I would like to ask an expert, what are the devices and their models in these two pictures, thank you...

KOBI

I would like to ask an expert, what are the devices and their models in these two pictures, thank you... [Copy link]

 

tagetage

Please measure the voltage of each pin of these two components.

qwqwqw2088

Seemingly simple question, but difficult to answer

qwqwqw2088

Little information,

There are too many SOT-23 packaged chip transistors now, and they are generally coded as
SOT-223 packaged chips. It stands to reason that the chip model should be printed

But some manufacturers now do not know what happened

beyond_笑谈

First draw the circuit diagram of this component and its surrounding components, determine the function of the component, and then subdivide it. Or you can preliminarily judge the component type and function by the voltage of each pin and the PN junction between the pins.

KOBI

qwqwqw2088 posted on 2024-7-2 11:32 There is little information. There are too many SOT-23 packaged chip transistors now. Generally, the SOT-223 packaged chips are marked with codes. It stands to reason that they should be printed...

Thank you, both should be transistors. I will find a model to test.

KOBI

beyond_笑谈Published on 2024-7-2 11:38 First draw the circuit diagram of this component and surrounding components, determine the function of the component and then subdivide it. Or through the voltage of each pin, the PN junction between the pins is initially...

Thank you, looking at the peripheral circuit, it should be a triode.

beyond_笑谈

KOBI posted on 2024-7-2 11:48 Thank you, looking at the peripheral circuit, it should be a triode.

If it is a transistor, it is easy to deal with. Use the diode position of the multimeter to measure the PN node to determine whether it is NPN or PNP, and then find a replacement of the corresponding type.

KOBI

Thanks to everyone for their enthusiastic help. The test results are out. The first one is a double diode and the second one is a PNP transistor. Thank you everyone...

niuyite

According to the actual circuit analysis, if the first pin in the lower left corner is grounded, it is usually an LDO. If it is not grounded and has pull-up and pull-down resistors, it is a triode or MOS tube.

秦天qintian0303

KOBI posted on 2024-7-2 11:48 Thank you, looking at the peripheral circuit, it should be a triode.

Is the second picture also a triode? This kind of packaging is indeed rare, and the middle pin is usually removed.

KOBI

Qintianqintian0303 posted on 2024-7-3 09:19 Is the second picture also a triode? This kind of package is indeed rare, and the middle pin is usually removed

风太大了

If you ask directly, no one can tell. You still have to look at the peripheral circuit and analyze whether it is a MOS tube, a triode, or a chip.