PAM8003 Filterless 2.5W Class-D Stereo Audio Amplifier Key Features General Description n 2.5W Output at 10% THD with a 4Ω Load and 5V Power Supply n 3W Output at 10% THD with a 3Ω Load and 5V Power Supply n Filterless, Low Quiescent Current and Low EMI n Low THD+N n 64-step DC Volume Control n Superior Low Noise n Short Circuit Protection n Thermal Shutdown n Few External Components to Save the Space and Cost n RoHS Pass and Green Package The PAM8003 is a 2.5W, class-D audio amplifier. It offers low THD+N, allowing it to achieve highquality sound reproduction. The new filterless architecture allows the device to drive the speaker directly, requiring no low-pass output filters, thus to save the system cost and PCB area. With the same numbers of external components, the efficiency of the PAM8003 is much better than that of class-AB cousins. It can extend the battery life, ideal for portable applications. The PAM8003 is available in SOP-16L package. Applications n LCD Monitors / TV n Notebook Computers n Portable Speakers n Portable DVD Players, Game Machines Typical Application VDD PVDD 1µF Ri INL INL +OUTL VREF -OUTL PAM8003 1µF 0.47µF INR Ri -OUTR INR VOLUME SHDN SHDN 1µF PVDDL PVDDR VDD 0.47µF 10µF 1µF +OUTR SHDN GND PGNDL PGNDR 联系电话：13826557935 1 联系人：熊伟 07/2010 Rev1.0 PAM8003 Filterless 2.5W Class-D Stereo Audio Amplifier Block Diagram VDD PVDDR PGNDR VDD/2 + - INR + - +OUTR DRIVER -OUTR MODULATOR VOLUME ATTENUATION DECODER INTERFACE CONTROL SHDN THERMAL PROTECTION BIAS AND REFERENCES INTERNAL OSCILLATOR OSC CURRENT PROTECTION MODULATOR - INL + VDD/2 VREF +OUTL DRIVER - -OUTL + GND PVDDL PGNDL Pin Configuration & Marking Information Top View SOP-16 16 PVDDR 15 -OUTR 14 PGNDR 13 +OUTR PAM8003 XATYWWLL PVDDL 1 -OUTL 2 PGNDL 3 +OUTL 4 SHDN 5 VREF 6 INL 7 GND 8 12 11 10 9 VOLUME NC INR VDD X: Internal Code A: Assembly Code T: Testing Code Y: Year WW: Week LL: Internal Code 联系电话：13826557935 2 联系人：熊伟 07/2010 Rev1.0 PAM8003 Filterless 2.5W Class-D Stereo Audio Amplifier Pin Descriptions Pin Number Pin Name Description 1 PVDDL Left Channel Power Supply 2 -OUTL Left Channel Negative Output 3 PGNDL Left Channel Power GND 4 +OUTL Left Channel Positive Output 5 SHDN Shutdown Control Input(active low) 6 VREF Internal analog reference, connect a bypass capacitor from VREF to GND 7 INL 8 GND Analog Ground 9 VDD Analog Power Supply 10 INR Right Channel Input 11 NC No Connected 12 VOLUME 13 +OUTR Right Channel Positive Output 14 PGNDR Right Channel Power GND 15 -OUTR Right Channel Negative Output 16 PVDDR Right Channel Power Supply Left Channel Input DC volume control to set the gain of Class-D Absolute Maximum Ratings These are stress ratings only and functional operation is not implied. Exposure to absolute maximum ratings for prolonged time periods may affect device reliability. All voltages are with respect to ground. Supply Voltage............................................6.0V Input Voltage.............................-0.3V to V DD+0.3V Maximum Junction Temperature..................150°C Storage Temperature.....................-65 °C to 150 °C Soldering Temperature....................... 300°C, 5sec Recommended Operating Conditions Supply voltage Range........................ 2.5V to 5.5V Operation Temperature Range.........-40 °C to 85 °C Junction Temperature Range.........-40 °C to 125 °C Thermal Information Parameter Symbol Package Maximum Unit Thermal Resistance (Junction to Ambient) θJA SOP-16L 110 °C/W Thermal Resistance (Junction to Case) θJC SOP-16L 23 °C/W 联系电话：13826557935 3 联系人：熊伟 07/2010 Rev1.0 PAM8003 Filterless 2.5W Class-D Stereo Audio Amplifier Electrical Characteristic V DD=5V, Gain=24dB, R L=8Ω, T A=25 °C , unless otherwise noted. Symbol Parameter VIN Supply Power Po Test Conditions MIN 2.5 2.75 W THD+N=1%,f=1kHz, RL=4 Ω VDD=5.0V 2.2 W THD+N=10%,f=1kHz, RL=8 Ω VDD=5.0V 1.65 W THD+N=1%,f=1kHz, RL=8 Ω VDD=5.0V 1.3 W Total Harmonic Distortion Plus VDD=3.6V,Po=0.5W,RL=8 Ω Noise VDD=5.0V,Po=1W,RL=4 Ω Power Supply Ripple Rejection Cs Crosstalk SNR Signal-to-noise ratio Vn Output noise 0.16 f=1kHz VDD=5.0V, Inputs ac-grounded with 0.17 f=1kHz Quiescent Current Rdson Shutdown Current Static Drain-to-source On-state Resistor % 0.26 f=1kHz -70 dB VDD=5V,Po=0.5W,RL=8Ω,Gv=20dB F=1kHz -93 dB VDD=5V, Gv=6dB f=1kHz 86 dB VDD=5V, Inputs ac-grounded with A-weighting 33 CIN=0.47µF,Gv=6dB No A-weighting 50 CIN=0.47µF,Gv=6dB RL=8Ω, THD=10% Efficiency % 0.12 µV 87 f=1kHz % RL=4Ω, THD=10% 79 VDD=5.0V 4.5 7 4 6.5 3.7 5.5 No load VDD=3.6V VDD=3.0V ISD V Output Power PSRR IQ 5.5 VDD=5.0V VDD=3.6V,Po=1W,RL=4 Ω η MAX UNIT THD+N=10%,f=1kHz, RL=4 Ω VDD=5.0V,Po=0.5W,RL=8 Ω THD+N TYP VDD=2.5V to 5.5V 1 IDS=500mA,Vgs=5V PMOS 0.41 NMOS 0.27 mA µA mΩ fsw Switching Frequency VDD=3V to 5V 210 kHz Vos Output Offset Voltage Vin=0V, VDD=5V 10 mV VIH Enable Input High Voltage VDD=5.0V VIL Enable Input Low Voltage VDD=5.0V OTP Over Temperature Protection OTH Over Temperature Hysterisis 1.5 No Load, Junction Temperature 联系电话：13826557935 4 V 0.4 VDD=5V 150 °C 30 联系人：熊伟 07/2010 Rev1.0 PAM8003 Filterless 2.5W Class-D Stereo Audio Amplifier Typical Operating Characteristics (T =25°C) A AudioPrecision 07/12/1018:50:03 1. THD+N vs Output Power 30 T T T A ud io Precision 30 T T 20 20 R L=4Ω R L=8Ω 10 10 5 5 V DD=3.6V 2 V DD=3.6V 2 % % 1 1 V DD=5V V DD=5V 0.5 0.5 0.2 0.2 0.1 1m 2m 5m 10m 20m 50m 100m 200m 500m 1 2 0.1 1m 3 2m 5m 1 0m 20m 5 0m AudioPrecision 07/13/1010:09:45 3. THD+N vs Frequency 10 5 T AudioPrecision 20 0m 500m 1 2 3 07/13/1009:56:36 4. THD+N vs Frequency 10 T R L=4Ω Po=0.5W R L=8Ω Po=0.5W 5 2 2 1 1 % % 0.5 0.5 R R 0.2 L 0.1 0.06 20 50 100 200 500 1k 0.2 L 0.1 2k 5k 10k 0.06 20 20k 50 100 200 500 AudioPrecision 07/13/1010:14:11 5. Frequency Response AudioPrecision +25 -50T +24.5 -55 +24 -60 +23.5 -65 +23 d B g +22.5 +21 +20.5 +20 10 2k 5k 10k 20k T 07/13/1012:02:45 6. Crosstalk T T T T T Gain=24dB R L=4Ω Vo=0.1Vrms Cin=1uF -70 d B +22 +21.5 1k Hz Hz A 100m W W 07 /12 /10 1 8:2 0:57 2. THD+N vs Output Power -75 -80 VDD=5V Gain=24dB R L=4Ω Vo=0.1Vrms Cin=1uF 20 50 L to R -85 -90 -95 100 200 500 1k 2k 5k 10k 20k -100 20 R to L 50 100 200 500 1k 2k 5k 10k 20k Hz Hz 联系电话：13826557935 5 联系人：熊伟 07/2010 Rev1.0 PAM8003 Filterless 2.5W Class-D Stereo Audio Amplifier Typical Operating Characteristics (continued) AudioPrecision -20 AudioPrecision 07/13/1014:11:35 7. PSRR -50 TT TTT -55 VDD=5V Vpp=200mV Gain=6dB R L=4Ω -25 -30 -35 -60 -65 -70 -75 -40 -45 d B 07/12/1019:15:27 8. FFT noise d B r -80 A -90 -85 -50 -55 -95 -60 -100 -105 -65 -110 -70 -115 -75 10 20 50 100 200 500 1k 2k 5k 10k 20k 50k -120 20 100k 50 100 200 500 Hz 1k 2k 5k 10k 20k Hz 9. Efficiency 10.Rdson VS Load Current 100 600 90 500 80 RDS(ON)(ohm) 60 50 40 30 20 4ohm 10 8ohm 400 300 200 PMOS 100 NMOS 0 0 0 500 1000 1500 2000 Output Power(m W) 2500 3000 0 500 11. Quiescent Current 1000 Load Current(m A) 1500 2000 5 6 12. Switching Frequency 6 220 5 215 210 4 Fsw(kHz) Quiescent Current(mA) Efficiency(%) 70 3 205 200 2 195 1 190 0 185 2 3 4 Input Votage(V) 5 6 联系电话：13826557935 6 2 3 4 Input Voltage(V) 联系人：熊伟 07/2010 Rev1.0 PAM8003 Filterless 2.5W Class-D Stereo Audio Amplifier Table 1. DC Volume Control STEP Gain (dB) STEP Gain (dB) 0 -75 32 11.6 1 -40 33 12 2 -34 34 12.4 3 -28 35 12.8 4 -22 36 13.2 5 -16 37 13.6 6 -10 38 14 7 -7.5 39 14.4 8 -5 40 14.8 9 -2.5 41 15.2 10 0 42 15.6 11 1.5 43 16 12 3 44 16.4 13 4 45 16.8 14 4.4 46 17.2 15 4.8 47 17.6 16 5.2 48 18 17 5.6 49 18.4 18 6 50 18.8 19 6.4 51 19.2 20 6.8 52 19.6 21 7.2 53 20 22 7.6 54 20.4 23 8 55 20.8 24 8.4 56 21.2 25 8.8 57 21.6 26 9.2 58 22 27 9.6 59 22.4 28 10 60 22.8 29 10.4 61 23.2 30 10.8 62 23.6 31 11.2 63 24 联系电话：13826557935 7 联系人：熊伟 07/2010 Rev1.0 PAM8003 Filterless 2.5W Class-D Stereo Audio Amplifier probably damage the device. Therefore, it's recommended to use either 4 Ni-MH (Nickel Metal Hydride) rechargeable batteries or 3 dry or alkaline batteries. Application Notes 1. When the PAM8003 works with LC filters, it should be connected with the speaker before it's powered on, otherwise it will be damaged easily. 4. One should not make the input signal too large. Large signal can cause the clipping of output signal when increasing the volume. This will damage the device b ecause of big gain of the PAM8003 . 2. When the PAM8003 works without LC filters, it's better to add a ferrite chip bead at the outgoing line of speaker for suppressing the possible electromagnetic interference. 5. When testing the PAM8003 without LC filters by using resistor instead of speaker as the output load, the test results, e.g. THD or efficiency, will be worse than those of using speaker as load. 3. The recommended operating voltage is 5.5V. When the PAM8003 is powered with 4 battery cells, it should be noted that the voltage of 4 new dry or alkaline batteries is over 6.0V, higher than its operation voltage, which will Test Setup for Performance Testing PAM8003 Demo Board Load +OUT AP System Generator Input AP Low Pass Filter GND -OUT AP System Analyzer AUX-0025 VDD Power Supply Notes 1. The AP AUX-0025 low pass filter is necessary for class-D amplifier measurement with AP analyzer. 2. Two 22µH inductors are used in series with load resistor to emulate the small speaker for efficiency measurement. 联系电话：13826557935 8 联系人：熊伟 07/2010 Rev1.0 PAM8003 Filterless 2.5W Class-D Stereo Audio Amplifier Application Information Power supply decoupling The PAM8003 is a high performance CMOS audio amplifier that requires adequate power supply decoupling to ensure the output THD and PSRR as low as possible. Power supply decoupling affects low frequency response. Optimum decoupling is achieved by using two capacitors of different types targeting to different types of noise on the power supply leads. For higher frequency transients, spikes, or digital hash on the line, a good low equivalent-seriesresistance (ESR) ceramic capacitor, typically 1.0µF, works best, placing it as close as possible to the device V DD terminal. For filtering lowerfrequency noise signals, a large capacitor of 20µF (ceramic) or greater is recommended, placing it near the audio power amplifier. Input Capacitor (C i) Large input capacitors are both expensive and space hungry for portable designs. Clearly, a certain sized capacitor is needed to couple in low frequencies without severe attenu ation. But in many cases the speakers used in portable systems, whether internal or external, have little ability to reproduce signals below 100Hz to 150Hz. Thus, using a large input capacitor may not increase actual system perfor mance. In this case, input capacitor (C i) and input resistance (R i) of the amplifier form a high-pass filter with the corner frequency determined by equation below. In addition to system cost and size, click and pop perfor mance is affected by the size of the input coupling capacitor, C i. A larger input coupling capacitor requires more charge to reach its quiescent DC voltage (nominally 1/2 V DD). This charge comes from the internal circuit via the feedback and is apt to create pops upon device enable. Thus, by minimizing the capacitor size based on necessary low frequency response, turn-on pops can be minimized. fC= 1 2πRiCi Analog Reference Bypass Capacitor (C BYP) from shutdown mode, C BYP determines the rate at which the amplifier starts up. The second function is to reduce noise caused by the power supply coupling into the output drive signal. This noise is from the internal analog reference to the amplifier, which appears as degraded PSRR and THD+N. A ceramic bypass capacitor (C BYP) with values of 0.1µF to 1.0µF is recommended for the best THD and noise performance. Increasing the bypass capacitor reduces clicking and popping noise from power on/off and entering and leaving shutdown. Under Voltage Lock-out (UVLO) The PAM8003 incorporates circuitry designed to detect low supply voltage. When the supply voltage drops to 2.0V or below, the PAM8003 outputs are disabled, and the device comes out of this state and starts to normal function when V DD ≥2.2V. Short Circuit Protection (SCP) T h e PA M 8 0 0 3 h a s s h o r t c i r c u i t p r o t e c t i o n circuitry on the outputs to prevent damage to the device when output-to-output or output-to-GND short occurs. When a short circuit is detected on the outputs, the outputs are disabled immediately. If the short was removed, the device activates again. Over Temperature Protection Thermal protection on the PAM8003 prevents the device from damage when the internal die temperature exceeds 140°C. There is a 15 degree tolerance on this trip point from device to device. Once the die temperature exceeds the thermal set point, the device outputs are disabled. This is not a latched fault. The thermal fault is cleared once the temperature of the die is reduced by 30°C. This large hysteresis will prevent motor boating sound well and the device begins normal operation at this point without external system intervention. The Analog Reference Bypass Capacitor (C BYP) is the most critical capacitor and serves several important functions. DuAring start-up or recovery 联系电话：13826557935 9 联系人：熊伟 07/2010 Rev1.0 PAM8003 Filterless 2.5W Class-D Stereo Audio Amplifier How to Reduce EMI (Electro Magnetic Interference) A simple solution is to put an additional capacitor 1000μF at power supply terminal for power line coupling if the traces from amplifier to speakers are short (<20cm). Most applications require a ferrite bead filter as shown in Figure 2. The ferrite filter reduces EMI of around 1 MHz and higher. When selecting a ferrite bead, choose one with high impedance at high frequencies, and low impedance at low frequencies. Ferrite Bead OUT+ 220pF Ferrite Bead OUT220pF Figure 2: Ferrite Bead Filter to reduce EMI 联系电话：13826557935 10 联系人：熊伟 07/2010 Rev1.0 PAM8003 Filterless 2.5W Class-D Stereo Audio Amplifier Ordering Information PAM8003 X X Shipping Package Package Type Part Number PAM8003DR Marking Package Type MOQ/Shipping Package SOP-16L 2,500 Units/Tape&Reel PAM8003 XATYWWLL 联系电话：13826557935 11 联系人：熊伟 07/2010 Rev1.0 PAM8003 Filterless 2.5W Class-D Stereo Audio Amplifier Outline Dimension A1 A A2 SOP-16 B D E E1 L C θ e Symbol Dimensions Millimeters Min Max A 1.350 1.750 A1 0.100 0.250 A2 1.350 1.550 B 0.330 0.510 C 0.190 0.250 D 9.800 10.000 E 3.800 4.000 E1 5.800 6.300 e 1.270(TYP) L 0.400 1.270 θ 0º 8º 联系电话：13826557935 12 联系人：熊伟 07/2010 Rev1.0