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STLC3055N

5

APPENDIX A

5.1 STLC3055N Test Circuits

Referring to the application diagram shown in fig. 9 of the STLC3055N datasheet and using as external

components the Typ. Values specified in the "External Components" Tables 10 and 11 (pages 11, 12) find

below the proper configuration for each measurement.

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

DC Loop Holding Circuit GH-1" or equivalent.

Figure 11. 2W Return Loss

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

Figure 12. THL Trans Hybrid Loss

THL = 20Log|Vrx/Vtx|

TIP

RING

RX

TX

STLC3055N

application

circuit

W&G GH1

Zref

E

Vs

1Kohm

1Kohm

100

µF

100mA

DC max

Zin = 100K

200 to 6kHz

600ohm

100

µF

TIP

RING

RX

TX

STLC3055N

application

circuit

W&G GH1

Vrx

Vtx

100

µF

100

µF

100mA

DC max

Zin = 100K

200 to 6kHz

600ohm