Operating characteristics, Fm/if amplifier/demodulator circuit tda1576t – Philips TDA1576T User Manual
Page 8
1998 Nov 18
8
Philips Semiconductors
Product specification
FM/IF amplifier/demodulator circuit
TDA1576T
OPERATING CHARACTERISTICS
V
P
= 8.5 V; f
IF
= 10.7 MHz; R
S
= 60
Ω
; f
m
= 400 Hz with
∆
f =
±
22.5 kHz; 50
µ
s de-emphasis (C
8-9
= 6.8 nF);
T
amb
= 25
°
C and measurements taken in Fig.1; unless otherwise specified. The demodulator circuit is adjusted at
minimum second harmonic distortion with V
iIF
= 1 mV.
Standby switch; see Fig.9
V
5
input voltage for FM on
;
V
19
= 0.3 V
2.4
2.5
−
V
input voltage for FM off
−
2.9
3
V
linear range
−
350
−
mV
I
5
input current
V
5
= 0 to 2 V
−
−
−
100
µ
A
V
5
= 3.5 to 15 V
−
−
1
µ
A
temperature dependence
FM on (3.5V
BE
)
−
7
−
mV/K
FM off (5V
BE
)
−
10
−
mV/K
Supply voltage smoothing
V
1-2
internal voltage drop
proportional to
V
1
−
3V
BE
80
210
400
mV
R
1-2
internal resistor
5.8
8.3
10.8
k
Ω
SYMBOL
PARAMETER
CONDITIONS
MIN.
TYP.
MAX.
UNIT
IF amplifier and demodulator
V
iIF(rms)
input sensitivity (RMS value)
−
3 dB before limiting
14
22
35
µ
V
S/N = 26 dB
−
10
−
µ
V
S/N = 46 dB
−
55
−
µ
V
V
oAF(rms)
AF output voltage (RMS value)
60
67
75
mV
V
oN
noise voltage for V
iIF
= 0 (RMS value;
pins 8 and 9)
R
S
= 300
Ω
;
f = 250 to 15000 Hz
−
900
−
µ
V
weighted noise voltage
in accordance with
“DIN 45405”
−
2
−
mV
S/N
signal-to-noise ratio (pins 8 and 9)
V
iIF
= 1 mV (RMS);
see Fig.3
−
72
−
dB
α
AM
AM suppression
V
iIF
= 0.5 to 200 mV;
FM: 70 Hz;
±
15 kHz;
AM: 1 kHz; m = 30%
−
50
−
dB
α
FM
FM suppression for FM off
V
iIF
= 500 mV; V
5
= 3 V
80
−
−
dB
∆
V
8, 9
AFC shift in relation to minimum second
harmonic distortion
α
2H
V
iIF
= 0.03 to 500 mV
−
25
−
mV
DC offset at second harmonic distortion
operating
−
0
±
100
mV
mute or FM off
−
0
±
50
mV
α
3H
distortion for third harmonic
−
0.65
−
%
RR
ripple rejection V
ripple
= 200 mV on V
P
f = 100 Hz
43
48
−
dB
SYMBOL
PARAMETER
CONDITIONS
MIN.
TYP.
MAX.
UNIT
V
3, 7
V
3, 7(max)
-----------------------
0.9
=
V
5
T
∆
-------