U4082B

Manufacturer Part NumberU4082B
DescriptionLow-Voltage Voice-Switched IC for Hands-Free Operation
ManufacturerATMEL Corporation
U4082B datasheet
 


1
Page 1
2
Page 2
3
Page 3
4
Page 4
5
Page 5
6
Page 6
7
Page 7
8
Page 8
9
Page 9
10
Page 10
11
12
13
14
15
16
17
18
19
20
21
22
Page 1/22

Download datasheet (170Kb)Embed
Next
Low-Voltage Voice-Switched IC for Hands-Free Operation
Description
The low-voltage voice-switched speakerphone circuit,
U4082B, incorporates the wide range of functions listed
below. Versatility of the device is further enhanced by
giving access to internal circuit points. The block diagram
(figure 1) shows amplifiers, level detectors, transmit and
receive attenuators operating in complementary func-
tions, background noise monitors, chip disable, dial tone
Features
D Low-voltage operation: 3 to 6.5 V
D Attenuator gain range between transmit and
receive: 52 dB
D Four point signal sensing for improved sensitivity
D Monitoring system for background-noise level
D Microphone amplifier gain adjustable
D Mute function
Block Diagram
MIC
11
MICO
+
V
B
12
MUTE
Background
16
noise monitor
CPT
18
TLO2
19
RLO2
4
V
S
28
GND
400 W
3
CD
15
V
B
Ordering Information
Extended Type Number
U4082B–MFL
Rev. A2, 12-Feb-01
detector and mute function. Due to low-voltage opera-
tion, it can be operated either by a low supply or via a
telephone line requiring 5.5 mA typically. Also featured
is stand-alone operation through a coupling transformer
(Tip and Ring) or in conjunction with a handset speech
network, as shown in figure 2.
D Chip disable for active/standby operation
D On-board filter
D Dial tone detector
D Compatible with U4083B speaker amplifier
Benefits
D Fast channel switching allows quasi duplex operation
D Proper operation in noisy surrounding
10
17
TLI2
9
TI
8
TO
7
HTI
T-attenuator
+
V
V
S
B
AGC
Level
Attenuator
detectors
control
Dial tone
detector
+ –
V
B
R-attenuator
14
20
RLI2 RECO
22
21
RI
13
VCI
C
T
Figure 1. Block diagram
Package
SO28
Taped and reeled
U4082B
6
HTO–
5
+
HTO+
V
B
27
CPR
Background
noise monitor
23
TLI1
Level
25
detectors
RLO1
24
TLO1
U 4082 B
Filter
2
+1
FI
26
RLI1
1
PD
93 7766 e
Remarks
1 (22)

U4082B Summary of contents