ST TS4902 User Manual

s

TS4902

300mW at 3.3V SUPPLY AUDIO POWER AMPLIFIER

WITH STANDBY MODE ACTIVE LOW

■OPERATING FROM V

= 2.2V to 5.5V

CC

■0.7W OUTPUT POWER @ Vcc=5V, THD=1%,

f=1kHz, with an 8

Ω load

■0.3W OUTPUT POWER @ Vcc=3.3V,

THD=1%, f=1kHz, with an 8

Ω load

■ULTRA LOW CONSUMPTION IN STANDBY

MODE (10nA)

■77dB PSRR @ 217Hz from 5V to 2.2V

■ULTRA LOW POP & CLICK

■ULTRA LOW DISTORTION (0.1%)

■UNITY GAIN STABLE

■AVAILABLE IN MiniSO8 & SO8

DESCRIPTION

The TS4902 is an audio power amplifier designed to provide the best pri ce to power ratio while preserving high audio quality.

Available in MiniSO8 & SO8 package, it is capable of delivering up to 0.7W of continuous RMS ouput power into an 8

TS4902 is also exhibiting an outstanding 0.1% distortion level (THD) from a 5V supply for a Pout of 200mW RMS.

Ω load @ 5V.

PIN CONNECTIONS (top view)

TS4902IS-TS4902IST - MiniSO8

Standby

Bypass

V+

VIN-

Standby

Bypass

V+

IN

VIN-

1 2 3

IN

4

TS4902ID-TS4902IDT - SO8

1

2 3 4

8

V2OUT

7

GND

6

CC

V

5

VOUT1

8

V2OUT

7

GND

6

CC

V

5

VOUT1

An externally controlled standby mode reduces the supply current to less than 10nA. It also includes an internal thermal shutdown protection.

The unity-gain stable amplifier can be configured by external gain setting resistors.

APPLICATIONS

■Mobile Phones (Cellular / Cordless)

■PDAs

■Portable Audio Devices

ORDER CODE

Part Number

TS4902IST

TS4902ID

S = MiniSO Package (MiniSO) is only available in Tape & Reel (ST) D = Small Outline Package (SO) - also available in Tape & Reel (DT)

Temperature

Range

-40, +85°C

January 2002

Package

ST D

•

TYPICAL APPLICATION SCHEMATIC

Audio Input

Cin

VCC

Rstb

Rin

Cfeed

Rfeed

VCC 6

Vin-

4

Vin+

3

Bypass

2

Standby

1

Cb

V

-

C

+

-

Bias

AV = -1

+

GND

7

Cs

Vout 1

5

RL 8 Ohm

Vout 2

8

TS4902

1/19

TS4902

ABSOLUTE MAXIMUM RATINGS

Symbol Parameter Value Unit

V

T

R

Supply voltage

CC

V

Input Voltage

i

Operating Free Air Temperature Range -40 to + 85 °C

oper

Storage Temperature -65 to +150 °C

stg

T

Maximum Junction Temperature 150 °C

j

Thermal Resistance Junction to Ambient

thja

SO8 MiniSO8

Pd

Power Dissipation

ESD Human Body Model 2 kV ESD Machine Model 200 V

Latch-up Latch-up Immunity Class A

Lead Temperature (soldering, 10sec ) 250 °C

1. All voltages values are measured with respect to the ground pin.

2. The magnitude of input signal must never exceed V

3. Device is protected in case of over temperature by a thermal shutdown active @ 150°C.

4. Exceeding the power derating curves during a long period, will cause abnormal operation.

1)

2)

3)

6V

GND to V

CC

175 215

4)

+ 0.3V / GND - 0.3V

CC

See the power derating

curves Fig 20.

V

°C/W

OPERATING CONDITIONS

Symbol Parameter Value Unit

V

R

1. This thermal resistance can be reduced with a suitable PCB layout (see Power Derating Curves)

Supply Voltage 2.2 to 5.5 V

CC

to VCC - 1.5V

Common Mode Input Voltage Range

ICM

Standby Voltage Input :

STB

Device ON Device OFF

R

Load Resistor 4 - 32

L

Thermal Resistance Junction to Ambient

thja

1)

SO8 MiniSO8

G

ND

1.5 ≤ V

GND ≤ V

STB

150 190

≤ V

STB

CC

≤ 0.5

V

Ω

°C/W

2/19

TS4902

ELECTRICAL CHARACTERISTICS

= +5V, GND = 0V , T

V

CC

Symbol Parameter Min. Typ. Max. Unit

= 25°C (unless otherwise specified)

amb

I

CC

I

STANDBY

Voo

Po

THD + N

PSRR

Φ

GM

GBP

1. Standby mode is actived wh en Vstdby is tied to GND

2. Dynamic measurements - 20*log(r m s(Vout)/rms(Vripple)). Vripple is the surim posed sinus signal to Vc c @ f = 217Hz

= +3.3V, GND = 0V, T

V

CC

Supply Current

No input signal, no load

Standby Current

1)

No input signal, Vstdby = GND, RL = 8

Output Offset Voltage

No input signal, RL = 8

Output Power

THD = 1% Max, f = 1kHz, RL = 8

Total Harmonic Distortion + Noise

Po = 250mW rms, Gv = 2, 20Hz < f < 20kHz, RL = 8

Power Supply Rejection Ratio

f = 217Hz, RL = 8

Phase Margin at Unity Gain

M

R

= 8Ω, CL = 500pF

L

Gain Margin R

= 8Ω, CL = 500pF

L

Gain Bandwidth Product R

= 8

Ω

L

amb

Ω

2)

RFeed = 22K

Ω,

Vripple = 200mV rms

Ω,

= 25°C (unless otherwise specified)3)

68mA

10 1000 nA

520mV

0.7 W

0.15 %

77 dB

70 Degrees

20 dB

2MHz

Symbol Parameter Min. Typ. Max. Unit

I

CC

I

STANDBY

Voo

Po

THD + N

PSRR

Φ

GM

GBP

1. Standby mode is actived wh en Vstdby is tied to GND

2. Dynamic measurements - 20*log(r m s(Vout)/rms(Vripple)). Vripple is the surim posed sinus signal to Vc c @ f = 217Hz

3. All electrical values are made by correlation between 2.6V and 5V measurement s

Supply Current

No input signal, no load

Standby Current

1)

No input signal, Vstdby = GND, RL = 8

Output Offset Voltage

No input signal, RL = 8

Output Power

THD = 1% Max, f = 1kHz, RL = 8

Total Harmonic Distortion + Noise

Po = 250mW rms, Gv = 2, 20Hz < f < 20kHz, RL = 8

Power Supply Rejection Ratio

f = 217Hz, RL = 8

Phase Margin at Unity Gain

M

R

= 8Ω, CL = 500pF

L

Gain Margin R

= 8Ω, CL = 500pF

L

Gain Bandwidth Product R

= 8

Ω

L

Ω

2)

RFeed = 22K

Ω,

Ω

Vripple = 200mV rms

Ω,

5.5 8 mA

10 1000 nA

520mV

300 mW

Ω

0.15 %

77 dB

70 Degrees

20 dB

2MHz

3/19

TS4902

ELECTRICAL CHARACTERISTICS

V

= 2.6V, GND = 0V, T

CC

Symbol Parameter Min. Typ. Max. Unit

= 25°C (unless otherwise specified)

amb

I

CC

I

STANDBY

Voo

Po

THD + N

PSRR

Φ

GM

GBP

1. Standby mode is actived wh en Vstdby is tied to GND

2. Dynamic measurements - 20*log(r m s(Vout)/rms(Vripple)). Vripple is the surim posed sinus signal to Vc c @ f = 217Hz

Supply Current

No input signal, no load

Standby Current

1)

No input signal, Vstdby = GND, RL = 8

Output Offset Voltage

No input signal, RL = 8

Output Power

THD = 1% Max, f = 1kHz, RL = 8

Total Harmonic Distortion + Noise

Po = 200mW rms, Gv = 2, 20Hz < f < 20kHz, RL = 8

Power Supply Rejection Ratio

f = 217Hz, RL = 8

Phase Margin at Unity Gain

M

R

= 8Ω, CL = 500pF

L

Gain Margin R

= 8Ω, CL = 500pF

L

Gain Bandwidth Product R

= 8

Ω

L

Ω

2)

RFeed = 22K

Ω,

Ω

Vripple = 200mV rms

Ω,

5.5 8 mA

10 1000 nA

520mV

180 mW

Ω

0.15 %

77 dB

70 Degrees

20 dB

2MHz

Components Functional Description

Rin

Cin

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

Rfeed Feed back resistor which sets the closed loop gain in conjunction with Rin

Cs Supply Bypass capacitor which provides power supply filtering

Cb Bypass pin capacitor which provides half supply filtering

Cfeed

Low pass filter capacitor allowing to cut the high frequency (low pass filter cut-off frequency 1 / (2 x Pi x Rfeed x Cfeed))

Rstb Pull-up resistor which fixes the right supply level on the standby pin

Gv 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. The standby response time is about 1µs.

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TS4902

0.3 1 10 100 1000 10000

-40

-20

0

20

40

60

80

-240

-220

-200

-180

-160

-140

-120

-100

-80

-60

-40

-20

0

Gain (dB)

Frequency (kHz)

Vcc = 3.3V ZL = 8Ω + 560pF Tamb = 25°C

Gain

Phase

Phase (Deg)

0.3 1 10 100 1000 10000

-40

-20

0

20

40

60

80

-240

-220

-200

-180

-160

-140

-120

-100

-80

-60

-40

-20

0

Gain (dB)

Frequency (kHz)

Vcc = 2.6V ZL = 8Ω + 560pF Tamb = 25°C

Gain

Phase

Phase (Deg)

Fig. 1 : Open Loop Frequency Response

0

60

40

Phase

20

Gain (dB)

0

-20

-40

0.3 1 10 100 1000 10000

Gain

Frequency (kHz)

Vcc = 5V RL = 8 Tamb = 25°C

Ω

-20

-40

-60

-80

-100

-120

-140

-160

-180

-200

-220

Fig. 3 : Open Loop Frequency Response

80

60

40

20

Gain (dB)

0

-20

-40

0.3 1 10 100 1000 10000

Gain

Phase

Frequency (kHz)

Vcc = 33V RL = 8

Ω

Tamb = 25°C

0

-20

-40

-60

-80

-100

-120

-140

-160

-180

-200

-220

-240

Phase (Deg)

Fig. 2 : Open Loop Frequency Response

0

60

40

Phase

20

Gain (dB)

0

-20

-40

0.3 1 10 100 1000 10000

Gain

Frequency (kHz)

Vcc = 5V ZL = 8Ω + 560pF Tamb = 25°C

-20

-40

-60

-80

-100

-120

-140

-160

-180

-200

-220

Fig. 4 : Open Loop Frequency Response

Phase (Deg)

Fig. 5 : Open Loop Frequency Response

80

60

40

20

Gain (dB)

0

-20

-40

0.3 1 10 100 1000 10000

Gain

Phase

Frequency (kHz)

Vcc = 2.6V RL = 8 Tamb = 25°C

Fig. 6 : Open Loop Frequency Response

0

-20

Ω

-40

-60

-80

-100

-120

-140

-160

-180

-200

-220

-240

Phase (Deg)

5/19

TS4902

0.3 1 10 100 1000 10000

-40

-20

0

20

40

60

80

100

-240

-220

-200

-180

-160

-140

-120

-100

-80

Gain (dB)

Frequency (kHz)

Vcc = 3.3V CL = 560pF Tamb = 25°C

Gain

Phase

Phase (Deg)

Fig. 7 : Open Loop Frequency Response

100

80

60

Gain

40

20

Gain (dB)

0

Vcc = 5V CL = 560pF

-20

Tamb = 25°C

-40

0.3 1 10 100 1000 10000

Phase

Frequency (kHz)

-80

-100

-120

-140

-160

-180

-200

-220

Fig. 9 : Open Loop Frequency Response

100

80

60

Gain

40

20

Gain (dB)

0

Vcc = 2.6V

-20

CL = 560pF Tamb = 25°C

-40

0.3 1 10 100 1000 10000

Phase

Frequency (kHz)

-80

-100

-120

-140

-160

-180

-200

-220

-240

Fig. 8 : Open Loop Frequency Response

Phase (Deg)

6/19