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STLC5048

APPENDIX A

STLC5048 absolute gains in kit with L3235N/STLC3080

Figure 8. STLC5048 in kit with STLC3080 AC application diagram.

Figure 9. STLC5048 in kit with L3235N AC application diagram.

In Fig.8 is shown the application diagram of the STLC5048 in kit with the STLC3080 SLIC. The figure is related

to the AC path as the STLC5048 doesn't perform any DC processing.

The only DC feature performed by STLC5048 is the Off-Hook and Limitation Threshold programmability.

The same application diagram for the AC processing can be applied to the kit with the L3235N (as shown in Fig.

9): the only differences are the following:

The scaling factor of the Iline is 50

Rs value is 4.1 Kohm.

The imoedance synthesis is fully performed by STLC5048; the L3235N SLIC (or the STLC3080) used in kit with

the STLC5048 just splits the AC/DC component of Iline, scales it and traduces it into a voltage via RS.

As shown in Fig. 3, the scaled current is converted into a voltage through the external resistor Rs = 4100 Ohm

(8200 Ohm for the STLC3080): this value is fixed (i.e. independent on the administration): the attenuation be-

tween VLINE and VFXI is dependent on the administration.

Considering the TX gain we can proceed as follows for the gain calculation:

TXG = 0dB

GX = 0dB

GRX

TIP

RS

CAC

ILTF

RDC

D00TL472

8200

Ω

RING

VFRO

VFXI

GTX

CHANNEL

FILTER

ECO

CANCELING

Z

SYNTHESIS

CHANNEL

FILTER

+

+

RX

DR

DX

2

-1

1

Zadm

Iline

TX

1

STLC5048

GRX

TIP

RPC

CAC

IL

D00TL473

4100

Ω

RING

VFRO

VFXI

GTX

CHANNEL

FILTER

ECO

CANCELING

Z

SYNTHESIS

CHANNEL

FILTER

+

+

RX

DR

DX

2

-1

1

Zadm

Iline

TX

1

STLC5048