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STLC3075

5

APPENDIX A

5.1 STLC3075 Test Circuits

Referring to the application diagram shown in fig. 11 and using as external components the Typ. Values

specified in the "External Components" Tables 10 and 12 (pages 11 and 12) find below the proper config-

uration for each measurement.

All measurements requiring DC current termination should be performed using "Wandel & Goltermann

DC Loop Holding Circuit GH-1" or equivalent.

Figure 13. 2W Return Loss

2WRL = 20Log(|Zref + Zs|/|Zref-Zs|) = 20Log(E/2Vs)

Figure 14. THL Trans Hybrid Loss

THL = 20Log|Vrx/Vtx|

TIP

RING

RX

TX

STLC3075

application

circuit

W&G GH1

Zref

E

Vs

1Kohm

1Kohm

100 F

100mA

DC max

Zin = 100K

200 to 6kHz

600ohm

100 F

TIP

RING

RX

TX

STLC3075

application

circuit

W&G GH1

Vrx

Vtx

100 F

100 F

100mA

DC max

Zin = 100K

200 to 6kHz

600ohm