Siborg Systems Inc. and the Institute of Automation and Electrometry of the Russian Academy of Sciences in Novosibirsk, Russia, has been working over the past two years in creating a new model of the LCR-Reader.
“Smart Tweezers gives the ability for quick and highly accurate evaluations of SMT components,” says Michael Obrecht, the R&D director at Siborg, “For the ST-5S model, the basic accuracy is about %. Our goal in this project was to reduce the cost of the required components and PCB complexity, and, therefore, manufacturing cost of the device.”
There were two approaches taken aiming for manufacturing cost reduction: the traditional Smart Tweezers approach using a sinusoidal small-signal test and a response of the measured device to a voltage step signal. The first method has eventually led to the LCR-Reader that was released in June-August of and is currently priced at $200.
Further advancements in technology and available ICs allows the device to have a 100 KHz test frequency. This is integral to testing small inductances and Equivalent Series Resistance (ESR) measurements. The ESR value is crucial for testing high value electrolytic capacitances, both tantalum and aluminum.
The ESR values on aluminum and tantalum electrolytic capacitors with non-solid electrolyte can measure up to several ohms. ESR values also tend to increase with frequency due to the effects of the electrolyte. This increase of ESR values can create serious problems in Aluminum electrolytic capacitors. Though these problems are normal, large ripple currents or high temperatures can intensify the aging. The increase can be enough to cause circuit malfunction or even damage the component, despite the measured values staying withing the tolerance range of the circuit.
“We tried various circuit designs to implement a higher test frequency, but this causes battery life issues because they drew too much power. But as technology progressed, better Li-Ion batteries and new ICs (integrated circuits) meant we didn’t have to forfeit battery life for the higher frequency.” says the Team Lead Valentin Litvintsev, at the Institute of Automation and Electrometry of the Russian Academy of Sciences in Novosibirsk.