Month: June 2022
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Blown LM358P due to transients
An LM358p is a dual opamp IC which I used in a single supply configuration. I drive the LM358 just shy of its absolute maximum voltage which is +30V. So I gave I supplied 28.8V (+-0.1V). It works flawless but the power supply is a Meanwell switching supply which introduces transient when plugging into the…
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FAKE BD139 NPN transistors
I have recently found out that there are FAKE transistors in the market. I have a built a circuit design and when I bought the transistor from the Lajpat rai market in Delhi; I assembled the circuit on a test bench for measurements. But I was surprised that the BD139 did not work with 10mA…