Datasheet

ManualsBrandsSTMICROELECTRONICS ManualsLinear ICsLinear IC - Audio amplifier 1-channel (mono) Class AB SO 8

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■ OPERATING FROM V

= 2.5V to 5.5V

■ 1W RAIL TO RAIL OUTPUT POWER @

Vcc=5V, THD=1%, f=1kHz, with 8

Ω Load

■ ULTRA LOW CONSUMPTION IN STANDBY

MODE (10nA)

■ 75dB PSRR @ 217Hz from 5V to 2.6V

■ ULTRA LOW POP & CLICK

■ ULTRA LOW DISTORTION (0.1%)

■ UNITY GAIN STABLE

■ AVAILABLE IN SO8, MiniSO8 & DFN8 3x3mm

DESCRIPTION

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

■ Mobile Phones (Cellular / Cordless)

■ Laptop / Notebook Computers

■ PDAs

■ Portable Audio Devices

ORDER CODE

MiniSO & DFN only available in Tape & Reel with T suffix(IST & IQT)

D = Small Outline Package (SO) - also available in Tape & Reel (DT)

PIN CONNECTIONS (Top View)

Part

Number

Temperature

Range: I

Package

Marking

DSQ

TS4871 -40, +85°C

•

4871I

••

4871

Standby

Bypass

V+

VIN-

V2OUT

GND

VOUT1

Rin

Cin

Rstb

Rfeed

Vin-

Vin+

Bypass

Standby

Bias

Vout1

Vout2

Av=-1

TS4871

8 Ohms

Vcc

GND

Audio

Input

Vcc

Cfeed

TYPICAL APPLICATION SCHEMATIC

TS4871IST - MiniSO8

TS4871ID-TS4871IDT - SO8

Standby

Bypass

V+

VIN-

V2OUT

GND

VOUT1

STANDBY

BYPASS

OUT 2

IN-

IN+

Vcc

OUT 1

GND

STANDBY

BYPASS

OUT 2

IN-

IN+

Vcc

OUT 1

GND

TS4871IQT - DFN8

TS4871

OUTPUT RAIL TO RAIL 1W AUDIO POWER AMPLIFIER

WITH STANDBY MODE

June 2003

Summary of content (28 pages)

PAGE 1
TS4871 OUTPUT RAIL TO RAIL 1W AUDIO POWER AMPLIFIER WITH STANDBY MODE ■ OPERATING FROM VCC = 2.5V to 5.5V PIN CONNECTIONS (Top View) ■ 1W RAIL TO RAIL OUTPUT POWER @ Vcc=5V, THD=1%, f=1kHz, with 8Ω Load TS4871IST - MiniSO8 ■ ULTRA LOW CONSUMPTION IN STANDBY MODE (10nA) Standby 1 8 VOUT2 Bypass 2 7 GND VIN+ 3 6 VCC VIN- 4 5 VOUT1 ■ 75dB PSRR @ 217Hz from 5V to 2.6V ■ ULTRA LOW POP & CLICK ■ ULTRA LOW DISTORTION (0.
PAGE 2
TS4871 ABSOLUTE MAXIMUM RATINGS Symbol VCC Vi Parameter Supply voltage 1) 2) Unit 6 V GND to VCC V Toper Operating Free Air Temperature Range -40 to + 85 °C Tstg Storage Temperature Tj Rthja Pd Input Voltage -65 to +150 °C Maximum Junction Temperature 150 °C Thermal Resistance Junction to Ambient 3) SO8 MiniSO8 QNF8 175 215 70 Internally Limited4) 2 200 Class A 260 Power Dissipation ESD Human Body Model ESD Machine Model Latch-up Latch-up Immunity Lead Temperature (soldering, 10sec
PAGE 3
TS4871 ELECTRICAL CHARACTERISTICS VCC = +5V, GND = 0V, Tamb = 25°C (unless otherwise specified) Symbol Typ. Max. Unit Supply Current No input signal, no load 6 8 mA Standby Current 1) No input signal, Vstdby = Vcc, RL = 8Ω 10 1000 nA Voo Output Offset Voltage No input signal, RL = 8Ω 5 20 mV Po Output Power THD = 1% Max, f = 1kHz, RL = 8Ω 1 W 0.
PAGE 4
TS4871 ELECTRICAL CHARACTERISTICS VCC = 2.6V, GND = 0V, Tamb = 25°C (unless otherwise specified) Symbol Typ. Max. Unit Supply Current No input signal, no load 5.5 8 mA Standby Current 1) No input signal, Vstdby = Vcc, RL = 8Ω 10 1000 nA Voo Output Offset Voltage No input signal, RL = 8Ω 5 20 mV Po Output Power THD = 1% Max, f = 1kHz, RL = 8Ω 260 mW Total Harmonic Distortion + Noise Po = 200mW rms, Gv = 2, 20Hz < f < 20kHz, RL = 8Ω 0.
PAGE 5
TS4871 Fig. 1 : Open Loop Frequency Response Fig. 2 : Open Loop Frequency Response 0 -60 40 -80 -100 -120 -140 -60 -80 Phase -100 20 -120 -140 0 -160 -160 -180 -20 -180 -20 -200 -40 0.3 1 10 100 1000 -200 -220 10000 -40 0.3 1 10 Frequency (kHz) Fig. 3 : Open Loop Frequency Response 60 Vcc = 3.3V RL = 8Ω Tamb = 25°C -60 -100 -120 20 -140 -160 0 Phase (Deg) Gain (dB) Phase Gain 60 -40 -80 40 0 80 -20 Gain (dB) Gain Vcc = 3.
PAGE 6
TS4871 Phase 60 100 -100 80 -120 60 Gain (dB) Gain -140 40 -160 20 0 -20 -40 0.3 -180 1 10 100 -40 0.3 -80 80 -100 Phase Gain (dB) Gain -140 40 -160 20 -180 0 -40 0.3 6/28 -200 Vcc = 2.6V CL = 560pF Tamb = 25°C 1 10 -220 100 1000 Frequency (kHz) 10000 -240 Phase (Deg) -120 60 -20 -180 -220 Fig.
PAGE 7
TS4871 Fig. 10 : Power Supply Rejection Ratio (PSRR) vs Power supply Fig. 11 : Power Supply Rejection Ratio (PSRR) vs Feedback Capacitor -30 -10 Vripple = 200mVrms Rfeed = 22Ω Input = floating RL = 8Ω Tamb = 25°C -50 -20 -30 PSRR (dB) PSRR (dB) -40 Vcc = 5V, 3.3V & 2.6V Cb = 1µF & 0.1µF -60 -40 Vcc = 5, 3.3 & 2.6V Cb = 1µF & 0.
PAGE 8
TS4871 Fig. 16 : Pout @ THD + N = 10% vs Supply Voltage vs RL Fig. 15 : Pout @ THD + N = 1% vs Supply Voltage vs RL 2.0 8Ω Gv = 2 & 10 Cb = 1µF F = 1kHz BW < 125kHz Tamb = 25°C 1.2 1.0 Output power @ 10% THD + N (W) Output power @ 1% THD + N (W) 1.4 6Ω 4Ω 0.8 16Ω 0.6 0.4 0.2 32Ω 0.0 2.5 3.0 3.5 4.0 4.5 Gv = 2 & 10 Cb = 1µF F = 1kHz BW < 125kHz Tamb = 25°C 1.8 1.6 1.4 4Ω 1.2 1.0 16Ω 0.8 0.6 0.4 0.2 32Ω 0.0 2.5 5.0 8Ω 3.0 3.5 4.5 5.0 Fig. 18 : Power Dissipation vs Pout 1.4 0.
PAGE 9
TS4871 Fig. 21 : THD + N vs Output Power Fig. 22 : THD + N vs Output Power 10 10 RL = 4Ω, Vcc = 5V Gv = 10 Cb = Cin = 1µF BW < 125kHz, Tamb = 25°C THD + N (%) THD + N (%) Rl = 4Ω Vcc = 5V Gv = 2 Cb = Cin = 1µF BW < 125kHz Tamb = 25°C 1 20kHz 20kHz 1 20Hz 1kHz 20Hz, 1kHz 0.1 1E-3 0.01 0.1 Output Power (W) 0.1 1E-3 1 Fig. 23 : THD + N vs Output Power 1 Fig. 24 : THD + N vs Output Power 10 10 RL = 4Ω, Vcc = 3.3V Gv = 2 Cb = Cin = 1µF BW < 125kHz Tamb = 25°C THD + N (%) THD + N (%) 0.01 0.
PAGE 10
TS4871 Fig. 27 : THD + N vs Output Power Fig. 28 : THD + N vs Output Power 10 RL = 8Ω Vcc = 5V Gv = 2 Cb = Cin = 1µF BW < 125kHz Tamb = 25°C 1 20Hz, 1kHz THD + N (%) THD + N (%) 10 20kHz 0.1 RL = 8Ω Vcc = 5V Gv = 10 Cb = Cin = 1µF BW < 125kHz Tamb = 25°C 1 20Hz 20kHz 0.1 1kHz 1E-3 0.01 0.1 Output Power (W) 1 1E-3 Fig. 29 : THD + N vs Output Power 1 Fig. 30 : THD + N vs Output Power 10 10 RL = 8Ω, Vcc = 3.3V Gv = 2 Cb = Cin = 1µF BW < 125kHz Tamb = 25°C THD + N (%) THD + N (%) 0.
PAGE 11
TS4871 Fig. 33 : THD + N vs Output Power Fig. 34 : THD + N vs Output Power 10 RL = 8Ω Vcc = 5V Gv = 2 Cb = 0.1µF, Cin = 1µF BW < 125kHz Tamb = 25°C 1 RL = 8Ω, Vcc = 5V, Gv = 10 Cb = 0.1µF, Cin = 1µF BW < 125kHz, Tamb = 25°C 20Hz THD + N (%) THD + N (%) 10 20Hz 20kHz 1kHz 1 20kHz 1kHz 0.1 0.1 1E-3 0.01 0.1 Output Power (W) 1 1E-3 Fig. 35 : THD + N vs Output Power 10 RL = 8Ω, Vcc = 3.3V Gv = 2 Cb = 0.1µF, Cin = 1µF BW < 125kHz Tamb = 25°C THD + N (%) RL = 8Ω, Vcc = 3.3V, Gv = 10 Cb = 0.
PAGE 12
TS4871 Fig. 39 : THD + N vs Output Power Fig. 40 : THD + N vs Output Power 10 10 20kHz RL = 16Ω, Vcc = 5V Gv = 10 Cb = Cin = 1µF BW < 125kHz Tamb = 25°C 1 THD + N (%) THD + N (%) 1 RL = 16Ω, Vcc = 5V Gv = 2 Cb = Cin = 1µF BW < 125kHz Tamb = 25°C 20kHz 0.1 0.1 1kHz 20Hz, 1kHz 0.01 1E-3 0.01 0.1 Output Power (W) 1 Fig. 41 : THD + N vs Output Power 0.01 1E-3 20kHz 0.1 1 RL = 16Ω Vcc = 3.3V Gv = 10 Cb = Cin = 1µF BW < 125kHz Tamb = 25°C 20kHz 0.1 1kHz 20Hz 20Hz, 1kHz 0.01 1E-3 0.
PAGE 13
TS4871 Fig. 45 : THD + N vs Frequency Pout = 1.2W RL = 4Ω, Vcc = 5V Gv = 2 Cb = 1µF BW < 125kHz Tamb = 25°C 1 THD + N (%) THD + N (%) 1 Fig. 46 : THD + N vs Frequency Pout = 1.2W RL = 4Ω, Vcc = 5V Gv = 10 Cb = 1µF BW < 125kHz Tamb = 25°C Pout = 600mW 0.1 20 100 1000 Frequency (Hz) 0.01 20 10000 Pout = 600mW 0.1 100 1000 Frequency (Hz) Fig. 47 : THD + N vs Frequency Fig. 48 : THD + N vs Frequency RL = 4Ω, Vcc = 3.3V Gv = 2 Cb = 1µF BW < 125kHz Tamb = 25°C RL = 4Ω, Vcc = 3.
PAGE 14
TS4871 Fig. 51 : THD + N vs Frequency Fig. 52 : THD + N vs Frequency 1 Cb = 0.1µF Cb = 1µF RL = 8Ω Vcc = 5V Gv = 2 Pout = 450mW BW < 125kHz Tamb = 25°C THD + N (%) THD + N (%) 1 RL = 8Ω Vcc = 5V Gv = 2 Pout = 900mW BW < 125kHz Tamb = 25°C Cb = 0.1µF Cb = 1µF 0.1 100 1000 Frequency (Hz) Fig. 53 : THD + N vs Frequency THD + N (%) Cb = 0.1µF RL = 8Ω, Vcc = 5V Gv = 10 Pout = 450mW BW < 125kHz Tamb = 25°C Cb = 0.1µF 0.1 100 1000 Frequency (Hz) 10000 Fig.
PAGE 15
TS4871 RL = 8Ω, Vcc = 3.3V Gv = 10 Pout = 400mW BW < 125kHz Tamb = 25°C 1 THD + N (%) Fig. 58 : THD + N vs Frequency Cb = 0.1µF Cb = 1µF RL = 8Ω, Vcc = 3.3V Gv = 10 Pout = 200mW BW < 125kHz Tamb = 25°C 1 THD + N (%) Fig. 57 : THD + N vs Frequency Cb = 0.1µF Cb = 1µF 0.1 0.1 20 100 1000 Frequency (Hz) 10000 Fig. 59 : THD + N vs Frequency 20 100 1000 Frequency (Hz) 10000 Fig. 60 : THD + N vs Frequency 1 THD + N (%) Cb = 0.1µF RL = 8Ω, Vcc = 2.
PAGE 16
TS4871 Fig. 63 : THD + N vs Frequency Fig. 64 : THD + N vs Frequency 1 1 RL = 16Ω, Vcc = 5V Gv = 10, Cb = 1µF BW < 125kHz Tamb = 25°C THD + N (%) THD + N (%) RL = 16Ω, Vcc = 5V Gv = 2, Cb = 1µF BW < 125kHz Tamb = 25°C Pout = 310mW 0.1 Pout = 620mW 0.1 Pout = 310mW Pout = 620mW 0.01 20 100 1000 Frequency (Hz) 0.01 20 10000 Fig. 65 : THD + N vs Frequency 100 1000 Frequency (Hz) 10000 Fig. 66 : THD + N vs Frequency 1 1 THD + N (%) THD + N (%) RL = 16Ω, Vcc = 3.
PAGE 17
TS4871 Fig. 69 : Signal to Noise Ratio vs Power Supply with Unweighted Filter (20Hz to 20kHz) Fig. 70 : Signal to Noise Ratio vs Power Supply with Weighted Filter Type A 100 100 90 90 RL=4Ω RL=8Ω 80 SNR (dB) SNR (dB) RL=16Ω 70 Gv = 2 Cb = Cin = 1µF THD+N < 0.4% Tamb = 25°C 60 50 2.5 3.0 3.5 4.0 4.5 RL=8Ω RL=4Ω RL=16Ω 80 Gv = 10 Cb = Cin = 1µF THD+N < 0.7% Tamb = 25°C 70 60 2.5 5.0 3.0 3.5 Fig. 71 : Signal to Noise Ratio vs Power Supply with Weighted Filter type A 5.
PAGE 18
TS4871 Fig. 75 : Current Consumption vs Standby Voltage @ Vcc = 2.6V Fig. 76 : Current Consumption vs Standby Voltage @ Vcc = 3.3V 6 6 Vcc = 2.6V Tamb = 25°C 5 4 Icc (mA) Icc (mA) 4 3 3 2 2 1 1 0 0.0 0.5 1.0 1.5 Vstandby (V) 2.0 0 0.0 2.5 0.5 1.0 2.5 3.0 1.0 Tamb = 25°C 0.8 0.7 0.6 0.5 RL = 4Ω RL = 8Ω 0.4 0.3 0.2 0.1 RL = 16Ω 0.0 2.5 Tamb = 25°C 0.9 Vout1 & Vout2 Clipping Voltage Low side (V) 0.9 3.0 3.5 4.0 4.5 0.8 0.7 0.6 RL = 4Ω 0.5 RL = 8Ω 0.4 0.3 0.2 0.
PAGE 19
TS4871 APPLICATION INFORMATION Fig. 81 : Demoboard Schematic C1 R2 C2 R1 Vcc S1 Vcc Vcc S2 GND C6 + 100µ R3 6 C3 C5 R4 C4 Pos input P2 S6 Vcc Neg. input P1 C7 100n 4 R5 VinVin+ 3 - Vout1 5 + C9 + 470µ S5 Positive Input mode Vcc Av=-1 + Vcc R7 330k 2 Bypass 1 Standby S8 Standby Vout2 8 C10 + 470µ Bias GND D1 PW ON GND S4 GND S7 R6 R8 OUT1 S3 TS4871 7 C11 + C12 1u C8 Fig.
PAGE 20
TS4871 Fig. 83 : SO8 & MiniSO8 Demoboard Top Solder Layer The output power is: Pout = (2 Vout RMS ) 2 (W ) RL For the same power supply voltage, the output power in BTL configuration is four times higher than the output power in single ended configuration. ■ Gain In Typical Application Schematic (see page 1) In flat region (no effect of Cin), the output voltage of the first stage is: R fe ed Vout1 = – Vin -------------------- (V) Rin For the second stage : Vout2 = -Vout1 (V) Fig.
PAGE 21
TS4871 ■ Power dissipation and efficiency Hypothesis : • Voltage and current in the load are sinusoidal (Vout and Iout) • Supply voltage is a pure DC source (Vcc) Regarding the load we have: V O UT = V PEAK sin ωt (V) and V OU T I OU T = ----------------- (A) RL and VPEAK 2 P O U T = ---------------------- (W) 2 RL Then, the average current delivered by the supply voltage is: I CC AVG VPEAK = 2 -------------------- (A) πR L The power delivered by the supply voltage is Psupply = Vcc IccAVG (W) Then, the p
PAGE 22
TS4871 the internal generator resistance 50kΩ. Then, the charge time constant for Cb is τb = 50kΩxCb (s) As Cb is directly connected to the non-inverting input (pin 2 & 3) and if we want to minimize, in amplitude and duration, the output spike on Vout1 (pin 5), Cin must be charged faster than Cb. The charge time constant of Cin is τin = (Rin+Rfeed)xCin (s) Thus we have the relation τin << τb (s) 5Cs t D i s ch C s = -------------- = 83 ms Icc Now, we must consider the discharge time of Cb.
PAGE 23
TS4871 1 C IN = ------------------------------ = 795nF 2π RinF C L which gives 16Hz. In Higher frequency we want 20kHz (-3dB cut off frequency). The Gain Bandwidth Product of the TS4871 is 2MHz typical and doesn’t change when the amplifier delivers power into the load. The first amplifier has a gain of: Rfee d ----------------- = 3 R in and the theoretical value of the -3dB cut-off higher frequency is 2MHz/3 = 660kHz.
PAGE 24
TS4871 Designator Part Type Application n°4 : Differential inputs BTL power amplifier. C9 Short Circuit C10 Short Circuit C12 1µF S1, S2, S6, S7 2mm insulated Plug 10.16mm pitch We have also : R4 = R5, R1 = R6, C4 = C5. S8 3 pts connector 2.54mm pitch The gain of the amplifier is: P1 PCB Phono Jack D1* Led 3mm U1 TS4871ID or TS4871IS Application n°3 : 50Hz to 10kHz bandwidth and 10dB gain BTL power amplifier.
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TS4871 ■ Note on how to use the PSRR curves Fig. 86 : PSRR measurement schematic (page 7) We have finished a design and we have chosen the components values : Rfeed 6 • Rin=Rfeed=22kΩ • Cin=100nF • Cb=1µF Vcc Vripple Vcc 4 Rin 3 VinVin+ - Vout1 5 Vs- + Cin Rg 100 Ohms 2 Bypass 1 Standby Vout2 8 Vs+ Bias GND Now, on fig. 13, we can see the PSRR (input grounded) vs frequency curves. At 217Hz we have a PSRR value of -36dB. In reality we want a value about -70dB.
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TS4871 PACKAGE MECHANICAL DATA SO-8 MECHANICAL DATA DIM. mm. MIN. TYP inch MAX. MIN. TYP. MAX. A 1.35 1.75 0.053 0.069 A1 0.10 0.25 0.04 0.010 A2 1.10 1.65 0.043 0.065 B 0.33 0.51 0.013 0.020 C 0.19 0.25 0.007 0.010 D 4.80 5.00 0.189 0.197 E 3.80 4.00 0.150 0.157 e 1.27 0.050 H 5.80 6.20 0.228 0.244 h 0.25 0.50 0.010 0.020 L 0.40 1.27 0.016 0.050 k ddd 8˚ (max.) 0.1 0.
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TS4871 PACKAGE MECHANICAL DATA 27/28
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TS4871 PACKAGE MECHANICAL DATA Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice.