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6
Lucent Technologies Inc.
Data Sheet
February 1998
T7502 Dual PCM Codec with Filters
Transmission Characteristics
(continued)
ac Transmission Characteristics
Unless otherwise noted, the analog input is a 0 dBm0, 1020 Hz sine wave; the input amplifier is set for unity gain.
The digital input is a PCM bit stream equivalent to that obtained by passing a 0 dBm0, 1020 Hz sine wave through
an ideal encoder. The output level is sin(x)/x-corrected.
Table 5. Absolute Gain
Table 6. Gain Tracking
Table 7. Distortion
Parameter
Symbol
EmW
Test Conditions
Signal input of 0.775 Vrms A-law
Min
–0.25
Typ
—
Max
0.25
Unit
dBm0
Encoder Milliwatt
Response (transmit gain
tolerance)
Decoder Milliwatt
Response (receive gain
tolerance)
DmW
Measured single-ended relative to
0.775 Vrms A-law,
PCM input of 0 dBm0 1020 Hz
RL = 10 k
–0.25
—
0.25
dBm0
Parameter
Symbol
GT
X
Test Conditions
+3 dBm0 to –37 dBm0
–37 dBm0 to –50 dBm0
+3 dBm0 to –37 dBm0
–37 dBm0 to –50 dBm0
Min
–0.25
–0.50
–0.25
–0.50
Typ
—
—
—
—
Max
0.25
0.50
0.25
0.50
Unit
dB
dB
dB
dB
Transmit Gain Tracking Error
Sinusoidal Input
Receive Gain Tracking Error
Sinusoidal Input
GT
R
Parameter
Symbol
SD
X
Test Conditions
Min
35
29
25
35
29
25
—
Typ
—
—
—
—
—
—
—
Max
—
—
—
—
—
—
–38
Unit
dB
dB
dB
dB
dB
dB
dBm0
Transmit Signal to Distortion
A-law +3 dBm0
≤
VF
X
I
≤
–30 dBm0
A-law –30 dBm0
≤
VF
X
I
≤
–40 dBm0
A-law –40 dBm0
≤
VFxI
≤
–45 dBm0
A-law +3 dBm0
≤
VF
R
O
≤
–30 dBm0
A-law –30 dBm0
≤
VF
R
O
≤
–40 dBm0
A-law –40 dBm0
≤
VF
R
O
≤
–45 dBm0
200 Hz—3400 Hz, 0 dBm0 input,
output any other single
frequency
≤
3400 Hz
200 Hz—3400 Hz, 0 dBm0 input,
output any other single
frequency
≤
3400 Hz
Transmit or receive, two frequencies
in the range (300 Hz—3400 Hz)
at –6 dBm0
Receive Signal to Distortion
SD
R
Single Frequency Distortion,
Transmit
SFD
X
Single Frequency Distortion,
Receive
SFD
R
—
—
–40
dBm0
Intermodulation Distortion
IMD
—
—
–42
dBm0