TS4871
OUTPUT RAIL TO RAIL
1W
AUDIO POWER AMPLIFIER
WITH STANDBY MODE
s
OPERATING FROM
V
CC
= 2.5V to 5.5V
s
1W
RAIL TO RAIL OUTPUT POWER @
Vcc=5V, THD=1%, f=1kHz, with
8
Ω
Load
MODE
(10nA)
PIN CONNECTIONS
(Top View)
TS4871IST - MiniSO8
1
2
3
4
8
7
6
5
s
ULTRA LOW CONSUMPTION IN STANDBY
Standby
Bypass
V
IN
+
V
IN-
V
OUT
2
GND
V
CC
V
OUT1
s
75dB
PSRR @ 217Hz from 5V to 2.6V
s
ULTRA LOW POP & CLICK
s
ULTRA LOW DISTORTION
(0.1%)
s
UNITY GAIN STABLE
s
AVAILABLE IN
SO8, MiniSO8 & DFN8 3x3mm
DESCRIPTION
TS4871ID-TS4871IDT - SO8
Standby
1
2
3
4
8
7
6
5
V
OUT
2
GND
V
CC
V
OUT1
The TS4871 is an Audio Power Amplifier capable
of delivering 1W of continuous RMS Ouput Power
into 8
Ω
load @ 5V.
This Audio Amplifier is exhibiting 0.1% distortion
level (THD) from a 5V supply for a Pout = 250mW
RMS. An external standby mode control reduces
the supply current to less than 10nA. An internal
thermal shutdown protection is also provided.
The TS4871 has been designed for high quality
audio applications such as mobile phones and to
minimize the number of external components.
The unity-gain stable amplifier can be configured
by external gain setting resistors.
APPLICATIONS
Bypass
V
IN
+
V
IN-
TS4871IQT - DFN8
STANDBY
BYPASS
V
IN+
V
IN-
1
2
3
4
8
7
6
5
V
OUT 2
GND
Vcc
V
OUT 1
s
Mobile Phones (Cellular / Cordless)
s
Laptop / Notebook Computers
s
PDAs
s
Portable Audio Devices
ORDER CODE
Part
Number
TS4871
Temperature
Range: I
-40, +85°C
Package
Marking
D
•
•
•
S
Q
4871I
4871
Vcc
TYPICAL APPLICATION SCHEMATIC
Cfeed
Rfeed
Vcc
6
Audio
Input
Cin
Vcc
Cs
Rin
4
3
Vin-
Vin+
-
+
Vout1 5
RL
8 Ohms
-
Av=-1
+
Vout2
8
2
Rstb
1
Bypass
Standby
Bias
GND
TS4871
Cb
7
MiniSO & DFN
only available in Tape & Reel with T suffix(IST & IQT)
D =
Small Outline Package (SO) - also available in Tape & Reel (DT)
June 2003
1/28
TS4871
ABSOLUTE MAXIMUM RATINGS
Symbol
V
CC
V
i
T
oper
T
stg
T
j
R
thja
Supply voltage
1)
Input Voltage
2)
Operating Free Air Temperature Range
Storage Temperature
Maximum Junction Temperature
Thermal Resistance Junction to Ambient
3)
SO8
MiniSO8
QNF8
Power Dissipation
Parameter
Value
6
G
ND
to V
CC
-40 to + 85
-65 to +150
150
175
215
70
Internally Limited
4)
2
200
Class A
260
Unit
V
V
°C
°C
°C
°C/W
Pd
ESD
Human Body Model
ESD
Machine Model
Latch-up Latch-up Immunity
Lead Temperature (soldering, 10sec)
1.
2.
3.
4.
All voltages values are measured with respect to the ground pin.
The magnitude of input signal must never exceed V
CC
+ 0.3V / G
ND
- 0.3V
Device is protected in case of over temperature by a thermal shutdown active @ 150°C.
Exceeding the power derating curves during a long period, involves abnormal operating condition.
kV
V
°C
OPERATING CONDITIONS
Symbol
V
CC
V
ICM
V
STB
R
L
R
thja
Supply Voltage
Common Mode Input Voltage Range
Standby Voltage Input :
Device ON
Device OFF
Load Resistor
Thermal Resistance Junction to Ambient
1)
SO8
MiniSO8
DFN8
2)
Parameter
Value
2.5 to 5.5
G
ND
to V
CC
- 1.2V
G
ND
≤
V
STB
≤
0.5V
V
CC
- 0.5V
≤
V
STB
≤
V
CC
4 - 32
150
190
41
Unit
V
V
V
Ω
°C/W
1. This thermal resistance can be reduced with a suitable PCB layout (see Power Derating Curves Fig. 20)
2. When mounted on a 4 layers PCB
2/28
TS4871
ELECTRICAL CHARACTERISTICS
V
CC
=
+5V,
GND =
0V,
T
amb
= 25°C (unless otherwise specified)
Symbol
I
CC
I
STANDBY
Voo
Po
THD + N
PSRR
Φ
M
GM
GBP
Parameter
Supply Current
No input signal, no load
Standby Current
1)
No input signal, Vstdby = Vcc, RL = 8Ω
Output Offset Voltage
No input signal, RL = 8Ω
Output Power
THD = 1% Max, f = 1kHz, RL = 8Ω
Total Harmonic Distortion + Noise
Po = 250mW rms, Gv = 2, 20Hz < f < 20kHz, RL = 8Ω
Power Supply Rejection Ratio
2)
f = 217Hz, RL = 8Ω, RFeed = 22KΩ, Vripple = 200mV rms
Phase Margin at Unity Gain
R
L
= 8Ω, C
L
= 500pF
Gain Margin
R
L
= 8Ω, C
L
= 500pF
Gain Bandwidth Product
R
L
= 8Ω
Min.
Typ.
6
10
5
1
0.15
75
70
20
2
Max.
8
1000
20
Unit
mA
nA
mV
W
%
dB
Degrees
dB
MHz
1. Standby mode is actived when Vstdby is tied to Vcc
2. Dynamic measurements - 20*log(rms(Vout)/rms(Vripple)). Vripple is the surimposed sinus signal to Vcc @ f = 217Hz
V
CC
=
+3.3V,
GND =
0V,
T
amb
= 25°C (unless otherwise specified)
3)
Symbol
I
CC
I
STANDBY
Voo
Po
THD + N
PSRR
Φ
M
GM
GBP
Parameter
Supply Current
No input signal, no load
Standby Current
1)
No input signal, Vstdby = Vcc, RL = 8Ω
Output Offset Voltage
No input signal, RL = 8Ω
Output Power
THD = 1% Max, f = 1kHz, RL = 8Ω
Total Harmonic Distortion + Noise
Po = 250mW rms, Gv = 2, 20Hz < f < 20kHz, RL = 8Ω
Power Supply Rejection Ratio
2)
f = 217Hz, RL = 8Ω, RFeed = 22KΩ, Vripple = 200mV rms
Phase Margin at Unity Gain
R
L
= 8Ω, C
L
= 500pF
Gain Margin
R
L
= 8Ω, C
L
= 500pF
Gain Bandwidth Product
R
L
= 8Ω
Min.
Typ.
5.5
10
5
450
0.15
75
70
20
2
Max.
8
1000
20
Unit
mA
nA
mV
mW
%
dB
Degrees
dB
MHz
1. Standby mode is actived when Vstdby is tied to Vcc
2. Dynamic measurements - 20*log(rms(Vout)/rms(Vripple)). Vripple is the surimposed sinus signal to Vcc @ f = 217Hz
3. All electrical values are made by correlation between 2.6V and 5V measurements
3/28
TS4871
ELECTRICAL CHARACTERISTICS
V
CC
=
2.6V,
GND =
0V,
T
amb
= 25°C (unless otherwise specified)
Symbol
I
CC
I
STANDBY
Voo
Po
THD + N
PSRR
Φ
M
GM
GBP
Parameter
Supply Current
No input signal, no load
Standby Current
1)
No input signal, Vstdby = Vcc, RL = 8Ω
Output Offset Voltage
No input signal, RL = 8Ω
Output Power
THD = 1% Max, f = 1kHz, RL = 8Ω
Total Harmonic Distortion + Noise
Po = 200mW rms, Gv = 2, 20Hz < f < 20kHz, RL = 8Ω
Power Supply Rejection Ratio
2)
f = 217Hz, RL = 8Ω, RFeed = 22KΩ, Vripple = 200mV rms
Phase Margin at Unity Gain
R
L
= 8Ω, C
L
= 500pF
Gain Margin
R
L
= 8Ω, C
L
= 500pF
Gain Bandwidth Product
R
L
= 8Ω
Min.
Typ.
5.5
10
5
260
0.15
75
70
20
2
Max.
8
1000
20
Unit
mA
nA
mV
mW
%
dB
Degrees
dB
MHz
1. Standby mode is actived when Vstdby is tied to Vcc
2. Dynamic measurements - 20*log(rms(Vout)/rms(Vripple)). Vripple is the surimposed sinus signal to Vcc @ f = 217Hz
Components
Rin
Cin
Rfeed
Cs
Cb
Cfeed
Rstb
Gv
Functional Description
Inverting input resistor which sets the closed loop gain in conjunction with Rfeed. This resistor also
forms a high pass filter with Cin (fc = 1 / (2 x Pi x Rin x Cin))
Input coupling capacitor which blocks the DC voltage at the amplifier input terminal
Feed back resistor which sets the closed loop gain in conjunction with Rin
Supply Bypass capacitor which provides power supply filtering
Bypass pin capacitor which provides half supply filtering
Low pass filter capacitor allowing to cut the high frequency
(low pass filter cut-off frequency 1 / (2 x Pi x Rfeed x Cfeed))
Pull-up resistor which fixes the right supply level on the standby pin
Closed loop gain in BTL configuration = 2 x (Rfeed / Rin)
REMARKS
1.
All measurements, except PSRR measurements, are made with a supply bypass capacitor Cs = 100µF.
2.
External resistors are not needed for having better stability when supply @ Vcc down to 3V. By the way,
the quiescent current remains the same.
3.
The standby response time is about 1µs.
4/28
TS4871
Fig. 1 : Open Loop Frequency Response
Fig. 2 : Open Loop Frequency Response
0
60
Gain
Vcc = 5V
RL = 8
Ω
Tamb = 25
°
C
-20
-40
-60
Phase (Deg)
0
60
Gain
Vcc = 5V
ZL = 8
Ω
+ 560pF
Tamb = 25
°
C
-20
-40
-60
Phase (Deg)
40
Gain (dB)
40
Phase
Gain (dB)
Phase
20
-80
-100
-120
-80
-100
-120
20
0
-140
-160
0
-140
-160
-20
-180
-200
-20
-180
-200
-40
0.3
1
10
100
Frequency (kHz)
1000
10000
-220
-40
0.3
1
10
100
1000
Frequency (kHz)
10000
-220
Fig. 3 : Open Loop Frequency Response
Fig. 4 : Open Loop Frequency Response
80
60
40
Gain
Vcc = 3.3V
RL = 8
Ω
Tamb = 25
°
C
0
-20
-40
-60
-80
80
60
40
Phase
20
0
-20
-40
0.3
Gain
Vcc = 3.3V
ZL = 8
Ω
+ 560pF
Tamb = 25
°
C
0
-20
-40
-60
-80
-100
-120
-140
-160
-180
-200
-220
1
10
100
1000
Frequency (kHz)
10000
-240
Phase (Deg)
Phase (Deg)
Phase
20
0
-100
-120
-140
-160
-180
-200
-220
-240
-20
-40
0.3
1
10
100
1000
Frequency (kHz)
10000
Fig. 5 : Open Loop Frequency Response
Phase (Deg)
Gain (dB)
Fig. 6 : Open Loop Frequency Response
Gain (dB)
80
60
40
Gain (dB)
0
Gain
Vcc = 2.6V
RL = 8
Ω
Tamb = 25
°
C
-20
-40
-60
-80
Phase
Phase (Deg)
Gain (dB)
80
Gain
60
40
Phase
20
0
-20
-40
0.3
Vcc = 2.6V
ZL = 8
Ω
+ 560pF
Tamb = 25
°
C
0
-20
-40
-60
-80
-100
-120
-140
-160
-180
-200
-220
1
10
100
1000
Frequency (kHz)
10000
-240
-100
-120
-140
-160
-180
-200
-220
-240
20
0
-20
-40
0.3
1
10
100
1000
Frequency (kHz)
10000
5/28