ATMEL U4083B

Features
•
•
•
•
•
•
•
•
Wide Operating Voltage Range: 2V to 16V
Low Current Consumption: 2.7 mA Typically
Chip Disable Input to Power Down the Integrated Circuit
Low Power-down Quiescent Current
Drives a Wide Range of Speaker Loads
Output Power Po = 250 mW at RL = 32Ω (Speaker)
Low Harmonic Distortion (0.5% Typically)
Wide Gain Range: 0 dB to 46 dB
Low-power
Audio Amplifier
for Telephone
Applications
Benefits
• Low Number of External Components
• Low Current Consumption
1. Description
The integrated circuit U4083B is a low-power audio amplifier for telephone loudspeakers. It has differential speaker outputs to maximize the output swing at low supply
voltages. There is no need for coupler capacitors. The U4083B has an open-loop gain
of 80 dB where the closed-loop gain is adjusted with two external resistors. A chip disable pin permits powering down and/or muting the input signal.
Figure 1-1.
Block Diagram
6
Vi
FC3
VS
4
5
Amp1
3
4k
2
8
Amp2
125k
VO1
4k
50k
FC2
U4083B
VO2
50k
U4083B
Bias circuit
1
CD
7
GND
Rev. 4655C–CORD–03/06
2. Pin Configuration
Figure 2-1.
Table 2-1.
Pin
2
Pinning SO8
CD
1
8
VO2
FC2
2
7
GND
FC1
3
6
VS
Vi
4
5
VO1
Pin Description
Symbol
Function
1
CD
Chip disable
2
FC2
Filtering, power supply rejection
3
FC1
Filtering, power supply rejection
4
Vi
5
VO1
6
VS
7
GND
Ground
8
VO2
Amplifier output 2
Amplifier input
Amplifier output 1
Voltage supply
U4083B
4655C–CORD–03/06
U4083B
3. Functional Description Including External Circuitry
3.1
Pin 1: Chip Disable Digital Input (CD)
Pin 1 (chip disable) is used to power down the IC to conserve power or mute the IC or both.
Input impedance at Pin 1 is typically 90 kΩ.
• Logic 0 < 0.8V
IC enabled (normal operation)
• Logic 1 > 2V
IC disabled
Figure 8-15 on page 12 shows the power supply current diagram. The change in differential gain
from normal operation to muted operation (muting) is more than 70 dB.
Switching characteristics are as follows:
• Turn-on time
ton = 12 ms to 15 ms
• Turn-off time
toff ≤2 µs
They are independent of C1, C2 and VS.
Voltages at Pins 2 and 3 are supplied from VS and, therefore, do not change when the U4083B
is disabled. The outputs, VO1 (Pin 5) and VO2 (Pin 8), turn to a high impedance condition by
removing the signal from the speaker.
When signals are applied from an external source to the outputs (disabled), they must not
exceed the range between the supply voltage, VS, and ground.
3.2
Pins 2 and 3: Filtering, Power Supply Rejection
Power supply rejection is provided by capacitors C1 and C2 at Pin 3 and Pin 2, respectively. C1 is
dominant at high frequencies whereas C2 is dominant at low frequencies (Figure 8-4 on page 8
to Figure 8-7 on page 9). The values of C1 and C2 depend on the conditions of each application.
For example, a line-powered speakerphone (telephone amplifier) will require more filtering than
a system powered by regulated power supply.
The amount of rejection is a function of the capacitors and the equivalent impedance at Pin 3
and Pin 2 (see electrical characteristic equivalent resistance, R).
Apart from filtering, capacitors C1 and C2 also influence the turn-on time of the circuit at power
up, since the capacitors are charged up through the internal resistors (50 kΩ and 125 kΩ) as
shown in the block diagram.
Figure 8-1 on page 7 shows the turn-on time versus C2 at VS = 6V, for two different C1 values.
The turn-on time is 60% longer when VS = 3V and 20% shorter when VS = 9V.
The turn-off time is less than 10 µs.
3
4655C–CORD–03/06
3.3
Pin 4: Amplifier Input Vi, Pin 5: Amplifier Output 1 VO1, Pin 8: Amplifier Output 2 VO2
There are two identical operational amplifiers. Amplifier 1 has an open-loop gain ≥ 80 dB at
100Hz (Figure 8-2 on page 7), whereas the closed-loop gain is set by external resistors, Rf and
Ri (Figure 8-3 on page 8). The amplifier is unity gain stable, and has a unity gain frequency of
approximately 1.5 MHz. A closed-loop gain of 46 dB is recommended for a frequency range of
300Hz to 3400Hz (voice band). Amplifier 2 is internally set to a gain of –1.0 dB (0 dB). The outputs of both amplifiers are capable of sourcing and sinking a peak current of 200 mA. Output
voltage swing is between 0.4V and VS – 1.3V at maximum current (Figure 8-18 on page 13 and
Figure 8-19 on page 13).
The output DC offset voltage between Pins 5 and 8 (VO1 – VO2) is mainly a function of the feedback resistor, Rf, because the input offset voltages of the two amplifiers neutralize each other.
Bias current of Amplifier 1 which is constant with respect to V s , flows out of Pin 4 (Vi ) and
through Rf, forcing VO1 to shift negative by an amount equal to RfIIB and VO2 positive to an equal
amount.
The output offset voltage specified in the electrical characteristics is measured with the feedback
resistor (Rf = 75 kΩ) shown in the typical application circuit, Figure 8-20 on page 14. It takes into
account the bias current as well as internal offset voltages of the amplifiers.
3.4
Pin 6: Supply and Power Dissipation
Power dissipation is shown in Figure 8-8 on page 9 to Figure 8-10 on page 10 for different loads.
Distortion characteristics are given in Figure 8-11 on page 10 to Figure 8-13 on page 11.
T jmax – T amb
P totmax = -------------------------------R thJA
where
Tjmax = Junction temperature = 140°C
Tamb = Ambient temperature
RthJA = Thermal resistance, junction-ambient
Power dissipated within the IC in a given application is found from the following equation:
Ptot = (VS × IS) + (IRMS × VS) – (RL × IRMS2)
IS is obtained from Figure 8-15 on page 12.
IRMS is the RMS current at the load RL.
The IC's operating range is defined by a peak operating load current of ±200 mA (Figure 8-8 on
page 9 to Figure 8-13 on page 11). It is further specified with respect to different loads (see Figure 8-14 on page 12). The left (ascending) portion of each of the three curves is defined by the
power level at which 10% distortion occurs. The center flat portion of each curve is defined by
the maximum output current capability of the integrated circuit. The right (descending) portion of
each curve is defined by the maximum internal power dissipation of the IC at 25°C. At higher
ambient temperatures, the maximum load power must be reduced according to the above mentioned equation.
4
U4083B
4655C–CORD–03/06
U4083B
3.5
Layout Considerations
Normally, a snubber is not needed at the output of the IC, unlike many other audio amplifiers.
However, the PC-board layout, stray capacitances, and the manner in which the speaker wires
are configured may dictate otherwise. Generally, the speaker wires should be twisted tightly,
and should not be more than a few cm (or inches) in length.
4. Absolute Maximum Ratings
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating
only and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of this
specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
Reference point pin 7, Tamb = 25° C unless otherwise specified.
Parameters
Symbol
Value
Unit
VS
–1.0 to +18
V
–1.0 to (VS + 1.0)
–1.0 to (VS + 1.0)
V
V
±250
mA
Tj
+140
°C
Storage temperature range
Tstg
–55 to +150
°C
Ambient temperature range
Tamb
–20 to +70
°C
Power dissipation SO8: Tamb = 60°C
Ptot
440
mW
Symbol
Value
Unit
RthJA
180
K/W
Symbol
Value
Unit
Supply voltage
Pin 6
Voltages
Disabled
Pins 1, 2, 3 and 4
Pins 5 and 8
Output current
Pins 5 and 8
Junction temperature
5. Thermal Resistance
Parameters
Junction ambient
SO8
6. Recommended Operating Conditions
Parameters
Supply voltage
Pin 6
VS
2 to 16
V
Load impedance
Pins 5 to 8
RL
8.0 to 100
Ω
IL
±200
mA
Differential gain (5.0 kHz bandwidth)
DG
0 to 46
dB
Voltage at CD
VCD
VS
V
Tamb
–20 to +70
°C
Load current
Ambient temperature range
Pin 1
5
4655C–CORD–03/06
7. Electrical Characteristics
Tamb = +25°C, reference point pin 7, unless otherwise specified
Parameters
Test Conditions
Symbol
Min.
GVOL1
80
GV2
–0.35
Typ.
Max.
Unit
Amplifiers (AC Characteristics)
Open-loop gain
(Amplifier 1, f < 100Hz)
Closed-loop gain (Amplifier 2)
VS = 6.0V, f = 1.0 kHz, RL = 32Ω
Gain bandwidth product
Output power
Total harmonic distortion
(f = 1.0 kHz)
VS = 6.0V, RL = 32Ω,
Po = 125 mW
VS > 3.0V, RL = 8Ω,
Po = 20 mW
VS > 12V, RL = 32Ω,
Po = 200 mW
Power supply rejection ratio
VS = 6.0V, ∆VS = 3.0V
C1 = α, C2 = 0.01 µF
C1 = 0.1 µF, C2 = 0, f = 1.0 kHz
C1 = 1.0 µF, C2 = 5.0 µF,
f = 1.0 kHz
VS = 6.0V, 1.0 kHz < f < 20 kHz,
CD = 2.0V
Muting
PO
PO
PO
0
+0.35
1.5
GBW
VS = 3.0V, RL = 16Ω, d < 10%
VS = 6.0V, RL = 32Ω, d < 10%
VS = 12V, RL = 100Ω, d < 10%
dB
dB
MHz
55
250
400
mW
d
0.5
d
0.5
d
0.6
PSRR
PSRR
12
1.0
%
dB
50
PSRR
52
GMUTE
>70
dB
Amplifiers (DC Characteristics)
1.15
2.65
5.65
Output DC level at VO1,
VO2
Rf = 75 kW
VS = 3.0V, RL = 16Ω
VS = 6.0V
VS = 12V
VO
VO
VO
Output high level
IO = –75 mA,
2.0V < VS < 16V
VOH
VS – 1
V
Output low level
IO = –75 mA,
2.0V < VS < 16V
VOL
0.16
V
Output DC offset voltage
(VO1 – VO2)
VS = 6.0V, Rf = 75 kΩ,
RL = 32Ω
∆VO
Input bias current at Vi
VS = 6.0V
–IIB
Equivalent resistance at Pin 3
VS = 6.0V
R
Equivalent resistance at Pin 2
VS = 6.0V
Chip disable Pin 1
Input voltage low
Input voltage high
Input resistance
Power supply current
6
VS = VCD = 16V
VS = 3.0V, RL = α, CD = 0.8V
VS = 16V, RL = α, CD = 0.8V
VS = 3.0V, RL = α, CD = 2.0V
1.0
V
0
+30
mV
100
200
nA
100
150
220
kΩ
R
18
25
40
kΩ
VIL
VIH
RCD
0.8
2.0
50
IS
IS
IS
–30
1.25
90
175
V
V
kΩ
65
4.0
5.0
100
mA
mA
µA
U4083B
4655C–CORD–03/06
U4083B
8. Typical Temperature Performance
Tamb = –20 to +70° C
Function
Typical Change
Units
±40
pA/° C
Total harmonic distortion
VS = 6.0V, RL = 32 Ω, Po = 125 mW, f = 1.0 kHz
+0.003
%/° C
Power supply current
VS = 3.0V, RL = α, CD = 0V
VS = 3.0V, RL = α, CD = 2.0V
–2.5
–0.03
µA/° C
µA/° C
Input bias current at Vi
Figure 8-1.
Turn-on Time versus C1 and C2 at Power On
360
300
C1 = 5 µF
ton (ms)
240
180
120
1 µF
60
VS switching from 0 to +6V
0
0
2
4
6
8
10
C2 (µF)
Amplifier 1 — Open-loop Gain and Phase
100
99.33
G (dB)
80
Phase
92.67
86.00
60
40
79.33
Phase (Degrees)
Figure 8-2.
Gain
20
72.67
0
0.1
1
10
100
66.00
1000
f (kHz)
7
4655C–CORD–03/06
Figure 8-3.
Differential Gain versus Frequency
40
Rf = 150 k
Differential gain (dB)
Ri = 6 k
32
Rf = 75 k
Ri = 3 k
24
Rf
Ci
Input
Ri
VO1
16
0.1 µF
Amp 1
8
Outputs
VO2
Amp 2
0
0
1
10
100
Frequency (kHz)
Figure 8-4.
Power Supply Rejection versus Frequency — C2 = 10 µF
60
60
C
C11 >
> 11 µF
µF
PSSR(dB)
(dB)
PSSR
50
50
C
C11 =
= 0.1
0.1 µF
µF
40
40
C2C= =
10µF
µF
2
30
30
C
C11 =
= 00
20
20
10
10
0.1
0.1
11
10
10
100
100
ff (kHz)
(kHz)
Figure 8-5.
Power Supply Rejection versus Frequency — C2 = 5 µF
60
C1 > 1 µF
PSRR (dB)
50
CC
1 = 0.1 µF
40
C2 = 5 µF
30
20
C1= 0
10
0.1
1
10
100
f (kHz)
8
U4083B
4655C–CORD–03/06
U4083B
Figure 8-6.
Power Supply Rejection versus Frequency — C2 = 1 µF
60
C1 > 5 µF
50
PSSR (dB)
C1 = 1 µF
40
C2 = 1 µF
C1 = 0.1 µF
30
20
C1 = 0
10
0.1
1
100
10
f (kHz)
Figure 8-7.
Power Supply Rejection versus Frequency — C2 = 0
55
C1 > 5 µF
PSSR (dB)
45
35
C1 = 1 µF
C2 = 0
25
C1 = 0.1 µF
15
5
0.1
1
100
10
f (kHz)
Figure 8-8.
Device Dissipation — RL = 8Ω
1200
VS = 12 V
1000
RL= 8 Ohm
Ptot (mW)
800
6V
600
400
3V
200
0
0
30
60
90
120
150
180
PL (mW)
9
4655C–CORD–03/06
Figure 8-9.
Device Dissipation — RL = 16Ω
1200
VS = 16 V
12 V
1000
RL = 16 Ohm
Ptot (mW)
800
600
6V
400
200
3V
0
0
100
200
400
300
PL (mW)
Figure 8-10. Device Dissipation — RL = 32Ω
1200
VS = 16 V
12 V
1000
Ptot (mW)
800
RL = 32 Ohm
600
400
6V
200
3V
0
0
100
200
300
400
500
600
PL (mW)
Figure 8-11. Distortion versus Power — f = 1 kHz, Delta – GV = 34 dB
10
8
VS = 3 V
VS = 3V
Delta-GV= 34 dB
RL = 8 Ohm
d(%)
6
f = 1 kHz
VS = 6 V
RL = 16 Ohm
RL = 32 Ohm
4
VS = 16V
2
RL = 32 Ohm
VS = 6 V
VS = 12 V
RL = 16 W
RL = 32 Ohm
0
0
100
200
300
400
PO (mW)
10
U4083B
4655C–CORD–03/06
U4083B
Figure 8-12. Distortion versus Power — f = 3 kHz, Delta – GV = 34 dB
10
8
VS = 3 V
RL = 16 Ohm
VS = 3 V
RL = 8 Ohm
f = 3 kHz
Delta-GV = 34 dB
VS= 6 V
RL = 32 Ohm
d(%)
6
4
VS = 6 V
RL = 16 Ohm
VS = 16 V
RL = 32 Ohm Limit
2
VS = 12 V
RL = 32 Ohm
0
0
100
200
300
400
PO (mW)
Figure 8-13. Distortion versus Power — f = 1 kHz or 3 kHz, Delta – GV = 12 dB
10
8
VS = 3 V
VS = 6 V
RL = 16 Ohm
VS = 3 V
f = 1 or 3 kHz
Delta-GV = 12 dB
RL = 8 Ohm
d(%)
6
RL = 32 W
4
2
VS = 16 V
VS = 6 V
RL = 16 Ohm Limit
VS = 12 V
RL = 32 Ohm
RL = 32 Ohm Limit
0
0
100
200
300
400
PO = ( mW )
11
4655C–CORD–03/06
Figure 8-14. Maximum Allowable Load Power
600
Tamb = 25°C - Derate at higher temperature
500
RL = 32
PL (W)
400
300
16 Ohm
200
8 Ohm
100
0
0
4
8
12
16
20
VS (V)
Figure 8-15. Power-supply Current
5
RL = ∞
4
IS (mA)
CD = 0
3
2
1
CD = V S
0
0
4
8
12
16
20
VS (V)
Input 1mV/Div
Output 20mV/Div
Figure 8-16. Small Signal Response
20 µs/Div
12
U4083B
4655C–CORD–03/06
U4083B
Input 80mV/Div
Output 1V/Div
Figure 8-17. Large Signal Response
20µs/Div
Figure 8-18. VS – VOH versus Load Current
1.3
VS-VOH(V )
1.2
1.1
1.0
2V< VS <16 V
0.9
0.8
0
40
80
120
200
160
IL (mA)
Figure 8-19. VOL versus Load Current
2.0
VOL (V)
1.6
1.2
VS = 2 V
0.8
VS= 3 V
0.4
VS>6 V
0
0
40
80
120
160
200
IL(mA)
13
4655C–CORD–03/06
Figure 8-20. Application Circuit
R1B
75k
Ci
Rf
6
Ri
Vi
3k
C1
1µF
VO1
4k
4k
50k
2
8
Amp2
125k
C1B
5
Amp1
3
FC3
C2
100nF
VS
4
0.1µF
10R
VO2
FC2
5µF
50k
C2B
100nF
U4083B
1
Bias circuit
CD
R2B
10R
7
GND
14
U4083B
4655C–CORD–03/06
U4083B
9. Ordering Information
Extended Type Number
Package
Remarks
U4083B-MFPY
SO8, Pb-free
Tube
U4083B-MFPG3Y
SO8, Pb-free
Taped and reeled
10. Package Information
Package SO8
Dimensions in mm
5.2
4.8
5.00
4.85
3.7
1.4
0.25
0.10
0.4
1.27
6.15
5.85
3.81
8
0.2
3.8
5
technical drawings
according to DIN
specifications
1
4
15
4655C–CORD–03/06
Atmel Corporation
2325 Orchard Parkway
San Jose, CA 95131, USA
Tel: 1(408) 441-0311
Fax: 1(408) 487-2600
Regional Headquarters
Europe
Atmel Sarl
Route des Arsenaux 41
Case Postale 80
CH-1705 Fribourg
Switzerland
Tel: (41) 26-426-5555
Fax: (41) 26-426-5500
Asia
Room 1219
Chinachem Golden Plaza
77 Mody Road Tsimshatsui
East Kowloon
Hong Kong
Tel: (852) 2721-9778
Fax: (852) 2722-1369
Japan
9F, Tonetsu Shinkawa Bldg.
1-24-8 Shinkawa
Chuo-ku, Tokyo 104-0033
Japan
Tel: (81) 3-3523-3551
Fax: (81) 3-3523-7581
Atmel Operations
Memory
2325 Orchard Parkway
San Jose, CA 95131, USA
Tel: 1(408) 441-0311
Fax: 1(408) 436-4314
RF/Automotive
Theresienstrasse 2
Postfach 3535
74025 Heilbronn, Germany
Tel: (49) 71-31-67-0
Fax: (49) 71-31-67-2340
Microcontrollers
2325 Orchard Parkway
San Jose, CA 95131, USA
Tel: 1(408) 441-0311
Fax: 1(408) 436-4314
La Chantrerie
BP 70602
44306 Nantes Cedex 3, France
Tel: (33) 2-40-18-18-18
Fax: (33) 2-40-18-19-60
ASIC/ASSP/Smart Cards
1150 East Cheyenne Mtn. Blvd.
Colorado Springs, CO 80906, USA
Tel: 1(719) 576-3300
Fax: 1(719) 540-1759
Biometrics/Imaging/Hi-Rel MPU/
High Speed Converters/RF Datacom
Avenue de Rochepleine
BP 123
38521 Saint-Egreve Cedex, France
Tel: (33) 4-76-58-30-00
Fax: (33) 4-76-58-34-80
Zone Industrielle
13106 Rousset Cedex, France
Tel: (33) 4-42-53-60-00
Fax: (33) 4-42-53-60-01
1150 East Cheyenne Mtn. Blvd.
Colorado Springs, CO 80906, USA
Tel: 1(719) 576-3300
Fax: 1(719) 540-1759
Scottish Enterprise Technology Park
Maxwell Building
East Kilbride G75 0QR, Scotland
Tel: (44) 1355-803-000
Fax: (44) 1355-242-743
Literature Requests
www.atmel.com/literature
Disclaimer: The information in this document is provided in connection with Atmel products. No license, express or implied, by estoppel or otherwise, to any
intellectual property right is granted by this document or in connection with the sale of Atmel products. EXCEPT AS SET FORTH IN ATMEL’S TERMS AND CONDITIONS OF SALE LOCATED ON ATMEL’S WEB SITE, ATMEL ASSUMES NO LIABILITY WHATSOEVER AND DISCLAIMS ANY EXPRESS, IMPLIED OR STATUTORY
WARRANTY RELATING TO ITS PRODUCTS INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
PURPOSE, OR NON-INFRINGEMENT. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT, CONSEQUENTIAL, PUNITIVE, SPECIAL OR INCIDENTAL DAMAGES (INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF PROFITS, BUSINESS INTERRUPTION, OR LOSS OF INFORMATION) ARISING OUT
OF THE USE OR INABILITY TO USE THIS DOCUMENT, EVEN IF ATMEL HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. Atmel makes no
representations or warranties with respect to the accuracy or completeness of the contents of this document and reserves the right to make changes to specifications
and product descriptions at any time without notice. Atmel does not make any commitment to update the information contained herein. Unless specifically provided
otherwise, Atmel products are not suitable for, and shall not be used in, automotive applications. Atmel’s products are not intended, authorized, or warranted for use
as components in applications intended to support or sustain life.
© Atmel Corporation 2006. All rights reserved. Atmel ®, logo and combinations thereof, Everywhere You Are ® and others, are registered trademarks or trademarks of Atmel Corporation or its subsidiaries. Other terms and product names may be trademarks of others.
Printed on recycled paper.
4655C–CORD–03/06