Pogo Pin Research Articles

Astrosense – a Printed Wearalbe Electrochemical Sensor for Monitoring Cortisol in Sweat during Human Spaceflight

The In Space Manufacturing of sensors and electronics can directly addresses the logistic challenge for long-duration human spaceflight missions by reducing mission logistics mass, increase reliability, mitigate risk, while also offering a high degree of customization and tailorability. This manufacturing approach relies on additive manufacturing technologies, due to its versatility, low power consumption, automation, fast manufacturing time with low waste generation, and ability to print a variety of materials. To ensure the health and safety of crew members, developing human health portable diagnostic tools that can be manufactured during long duration missions is necessary to ensure that the crew members are monitored in real time so that countermeasures can be deployed as soon as possible. Here we report the development of Astrosense (Figure 1), a wearable wireless and fully printed platform that integrates several sensors, including, electrochemical sensor for the detection of cortisol in sweat, temperature, CO2 and humidity sensors, as well as, the required hardware required to control each individual sensor.Astrosense consists of two sections, a reusable, and a disposable section. The reusable section contains the CO2,temperature, humidity sensor, the potentiostat that controls the cortisol sensor and the printed antennas for data transmission. The cortisol sensor, sweat harvest component and printed batteries will be located on the disposable section of Astrosense, so that they can be easily replaced once the sensor is either saturated, degraded or when the batteries need to be replaced. The disposable section will interfase with the reusable section of Astrosense through several medical grade adhesives and pogo pins. This allows for the easy replacement of the cortisol sensor as well as mounting and dismounting of the device on the human skin. Figure 1

50 GHz Four-Port Coupling-Reduced Probe Card Utilizing Pogo Pins Housed in Custom Metallic Socket.

A design for a pogo-pin probe card featuring a metallic socket is proposed to eliminate signal leakage and coupling loss in a multi-port environment. The proposed metallic pogo-pin socket includes a metal wall structure between adjacent pogo pins, ensuring complete isolation. This metal wall offers an advantage in removing coupling issues between pogo pins that can occur with typical dielectric pogo-pin sockets. The designed probe card is fabricated as a prototype and verified for its performance. Measurement results using a test through line show that coupled power is minimized, providing a low-loss transmission performance of -2.14 dB to an RF chip at 50 GHz, all within a compact size. Although the dielectric spacer used to secure the pogo pins allows for some leakage, it can maintain a low coupling performance of under -15 dB in the millimeter-wave band. The prototype probe card can deliver an RF signal to a 5G circuit with a low loss of -0.7 dB at 28 GHz and -1.9 dB at 39 GHz frequency. The designed probe card is capable of transmitting multiple RF signals to the RF system without signal distortion in a multi-port environment.

Ground Based Recharging System for Electric Buses

In response to the growing demand for efficient and convenient electric vehicle (EV) charging solutions, this paper proposes a novel ground-based charging system tailored for EV buses and trucks. The system utilizes a current collector mechanism akin to pantograph charging, integrating a linear actuator with three terminals for positive, negative, and ground connections. Pogo pins, each rated at 5 amps and connected in series, are employed as connectors for reliable power transfer. The ground infrastructure consists of buried copper terminals arranged in a grid formation, covered with a silicon inductor sheet to ensure safety and durability. Upon the arrival of an EV bus/truck, a proximity sensor detects its position, prompting the driver to initiate the charging process by scanning a QR code and entering identifying information via IoT communication. Activation of the linear actuator, controlled through a relay system, establishes the power connection between the vehicle and the ground-based infrastructure. Upon completion of charging, the system is deactivated, and the vehicle can resume its journey. This paper outlines the design, operation, and potential benefits of the proposed ground-based charging system, offering a promising solution to enhance the efficiency and accessibility of EV charging for public transportation fleets.

Effect of onion-like carbon on the resistance and adhesion of pogo pins with titanium adhesive layer of varying thicknesses

A test probe is a component used to attach microchips to a semiconductor testing device. Pogo pins are one of the several types of probes available on the market. However, probes exhibit some drawbacks, such as high manufacturing costs, low test lifespan, and susceptibility to sticking. In this study, a dual-layer structure that can enhance the wear resistance and anti-sticking properties of gold (Au)-plated pogo pins, as well as overcome surface adhesion issues, is proposed. Oxygen plasma cleaning is first performed for 30 min. Subsequently, a direct current plasma of 250 W is applied to deposit a titanium (Ti) layer to enhance the adhesion of onion-like carbon (OLC) on the surface. The four thicknesses of the deposited Ti metal are 20, 30, 50, and 70 nm. Finally, extremely hard and conductive OLC with a thickness of 110 nm is deposited on the Ti/Au-plated pogo pin surface by physical vapor deposition. Results reveal that most of the area of OLC with the Ti adhesion layer remains on the substrates even after cycle testing at 200 K. Nanoindenter measurements reveal that with an increase in the Ti thickness, the probe hardness increases; in particular, at a thickness of 70 nm, the hardness is 121 % greater than that of the as-grown probe. Furthermore, under the 200 K wear test, the probe with 70 nm Ti exhibits ∼9 % reduction in surface wear in comparison with that of the as-grown probe. Finally, while the resistance of the dual-layer coated probe is greater than that of the as-grown probe at 0 K, its resistance becomes markedly less than that of the as-grown probe after undergoing a 200 K cycle test. On the basis of these results, a mechanism of adhesion, hardness, and wear resistance improvement by the OLC/Ti dual-layer structure is proposed.

Novel Design and Control of Vibratory Assembly Platform for Pogo Pin

Novel Design and Control of Vibratory Assembly Platform for Pogo Pin

Quality Assurance Test System for Assembly of STS Modules for the BM@N Experiment

The Silicon Tracking System (STS) of the BM@N experiment will be based on modules with Double-Sided microstrip Silicon Detectors (DSSD) which have been initially developed for the CBM experiment at FAIR. Each module consists of a DSSD, two front-end boards with 8 ASICs each, and a set of low-mass aluminum microcables. During the module assembly the microcables are tab-bonded to the sensor and readout ASICs. The module has 1024 channels on each side of the sensor. For the quality assurance of the ultrasonic bonding process a dedicated procedure based on the noise per channel measurements with a Pogo Pin test device was developed.

Double N Stubs for Impedance Matching Improvement of Pogo Pin Test Board at mmWave Applications

Double N Stubs for Impedance Matching Improvement of Pogo Pin Test Board at mmWave Applications

Low-Loss Pogo Pin Probe Card with a Coupling Isolation Structure up to 50 GHz

A design for a millimeter wave RF probe card that removes resonance is proposed. The designed probe card optimizes the position of the ground surface and the signal pogo pins to resolve the resonance and signal loss issues that occur when connecting a dielectric socket and a PCB. At millimeter wave frequencies, the height of the dielectric socket and pogo pin matches the length of half a wavelength, allowing the socket to act as a resonator. When the leakage signal from the PCB line is coupled to the 2.9 mm high socket with pogo pins, resonance at a frequency of 28 GHz is generated. The probe card uses the ground plane as a shielding structure to minimize this resonance and radiation loss. The importance of the signal pin location is verified via measurements in order to address the discontinuity caused by field polarity switching. A probe card fabricated using the proposed technique exhibits an insertion loss performance of −8 dB up to 50 GHz and eliminates resonance. A signal with an insertion loss of −3.1 dB can be transmitted to a system-on-chip in a practical chip test.

Nondestructive Data Acquisition Methodology for IoT Devices: A Case Study on Amazon Echo Dot Version 2

The smart speaker is becoming a common part of the modern household, which usually includes an AI-powered Intelligent Voice Assistant to communicate with its users. Amazon Echo Dot is a popular smart speaker that extends the above-stated functionality by acting as a communication hub for other Internet of Things (IoT) and mobile devices within its local network. The nature and volume of data that an Echo Dot handles make it a potential source of evidence, if one is seized for a digital forensics investigation. Researchers and practitioners have explored various techniques to extract data from these IoT devices. However, traditional methods make changes to the physical device and/or its data, which is undesirable from a digital forensics perspective. The current work focuses on developing a nondestructive methodology for extracting data from IoT devices, with Amazon Echo Dot version 2 as an example, which use embedded Multimedia Card (eMMC)/embedded Multichip Package (eMCP) chips as their primary storage. We identify all in-system programming (ISP) pins using the computed tomography (CT) Scan imagery of the main printed circuit board (PCB) of the device. We created a 3-D fixture that accommodates pogo pin connectors to create contact with the already identified ISP taps on the main PCB. The 3-D Test Probe Jig can extract data from an IoT device’s memory chip using an eMMC reader. The proposed nondestructive solution is reproducible, portable, and affordable.

Designing an IoT Agriculture Monitoring System for Improving Farmer’s Acceptance of Using IoT Technology

This paper describes Agri-Snaps, an Internet of Things (IoT) agriculture monitoring system designed to improve farmers’ acceptance of using IoT technology in their farm field. Agri-Snaps consists of four dedicated sensor circuit modules that integrate magnetic pogo pin connectors for easier assembly with the controller circuit module. This work investigated how such a design can enable the farmers to understand how 1) to assemble, 2) self-troubleshoot, and 3) maintain the monitoring system independently without requiring expertise on the farm site. User-experience testing was conducted with ten participants to validate Agri-Snaps’s viability. The results showed that those participants positively rated Agri-Snaps as attractive, easy to understand and assemble, exciting, and innovative compared to the typical agriculture monitoring systems.

OEE improvement by pogo pin defect detection in wafer probing process

OEE improvement by pogo pin defect detection in wafer probing process

Experimental Validation of a Highly Damped Deployable Solar Panel Module with a Pogo Pin-Based Burn Wire Triggering Release Mechanism

In this present work, a highly damped deployable solar panel module was developed for application in the 3 U CubeSat. The solar panel proposed herein is effective in guaranteeing the structural safety of solar cells under a launch environment owing to the superior damping characteristics achieved using multilayered stiffeners with viscoelastic acrylic tapes. A holding and release action of the solar panel was achieved by a new version of spring-loaded pogo pin-based burn wire triggering mechanism. A demonstration model of high-damping solar panel assembly was fabricated and tested to validate the effectiveness of the design. The holding and release mechanism achieved using a pogo pin was functionally tested through solar panel deployment tests under ambient room temperature and a thermal vacuum environment. The design effectiveness and structural safety of the solar panel module were validated through qualification-level launch and in-orbit environment tests.

A parasitic impedance effect study using a discharge probe for FICBE testing based on CDM waveform verification

Field Induced Charged Board Events (FICBE) experiments were conducted. The waveforms were verified using charged device model (CDM) standards. The discharge probe was constructed to determine the electrostatic discharge sensitivity of a PCB. The standard CDM current waveforms were used as a reference to ensure proper function of the discharge probe. The investigation revealed that a lower impedance of a pogo pin improved the sensitivity. The parallelizing of a pair of 2 Ω resistors reduced the parasitic inductance. Inclusion of a ferrite bead on the current sensing wires reduced the common mode noise. This test bench complies with standard CDM current waveforms.

Development of Pogo Pin-Based Holding and Release Mechanism for Deployable Solar Panel of CubeSat

CubeSats are revolutionary to the space industry and are transforming space exploration which enables the next generation of scientists and engineers to complete all phases of space missions. Deployable solar panels have been widely used for the generation of enough power in CubeSats due to their limited volume area for solar cell integration. In general, the cable cutting release mechanism have been used in 1U-3U small satellites because of its simplicity and low cost. However, this mechanism has a low constraint force and is unable to apply constraints along the in-plane and out-of-plane directions. In this study, for the improvement of the conventional cable cutting mechanism, a spring-loaded pogo pin-based nichrome burn wire holding and release mechanism (HRM) was proposed and fabricated. The pogo pin constitutes an immensely attractive function for the holding and release mechanism of solar panels because it works as an electrical interface to provide power, a separation spring to initiate the reaction force to deploy the panels, and a status switch to determine deployments. In addition, the proposed mechanism guarantees the loading capability along the in-plane and out-of-plane directions of solar panels, the synchronous release of multiple panels, and a handling simplicity that differentiates it from the conventional mechanism. The design feasibility, structural safety, and reliability of the mechanism were verified through functionality tests and launch and on-orbit environmental tests. The proposed pogo pin-based holding and release mechanism would be equally applicable for other CubeSat deployable appendages.

Capacitance-voltage profiling of MOS capacitors: A case study of hands-on semiconductor testing for an undergraduate laboratory

Catering to a large undergraduate laboratory class requires the experiments to be robust, low maintenance, and easy to set up with low cost test equipment at the disposal of most university laboratories. Most introductory undergraduate semiconductor device laboratory courses utilize packaged semiconductor integrated circuit chips to illustrate the functioning and applications of fundamental semiconductor devices such as diodes and transistors. While such methods do justice to the illustration of device concepts, the packages abstract the device physics and manufacturing and promote a “black-box” mentality towards device engineering. We have proposed and implemented a novel undergraduate device laboratory experiment, where metal oxide semiconductor capacitor (MOSCAP) devices were designed and fabricated at our university cleanroom and provided to students to perform basic capacitance-voltage profile measurements. To allow over a hundred students to simultaneously perform the experiments, we fabricated miniature test jigs that served as probe stations with spring-loaded pogo pins to make electrical contact with the devices. Using a simple op-amp based circuit that is easy for second year undergraduates to analyze, students are able to successfully extract device parameters such as substrate doping density and flat-band voltage using this experiment, and visualize the different modes of operation of a MOSCAP.

Experimental Investigation on the Feasibility of Using Spring-Loaded Pogo Pin as a Holding and Release Mechanism for CubeSat’s Deployable Solar Panels

A spring-loaded pogo pin as a holding and release mechanism of solar panels for cube satellite applications is proposed which functions as an electrical interface, a separation spring, and a status switch. The proposed mechanism has many advantages, including an increased loading capability, negligible induced shock level, synchronous release of multiple panels, and handling simplicity during integration. A demonstration model of the mechanism was fabricated and functionally tested under various test conditions such as different input voltages, different numbers of tightened nylon wires, and different temperatures (ranging from −40°C to 70°C).

Mitigating leakage errors due to cavity modes in a superconducting quantum computer

A practical quantum computer requires quantum bit (qubit) operations with low error probabilities in extensible architectures. We study a packaging method that makes it possible to address hundreds of superconducting qubits by means of coaxial Pogo pins. A qubit chip is housed in a superconducting box, where both box and chip dimensions lead to unwanted modes that can interfere with qubit operations. We analyze these interference effects in the context of qubit coherent leakage and qubit decoherence induced by damped modes. We propose two methods, half-wave fencing and antinode pinning, to mitigate the resulting errors by detuning the resonance frequency of the modes from the qubit frequency. We perform electromagnetic field simulations indicating that the resonance frequency of the modes increases with the number of installed pins and can be engineered to be significantly higher than the highest qubit frequency. We estimate that the error probabilities and decoherence rates due to suitably shifted modes in realistic scenarios can be up to two orders of magnitude lower than the state-of-the-art superconducting qubit error and decoherence rates. Our methods can be extended to different types of packages that do not rely on Pogo pins. Conductive bump bonds, for example, can serve the same purpose in qubit architectures based on flip chip technology. Metalized vias, instead, can be used to mitigate modes due to the increasing size of the dielectric substrate on which qubit arrays are patterned.

High coherence plane breaking packaging for superconducting qubits

We demonstrate a pogo pin package for a superconducting quantum processor specifically designed with a nontrivial layout topology (e.g., a center qubit that cannot be accessed from the sides of the chip). Two experiments on two nominally identical superconducting quantum processors in pogo packages, which use commercially available parts and require modest machining tolerances, are performed at low temperature (10 mK) in a dilution refrigerator and both found to behave comparably to processors in standard planar packages with wirebonds where control and readout signals come in from the edges. Single- and two-qubit gate errors are also characterized via randomized benchmarking, exhibiting similar error rates as in standard packages, opening the possibility of integrating pogo pin packaging with extensible qubit architectures.

A novel 3D-microstructured multielectrode array configuration for high-yield and high-fidelity electrophysiological recordings

A novel 3D-microstructured multielectrode array configuration for high-yield and high-fidelity electrophysiological recordings

High-Frequency Modeling and Signal Integrity Analysis of a Silicone Rubber Socket for High-Performance Package

As a demand for electrical systems with a wide data bandwidth has increased, high-performance packages ensuring high data rates, such as low power double data rate series, have become common. The need for high-performance test sockets has also emerged to test these packages. However, a conventional pogo pin socket has a limited test bandwidth due to the parasitic components arising from its spring. On the other hand, a silicone rubber socket satisfies the wide bandwidth requirement because it has low parasitic components due to high-density conductive metal powders in an elastic silicone rubber. In this paper, we propose an RLGC equivalent circuit model of a silicone rubber socket and first experimentally verify it. The proposed model is experimentally verified in the frequency domain by comparing the insertion loss obtained from the proposed model to the measurement up to 20 GHz. The proposed model is experimentally verified in the time domain by comparing the eye diagrams obtained from the proposed model to the measurement at a data rate of 12.5 Gb/s. Also, the insertion loss of the sockets with varied height, diameter, and pitch is analyzed using the proposed model. The proposed model provides physical insight of a silicone rubber socket, and it allows to determine whether a socket is reliable for testing high performance packages in a short time. It also gives us the idea how to design a high-performance test socket. Furthermore, we discuss the current capacity and life cycle of the silicone rubber socket in terms of signal integrity as well.