifier
        +maintainConstantGateVoltage()
    }
    class SecondCurrentSupply {
        -referenceVoltage
        +generateVariableCurrent()
    }
    OrganicFeedbackCircuit --|> SecondCurrentSupply : provides_reference
```

2. Operational Parameter Expansion

Derivative 1.3: Cryogenic High-Frequency Regulator
- Enabling Description: The entire voltage regulator circuit is designed to operate in a cryogenic environment (below 77 Kelvin) for applications in quantum computing or high-sensitivity scientific instrumentation. All transistors (pass device, feedback, current sources) are fabricated using silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs) which exhibit improved performance at low temperatures. The regulator is designed to stabilize voltage for loads operating in the high GHz frequency range (e.g., 10-100 GHz). At these temperatures, thermal noise is significantly reduced, allowing for a much more precise comparison between the output voltage and the reference voltage, resulting in an output voltage with microvolt-level stability.
- Mermaid.js Diagram:
```
sequenceDiagram
    participant Load @ 50 GHz;
    participant Regulator @ 77K;
    Load->>Regulator: Voltage droop event (picoseconds);
    Regulator->>Regulator: SiGe HBTs react;
    Regulator->>Load: Compensated current supplied;
```
Derivative 1.4: High-Voltage Industrial Scale Regulator
- Enabling Description: The circuit is scaled to regulate high-voltage DC buses (e.g., 400V to 1000V) in industrial motor drives or electric vehicle power distribution units. The pass device (350) is an array of parallel Gallium Nitride (GaN) High-Electron-Mobility Transistors (HEMTs). The feedback circuit is galvanically isolated from the high-voltage output using a high-speed digital opto-isolator. The output voltage is sensed via a precision resistive divider network rated for high voltages. The second current supply circuit (340) adjusts the current to the GaN HEMT gates, controlling the high-power output in response to transient loads, such as motor startup or regenerative braking.
- Mermaid.js Diagram:
```
graph LR
    subgraph Low-Voltage Control
        A[Feedback Circuit] --> B{Second Current Supply};
    end
    subgraph High-Voltage Power
        D(HV DC Input) --> E[GaN HEMT Array];
        E --> F(HV DC Output);
        F --> G((Resistive Divider));
    end
    G -- V_sense --> C{Opto-isolator};
    B -- I_control --> C;
    C -- Gate Drive --> E;
```

3. Cross-Domain Application

Derivative 1.5: Aerospace - Avionics Power Bus Stabilization
- Enabling Description: The regulator is used to stabilize the 28V DC power bus in an aircraft's fly-by-wire flight control system. The load consists of multiple redundant flight control computers and electro-hydraulic actuators that are selectively powered. The circuit is implemented in a radiation-hardened silicon-on-insulator (SOI) process to mitigate single-event upsets (SEUs) from cosmic radiation. The feedback loop is tuned for the specific transient signature of actuator engagement, ensuring that voltage drops do not cause a reboot or fault in the flight control computers.
- Mermaid.js Diagram:
```
stateDiagram-v2
    [*] --> Stable_28V
    Stable_28V --> Transient_Load: Actuator Engages
    Transient_Load --> Stable_28V: Regulator Increases I_load
    Stable_28V --> Low_Power: Non-critical systems off
    Low_Power --> Stable_28V: Systems reactivated
```
Derivative 1.6: AgTech - Autonomous Tractor Sensor Array
- Enabling Description: The regulator provides a stable 5V supply to a sensor array on an autonomous tractor. The load varies significantly as different sensors (LIDAR, multispectral cameras, GPS modules) are powered on and off. The regulator is housed in a hermetically sealed package to protect against dust, moisture, and vibration. The second current source (340) is designed with a wide dynamic range to handle the large current swing between the LIDAR scanner's peak power draw and the low-power standby state of the sensor suite, preventing voltage sags that could corrupt sensor data.
- Mermaid.js Diagram:
```
flowchart TD
    PowerIn(Tractor Battery 12V) --> Regulator(Regulator Circuit);
    Regulator -- 5V Stable --> LIDAR;
    Regulator -- 5V Stable --> Camera;
    Regulator -- 5V Stable --> GPS;
    LIDAR -- Load Change --> Regulator;
```

4. Integration with Emerging Tech

Derivative 1.7: AI-Optimized Predictive Regulation
- Enabling Description: A lightweight machine learning (ML) model, running on a co-located microcontroller, predicts imminent load changes. The model analyzes the operational state of the IC (e.g., upcoming memory access patterns, DSP calculations) to forecast current demand. The ML model's output provides a predictive feed-forward signal to the second current supply circuit (340), biasing it to pre-emptively increase or decrease the second current before the transient event occurs. This reduces output voltage deviation and improves settling time compared to a purely reactive feedback loop. The feedback loop of the '962 patent remains as the primary corrective mechanism.
- Mermaid.js Diagram:
```
sequenceDiagram
    participant ML_Model;
    participant Regulator;
    participant Load;
    ML_Model->>Regulator: Predicts load increase;
    Regulator->>Regulator: Pre-bias second current source;
    Load->>Regulator: Actual load increase occurs;
    Regulator->>Load: Supply current (minimal V_out droop);
```

5. The "Inverse" or Failure Mode

Derivative 1.8: Failsafe Low-Power Mode
- Enabling Description: The regulator includes a brown-out detection circuit that monitors the primary power supply input. If the input voltage drops below a critical threshold, the main feedback circuit (331) and second current supply (340) are disabled. A secondary, simpler low-dropout (LDO) regulator, operating in parallel and consuming minimal quiescent current, takes over. This LDO provides a lower, but stable, voltage to critical IC components (e.g., a real-time clock or non-volatile memory controller) to allow for a graceful shutdown or preservation of state. The pass device (350) is forced into a high-impedance state by a pull-up resistor on its gate.
- Mermaid.js Diagram:
```
stateDiagram-v2
    state "Normal Operation" as Normal {
      [*] --> Active
      Active: '962 regulator enabled
    }
    state "Failsafe Mode" as Failsafe {
      [*] --> LowPower
      LowPower: Parallel LDO enabled
      LowPower: '962 regulator disabled
    }
    Normal --> Failsafe: Input Voltage < V_threshold
    Failsafe --> Normal: Input Voltage > V_reset
```

Derivatives Based on Claim 14: Means-Plus-Function

1. Material & Component Substitution

Derivative 14.1: Micro-Electro-Mechanical System (MEMS) Current Supply Means
- Enabling Description: The "first current supply means" for providing a constant current is realized as a MEMS-based resonant current source. A piezoelectric cantilever resonates at a fixed frequency, driven by a reference clock. The periodic strain generates a stable AC charge, which is rectified and filtered to produce a highly stable, temperature-insensitive DC current. This provides a more robust and precise "first current" than a traditional semiconductor current mirror, especially in harsh environments.
- Mermaid.js Diagram:
```
graph TD
    A[Reference Clock] --> B{Piezoelectric Resonator};
    B --> C(Rectifier & Filter);
    C --> D[Substantially Constant I_first];
    D --> E(Second Current Path);
```

2. Operational Parameter Expansion

Derivative 14.2: Nanoscale Quantum Dot Regulator
- Enabling Description: The "means for supplying current to said load" is a single-electron transistor (SET) pass device, and the "second current supply means" is a quantum dot array. The system operates at millikelvin temperatures. The gate of the feedback transistor is held at a constant voltage that corresponds to a specific quantum energy level. The output voltage is sensed, and this voltage shift alters the tunneling probability through the quantum dot array of the "second current supply means". This, in turn, modulates the charge on the gate of the SET pass device, controlling the flow of single electrons to the load with extreme precision. This is applicable for regulating power to individual quantum bits (qubits).
- Mermaid.js Diagram:
```
sequenceDiagram
    participant Output;
    participant "Quantum Dot Array (Second Current Means)";
    participant "SET (Pass Means)";
    Output->>"Quantum Dot Array (Second Current Means)": V_out changes;
    "Quantum Dot Array (Second Current Means)"->>"SET (Pass Means)": Modulates SET gate charge;
    "SET (Pass Means)"->>Output: Controls single-electron current;
```

3. Cross-Domain Application

Derivative 14.3: Automotive - EV Battery Cell Balancing
- Enabling Description: The entire regulator circuit is miniaturized and applied to each individual cell within an electric vehicle battery pack. The "load" is a bypass resistor. The "feedback means" maintains a constant reference voltage corresponding to the ideal cell voltage. The "second current supply means" senses the actual cell voltage. If the cell voltage exceeds the reference, the "means for supplying current" (the pass device) shunts a load current through the bypass resistor, bleeding off excess charge until the cell voltage matches the reference. This provides active, continuous balancing during charging and discharging cycles.
- Mermaid.js Diagram:
```
flowchart LR
    Cell(Battery Cell) -- V_cell --> V_Sense;
    V_Ref(Reference Voltage) --> Comparator;
    V_Sense --> Comparator;
    Comparator --> Pass_Means(Pass Device);
    Pass_Means -- I_shunt --> Bypass_Resistor;
    Cell -- I_shunt_path --> Pass_Means;
```

Combination Prior Art Scenarios

Combination 1: Integration with RISC-V Power Management ISA Extension
- Scenario: An implementation of the '962 regulator is integrated into a System-on-Chip (SoC) featuring a processor core based on the open-source RISC-V instruction set architecture (ISA). A custom, non-standard ISA extension is defined for power management. A VREG_SET_TARGET instruction allows software to dynamically adjust the reference voltage used by the feedback circuit's differential amplifier (e.g., 534 in Fig. 5), enabling dynamic voltage and frequency scaling (DVFS). A VREG_GET_STATUS instruction reads the output of the second current supply circuit (540), providing software with a real-time proxy for the current load on the processor core.
- Prior Art Basis: The '962 patent combined with the public specifications of the RISC-V ISA. The novelty lies in the specific ISA extension linking software control directly to the analog regulator's core components.
Combination 2: Open-Source PMBus Interface for Digital Control
- Scenario: The '962 regulator's analog core is wrapped with a digital control interface that conforms to the open-source Power Management Bus (PMBus) standard. An ADC measures the regulator's output voltage (e.g., at node 560), and a DAC controls the reference voltage input to the feedback circuit (534). This allows an external system controller to monitor the regulator's performance, set the target output voltage, and define fault thresholds (over-voltage, under-voltage) using standard PMBus commands over an I2C/SMBus physical layer.
- Prior Art Basis: The '962 patent combined with the publicly available PMBus specification. The combination makes the analog circuit digitally addressable and configurable using an industry-standard protocol.
Combination 3: MQTT-Based IoT Monitoring via an ESP32 Co-processor
- Scenario: The voltage regulator described in the '962 patent is used to power an IoT sensor node. A low-cost ESP32 microcontroller, an open-source hardware and software platform, is integrated as a monitoring co-processor. The ESP32's ADC periodically samples the regulator's output voltage (at node 360) and the control voltage at the pass device gate (node 351). This data is formatted into a JSON payload and published to an MQTT broker over Wi-Fi, using the open MQTT protocol. This allows for remote, real-time monitoring of the regulator's health and the load's power consumption profile.
- Prior Art Basis: The '962 patent combined with the open specifications for the ESP32 hardware platform and the MQTT communication protocol. The invention is the system-level integration for remote monitoring of the regulator's internal state.