T7 component tester teardown

 I bought this unit for cheap on amazon.

Didnt really play with it until i wanted to check something on a vanilla NPN transistor.

 It gave a hFE of 426. 

Really ? That's a bit high, i checked with my own tester and the datasheet, they both gave around 250.

Okay, time to open it up :


The MCU is an Atmel 324 with a 16 Mhz quartz

There is a second tiny MCU a STC 8G1K08 (??)

The AL088 is maybe a step up converter circuit

The 7DA5 is probably a lithium charging circuit

V05 are TVS

Build quality is fine, just a bit of flux i cleaned up

There is also a "431" on the top right, probably a TL431 voltage reference for the ADC.


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