Component identification - help

[k.valentino]

Hi, need help with identification one transistor  (or maybe voltage regulator). I need to replace it.

MMBT2907A

The transistor is burned and is from car's gas analyzer machine that have problem with the display.

[cortex_m0]

MMBT2907A makes sense, if the theory of the circuit is to vary the LM324 negative supply rail with changes in temperature.

I'm not sure why you'd do that, but it's a circuit I could imagine working.

[SpecialK]

Is it really burned?

The SMD code app on my phone suggests 2.5V LDO. 

I guess I wouldn't mind a look at the complete board.

[k.valentino]

Is it really burned?

The SMD code app on my phone suggests 2.5V LDO. 

I guess I wouldn't mind a look at the complete board.

Thanks for the answers! Yes, the transistor is burned (have fuga).

[bob91343]

I would guess the equivalent would be 2N2907A which is in TO-18 package.