TEA1085 Philips Semiconductors, TEA1085 Datasheet - Page 18

• Manufacturer Part Number: TEA1085
• Description: Listening-in circuit for line-powered telephone sets
• Manufacturer: Philips Semiconductors

Philips Semiconductors
March 1992
Larsen limiter preamplifier
G
f
f
G
G
G
Larsen limiter detector
V
G
V
V
t
t
t
t
V
SYMBOL
p1
p2
LIr
ad
LAa
LAr
G
DCA
THL1
THL2
LLC
Listening-in circuit for line-powered
telephone sets
v0
B
v
v
v
V
v
LLC
-V
DTI
operational amplifier
voltage gain
gain adjustment range
voltage to current convertor
DC offset voltage
voltage gain from DTI to DCA
DC voltage at THL1
DC voltage at THL2
dynamic behaviour with a
burst at DTI
listen-in release time
attack delay time
Larsen attack time
Larsen release time
DC voltage at LLC
reduction of V
Larsen mode
gain reduction
open-loop gain
1st pole
2nd pole
unity gain bandwidth
V
0 to 100 mV (RMS value)
V
0 to 1 V (RMS value)
V
100 mV to 0 mV (RMS
value)
DTI
DTI
DTI
jumps from
jumps from
jumps from
PARAMETER
LLC
to attack
f = 3 kHz;
R26 = 10 k ;
R29 = 4 M
V
V
f = 3 kHz
R35 = 51 k
R34 = 100 k
f = 3 kHz; see Fig.15
see Fig.15(a)
see Fig.15(b)
see Fig.15(b);
V
see Fig.15(b)
V
V
BB
DTI
DTI
DTI
LLC
= 100 mV(RMS);
= 100 mV(RMS)
= 0 V
= 0.7 V
CONDITIONS
V
DTI
= 1 V
18
51
30
tbf
1.8
1.8
tbf
100
tbf
1.75
0.59
60
25
MIN.
TEA1085; TEA1085A
92
120
3.3
4
52
1
1.25
1.25
40
160
120
20
250
1.9
0.63
tbf
0.8
TYP.
Preliminary specification
53
52
tbf
1.33
1.33
tbf
200
tbf
tbf
2.0
0.68
tbf
25
MAX.
dB
Hz
MHz
MHz
dB
dB
mV
dB
V
V
ms
ms
ms
ms
ms
V
V
dB
UNIT