FS9952_LP2

Open-Short Test

ONEK

SMV

AGND

_

+

RA

50k

RB

1k

R17

900k

R19

1k

PTC

J8

J6

Rx

VREF

0.4V

FS9952

V/Ohm

COM

Diagram 30 Open-Short Test

When doing the open-short test, the inner of IC will generate 0.4V voltage (relative to AGND) that is output from

R19 and is added to open-short measuring point through PTC. J6 and J8 are mode switches that are close

during doing the open-short test. Rx gets voltage VRx, and enters IC through R17. From the diagram we know

that

Rx=（R19+PTC）/50

So, the resistance value of PTC will influence the upper limit of open-short test resistance. When not connect to

PTC, if R22 is 1kΩ, then the resistance of the buzzer sound is smaller than 30Ω.

AC Large Current Clamp Meter Measurement Circuit

5 SA

30 AGND

FS9952

RL

VR

R

R29

100k

Diagram 31 AC Large Current Measurement

Triode hFE Test

10

200k

VDDA

E

C

B

R30

100k

ADP

Diagram 32 PNP-type Triode

Rev. 1.2

30/34