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STLC1512

noise floor which will degrade the SNDR of the re-

ceive signal.

The same is true of the transmit signal. If the signal is

undistorted it will show up out of band in the receive

path and will not degrade SNDR. However, if the

transmit signal is distorted by the cross-talk mecha-

nism it will show up in the receive band and could re-

duce the SNDR.

The cross-talk numbers are specified from output to

output under maximum gain conditions.

4.2 Power Amplifier Performance

Specifications

The power amplifier must be specified with all of the

external components in the application diagram.

Without these components the amplifier will not func-

tion correctly. Specifications that are measured at the

chip are specified as such in the comments.

Table 3 contains the conditions over which the spec-

ifications in Table 4 apply. The limits on the specifica-

tions in Table

are valid over all of the ranges

specified in Table 3. The nominal values of the spec-

ification occur at the nominal value of all of the condi-

tions in Table 3 unless otherwise specified.

...

Table 2. Chip Performance Specifications

Description

min

nom

max

Units

Comments

Rx Cross-Talk into Tx

Undistorted

-55

dB

Measured from the active low pass filter

output in the receive path to tip and ring.

Rx Cross-Talk into Tx

Distorted

-73

dB

Measured from the active low pass filter

output in the receive path to tip and ring.

Tx Cross-talk into Rx

Undistorted

-50

dB

Measured from tip and ring to the active

low pass filter output with the maximum

gain setting in place.

Tx Cross-talk into Rx

Distorted

-86

dB

Measured from tip and ring to the active

low pass filter output with the maximum

gain setting in place.

Table 3. Power Amplifier Performance Limits

Description

min

nom

max

Units

Gain

19.9

20.1

20.3

dB

Ambient Temperature

-40

27

85

Line Impedance

80

100

160

W

A nominal chip will have no problem

driving 200

Ω or 50 Ω.

Supply voltage for TXVCC

4.75

5.0

5.25

V

<1>Nominal specifications are for nominal bias and process

<2>Maximum and minimum specifications are for worst case process and bias conditions