Techniques for electrostatic discharge (ESD) protection for amplifiers and other circuitry employing charge pumps. In an exemplary embodiment, a Vneg switch coupling a second flying capacitor node to a negative output voltage node is closed in response to an ESD event being detected between a supply voltage node and the negative output voltage node. A ground switch coupling a ground node to the second flying capacitor node is closed in response to an ESD event being detected between the ground node and the negative output voltage node. The Vneg switch is further closed in response to the ESD event being detected between the ground node and the negative output voltage node. Further techniques are disclosed for providing on-chip snapback clamps at the output of a power amplifier coupled to the charge pump to protect against ESD events as defined by the standard IEC 61000-4-2.

Charge pump electrostatic discharge protection

Super-resolution time delay and integrate (TDI) imaging processing and systems for providing same utilize imaging geometry configured such that a predictable sub-pixel component of the frame-to-frame image motion can be used to construct a high-resolution output image from multiple under-sampled low-resolution input images.

System and method for super-resolution digital time delay and integrate (TDI) image processing

Dealing with high-speed image acquisition and processing systems, the speed of operation is often limited by the amount of available light, due to short exposure times. Therefore, high-speed applications often use line-scan cameras, based on charge-coupled device (CCD) sensors with time delayed integration (TDI). Synchronous shift and accumulation of photoelectric charges on the CCD chip - according to the objects’ movement - result in a longer effective exposure time without introducing additional motion blur. This paper presents a high-speed color line-scan camera based on a commercial complementary metal oxide semiconductor (CMOS) area image sensor with a Bayer filter matrix and a field programmable gate array (FPGA). The camera implements a digital equivalent to the TDI effect exploited with CCD cameras. The proposed design benefits from the high frame rates of CMOS sensors and from the possibility of arbitrarily addressing the rows of the sensor’s pixel array. For the digital TDI just a small number of rows are read out from the area sensor which are then shifted and accumulated according to the movement of the inspected objects. This paper gives a detailed description of the digital TDI algorithm implemented on the FPGA. Relevant aspects for the practical application are discussed and key features of the camera are listed.

High-speed line-scan camera with digital time delay integration

Efficient reversible data hiding for color filter array images

With the development of Computer-aided Diagnosis (CAD) and image scanning techniques, Whole-slide Image (WSI) scanners are widely used in the field of pathological diagnosis. Therefore, WSI analysis has become the key to modern digital histopathology. Since 2004, WSI has been used widely in CAD. Since machine vision methods are usually based on semi-automatic or fully automatic computer algorithms, they are highly efficient and labor-saving. The combination of WSI and CAD technologies for segmentation, classification, and detection helps histopathologists to obtain more stable and quantitative results with minimum labor costs and improved diagnosis objectivity. This paper reviews the methods of WSI analysis based on machine learning. Firstly, the development status of WSI and CAD methods are introduced. Secondly, we discuss publicly available WSI datasets and evaluation metrics for segmentation, classification, and detection tasks. Then, the latest development of machine learning techniques in WSI segmentation, classification, and detection are reviewed. Finally, the existing methods are studied, and the application prospects of the methods in this field are forecasted. 

A comprehensive review of computer-aided whole-slide image analysis: from datasets to feature extraction, segmentation, classification and detection approaches

Volumetric imaging of dynamic processes with microscopic resolution holds a huge potential in biomedical research and clinical diagnosis. Using supercontinuum light sources and high numerical aperture (NA) objectives, optical coherence tomography (OCT) achieves microscopic resolution and is well suited for imaging cellular and subcellular structures of biological tissues. Currently, the imaging speed of microscopic OCT (mOCT) is limited by the line-scan rate of the spectrometer camera and ranges from 30 to 250 kHz. This is not fast enough for volumetric imaging of dynamic processes in vivo and limits endoscopic application. Using a novel CMOS camera, we demonstrate fast 3-dimensional OCT imaging with 600,000 A-scans/s at 1.8 µm axial and 1.1 µm lateral resolution. The improved speed is used for imaging of ciliary motion and particle transport in ex vivo mouse trachea. Furthermore, we demonstrate dynamic contrast OCT by evaluating the recorded volumes rather than en face planes or B-scans. High-speed volumetric mOCT will enable the correction of global tissue motion and is a prerequisite for applying dynamic contrast mOCT in vivo. With further increase in imaging speed and integration in flexible endoscopes, volumetric mOCT may be used to complement or partly replace biopsies.

Microscopic optical coherence tomography (mOCT) at 600 kHz for 4D volumetric imaging and dynamic contrast

This paper introduces a novel concept for arbitrating the access of multiple asynchronous data sources to a shared communication bus, while adding a timestamp, which represents high precision temporal information, to sensor information. This principle is based upon an arbiter serving uncorrelated inputs and generating a stream of data packets. The information contained in the data packets consists of the address information identifying the data source, data from the source and a timestamp value with respect to the occurrence of the bus request (event) generated by the corresponding data source. To enhance the adaptability to particular applications, the time resolution can be varied. The proposed concept has the advantage of delivering a sorted output data stream of nearly concurrent events (labeled with the same timestamp) which is very advantageous for consecutive data processing. Furthermore, this arbitration method is very efficient as it enables the utilization of the maximum output transfer rate for a given clock frequency. A potential usage in asynchronous vision chips is intended. This concept is demonstrated using an asynchronous vision chip containing 512 autonomous optical sensor elements.

Multiple Input Digital Arbiter with Timestamp Assignment for Asynchronous Sensor Arrays

To identify a fault state, for example, a break in a supply line, while maintaining operational reliability, a circuit configuration for identifying a fault state includes a first transistor of a normally on type having a voltage that pinches off its channel at a control input in a normal operating state and the channel of the transistor having low impedance in a fault state. As a result, preferably, the output of a linear amplifier stage can be connected to the intact potential in the event of a break in the supply line.

Circuit configuration for identifying a fault state

Today, printing products which must meet highest quality standards, e.g., banknotes, stamps, or vouchers, are automatically checked by optical inspection systems. Typically, the examination of fine details of the print or security features demands images taken from various perspectives, with different spectral sensitivity (visible, infrared, ultraviolet), and with high resolution. Consequently, the inspection system is equipped with several cameras and has to cope with an enormous data rate to be processed in real-time. Hence, it is desirable to move image processing tasks into the camera to reduce the amount of data which has to be transferred to the (central) image processing system. The idea is to transfer relevant information only, i.e., features of the image instead of the raw image data from the sensor. These features are then further processed. In this paper a color line-scan camera for line rates up to 100 kHz is presented. The camera is based on a commercial CMOS (complementary metal oxide semiconductor) area image sensor and a field programmable gate array (FPGA). It implements extraction of image features which are well suited to detect print flaws like blotches of ink, color smears, splashes, spots and scratches. The camera design and several image processing methods implemented on the FPGA are described, including flat field correction, compensation of geometric distortions, color transformation, as well as decimation and neighborhood operations.

Ernst Bodenstorfer

Papers

High-speed line-scan camera with digital time delay integration

Microscopic optical coherence tomography (mOCT) at 600 kHz for 4D volumetric imaging and dynamic contrast

Multiple Input Digital Arbiter with Timestamp Assignment for Asynchronous Sensor Arrays

Circuit configuration for identifying a fault state

High-performance camera module for fast quality inspection in industrial printing applications