Actuator Drive Stage With Dynamic Quiescent Current Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing drive devices for actuators in optical systems face challenges with high quiescent current leading to increased waste heat and reduced bandwidth, which is not tolerable for precise actuator control in microlithography applications.
Innovation Solution
A drive device with a provision to dynamically set the quiescent current based on specific dynamic requirements, allowing for increased quiescent current only when high dynamic requirements are present to ensure fast actuator response, and reducing it otherwise to minimize waste heat.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a class A amplifier is used as an output stage for precise actuator control, then signal distortion is reduced, but quiescent current increases leading to high waste heat
Solution Approach 1:
The patent applies dynamics by making the quiescent current of the class A amplifier adjustable rather than fixed. The provision device dynamically sets the quiescent current based on the specific dynamic requirements of the actuator, allowing the system to adapt between high precision mode (higher quiescent current) and energy saving mode (lower quiescent current), thus resolving the contradiction between control precision and energy loss.
Solution Approach 2:
The patent changes the parameter of quiescent current from a fixed value to a dynamically adjustable parameter. By using a provision device that sets the quiescent current according to actuator dynamics requirements, the system can optimize the balance between signal distortion reduction (requiring higher quiescent current) and waste heat reduction (requiring lower quiescent current).
2Speed
If the quiescent current of the class A amplifier is increased, then the bandwidth and reaction time of the actuator improve, but power loss increases significantly
Solution Approach 1:
The patent makes the quiescent current dynamic by introducing a provision device that adjusts it based on the actuator's specific dynamic requirements. When fast reaction time is needed, the quiescent current is increased; when energy efficiency is prioritized, it is reduced. This dynamic adjustment resolves the contradiction between speed and energy loss.
Solution Approach 2:
The provision device periodically assesses the dynamic requirements of the actuator and adjusts the quiescent current accordingly. This periodic adjustment allows the system to maintain high performance only when necessary, reducing overall power loss while ensuring adequate reaction time when dynamic performance is required.
3Loss of energy
If the quiescent current is reduced to minimize waste heat, then power loss decreases, but the bandwidth and reaction time of the actuator are reduced
Solution Approach 1:
The patent resolves this contradiction by making the quiescent current dynamically adjustable. The provision device monitors the actuator's dynamic requirements and adjusts the quiescent current to maintain adequate reaction time only when necessary, allowing the system to operate at lower power consumption during static or low-dynamic conditions while ensuring high performance when needed.
Solution Approach 2:
The patent changes the quiescent current parameter from a fixed low value to a dynamically adjusted value. The provision device modifies this parameter based on real-time assessment of actuator dynamics requirements, ensuring that the system maintains sufficient bandwidth and reaction time only when dynamically required, thereby minimizing overall power loss and waste heat generation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The drive device achieves reduced power loss and waste heat, enabling more efficient actuator control and potentially simplifying the cooling concept for optical systems.
Implementation Method 1
an output stage, which is configured to amplify an input voltage using a quiescent current of the output stage into a drive voltage for the actuator
Implementation Method 2
a provision device, which is configured to set the quiescent current for the output stage in dependence on a specific dynamic requirement for the output stage
Implementation Method 3
A MEMS actuator (MEMS; microelectromechanical system) or a PMN actuator (PMN; lead magnesium niobate) can be used as an actuator
Data Source
AI summary
A drive device for driving at least one actuator for actuating an optical element of an optical system, wherein the drive device comprises an end stage configured to boost an input voltage using a quiescent current of the end stage to a drive voltage for the actuator. The drive device also comprises a supply device configured to adjust the quiescent current for the end stage depending on a specific dynamics request for the end stage.