PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit Key Features General Description The PAM8620 is a 15W (per channel) stereo class-D audio amplifier which offers low THD+N (0.2%), low EMI, and good PSRR thus highquality sound reproduction. n 15Wx2 into a 8Ω speaker n Low Noise: -90dB n Over 90% Efficiency n With Shutdown/Mute Function n Over Current ,OVP,UVLO,Thermal and ShortCircuit Protection n Low THD+N n Power Limit with Non-clip n Low Quiescent Current n Pop noise suppression n Small Package Outlines: QFN5x5-32L n Pb-Free Package (RoHS Compliant) The PAM8620 runs off of a 8V to 26V supply at much higher efficiency than competitors’ Ics. The PAM8620 only requires very few external components, significantly saving cost and board space. The PAM8620 is available in a QFN5x5-32L package. Applications n Flat monitor /LCD TVS n Multi-media speaker System n DVD players, game machines n Boom Box n Music instruments 1μF 1μF 10μF RINP 1μF 1μF PGNDR ROUTP BSRP BSRN ROUTN 10μF PVCCR PGNDR RINN GND PVCCR 1μF 1μF PVCCR GND PVCCR Typical Application 1μF VCLAMP RINN GND RINP SHUTDOWN SD GND 1μF MUTE AGND AVDD GND PAM8620 MUTE 1μF V2P5 GND AVCC LINN 1uF VCC 1μF 1μF PGNDL 10μF GND 1μF PVCCL GND 1μF PVCCL 10μF PVCCL BSLP PVCCL LOUTP PL BSLN 1μF 10μF LINP PGNDL LINN 1μF LOUTN LINP Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 1 PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit Block Diagram BSRN PVCCR Ri - RINN RINP + _ + - ROUTN Driver Rf PGNDR BSRP PVCCR Modulation/ Power Limit + _ + Ri Driver Rf ROUTP PGNDR Feedback System (x6) AVCC Power Limit Reference PL VCLAMP AGND LDO on/off Depop UVLO Thermal Short Circuit Protection AVDD SD Biases & References LDO BSLN V2P5 PVCCL MUTE Driver Rf Ri LINN - LINP + _ + - PGNDL BSLP PVCCL Modulation/ Power Limit + _ + LOUTN Ri Driver Rf LOUTP PGNDL Feedback System (x6) Note: Maximum Gain: Ri=12.5k, Rf=100k; Power Limit Function: Ri and Rf are adjustable. Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 2 PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit Pin Configuration & Marking Information PGNDR PVCCR ROUTN BSRN BSRP ROUTP PVCCR PGNDR Top View QFN5x5-32L 32 31 30 29 28 27 26 25 NC 1 24 NC RINN 2 23 SD RINP 3 22 AVCC MUTE 4 21 VCLAMP AVDD 5 20 AGND LINP 6 19 V2P5 LINN 7 18 PL NC 8 17 NC 9 10 11 12 13 14 15 16 PGNDL PVCCL LOUTN BSLN BSLP LOUTP PVCCL PGNDL PAM8620 XXXYWWLL XXX: Internal Code Y: Year WW: Week LL: Internal Code Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 3 PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit Pin Descriptions Pin No. Name Function 1,8,17,24 NC 2 RINN Negative differential audio input for right channel 3 RINP Positive differential audio input for right channel 4 MUTE 5 AVDD 5V Analog Supply 6 LINP Positive differential audio input for left channel 7 LINN Negative differential audio input for left channel 9,16 PGNDL Power ground for left channel H-bridge 10,15 PVCCL Power supply for left channel H-bridge, not connected to PVCCR or AVCC. 11 LOUTN Class-D 1/2-H-bridge negative output for left channel 12 BSLN Bootstrap I/O for left channel, negative high-side FET 13 BSLP Bootstrap I/O for left channel, positive high-side FET 14 LOUTP Class-D 1/2-H-bridge positive output for left channel 18 PL 19 V2P5 2.5V Reference for analog cells 20 AGND Analog Ground 21 VCLAMP 22 AVCC 23 SD 25,32 PGNDR 26,31 PVCCR 27 ROUTP Class-D 1/2-H-bridge positive output for right channel 28 BSRP Bootstrap I/O for right channel, positive high-side FET 29 BSRN Bootstrap I/O for right channel, negative high-side FET 30 ROUTN Class-D 1/2-H-bridge negative output for right channel 33 Thermal Pad No Connected A logic high on this pin disables the outputs and a logic low enables the outputs. Reference voltage for power limit function Internally generated voltage supply for bootstrap capacitors. High-voltage analog power supply (8V to 26V) Shutdown signal for IC (low= shutdown, high =operational). TTL logic levels with compliance to VCC. Power ground for right channel H-bridge Power supply for right channel H-bridge, not connected to PVCCL or AVCC. Connect to ground. Thermal pad should be soldered down on all applications to secure the device properly to the printed wiring board. Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 4 PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit 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. Junction Temperature Range,T J......-40°C to 125 °C Storage Temperature.....................-65 °C to150 °C Lead Temperature1,6mm(1/16 inch) from case for 5 seconds.................................................260 °C Supply Voltage VCC...........................-0.3V to 28V Input Voltage Range V I: MUTE, PL............................................0V to 6.0V SD..................................................-0.3V to VCC RINN,RINP,LINN,LINP......................-0.3V to 6.0V Recommended Operating Conditions Low Level Input Voltage: SD...................0 to 0.3V MUTE...............0 to 0.3V Ambient Operating Temperature......-20 °C to 85 °C Supply Voltage (VCC)....... ....................8V to 26V Input Pin Voltage..................................0V to 5.5V High Level Input Voltage: SD..............2.0V to VCC MUTE. ...... ..2.0V to 5.5V Thermal Information Parameter Thermal Resistance (Junction to Case) Thermal Resistance (Junction to Ambient) Package Symbol Maximum QFN 5x5-32L θJC 5.0 Unit °C/W QFN 5x5-32L θJA 16.1 The Exposed PAD must be soldered to a thermal land on the PCB. Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 5 PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit Electrical Characteristic T A=25 °C ,VCC=12V,R L=8Ω (unless otherwise noted) Parameter Symbol Condition MIN THD+N=0.12%,f=1kHz,RL =8Ω Continuous Output Power Quiescent Current Supply Quiescent Current in shutdown mode Drain-source on-state resistance Power Supply Ripple Rejection Ratio Po 8.5 THD+N=10%,f=1kHz,RL=8Ω 10 (no load) ISD SHUTDOWN=0V PSRR IO=0.5A T J=25℃ W 25 mA 4 10 µA 210 Low side 210 Total 420 ac-coupled to ground Units 16.5 High side 1VPP ripple, f=1kHz, Inputs MAX 6 THD+N=1%,f=1kHz,RL=8Ω IDD rds(on) TYP mΩ -65 dB 300 kHz Oscillator Frequency f OSC Output Integrated Noise Floor Vn 20Hz to 22 kHz, A-weighting -100 dB Crosstalk CS PO=3W, RL=8Ω , f=1kHz -95 dB 90 dB 32 dB Signal to Noise Ratio SNR Maximum output at THD+N< 0.5%, f=1kHz Gain Output offset voltage |VOS | INN and INP connected together 30 mV 2.5V Bias voltage V2P5 No Load 2.5 V Internal Analog supply Voltage AVDD VCC=8V to 26V Over Temperature Shutdown OTS 160 °C Thermal Hysteresis OTH 50 °C (measured differentially) 5 5.5 V Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 6 PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit Electrical Characteristic T A=25 °C ,VCC=24V,R L=8Ω (unless otherwise noted) Parameter Continuous Output Power Total Harmonic Distortion plus Noise Quiescent Current Supply Quiescent Current in shutdown mode Drain-source on-state resistance Power Supply Ripple Rejection Ratio Symbol Po THD+N Condition MIN THD+N=0.09%,f=1kHz,RL =8Ω 5 THD+N=0.25%,f=1kHz,RL =8Ω 15 PO=7.5W,f=1kHz,RL=8Ω , IDD (no load) ISD SHUTDOWN=0V rds(on) PSRR TYP T J=25℃ High side 210 Low side 210 Total 420 1VPP ripple, f=1kHz, Inputs ac-coupled to ground Units W 0.12 20 IO=0.5A MAX % 30 mA 50 µA mΩ -65 dB 300 kHz Oscillator Frequency f OSC Output Integrated Noise Floor Vn 20Hz to 22 kHz, A-weighting -100 dB Crosstalk CS PO=3W, RL=8Ω , f=1kHz -95 dB 90 dB 32 dB Signal to Noise Ratio SNR Maximum output at THD+N< 0.5%, f=1kHz Gain Output offset voltage |VOS | INN and INP connected together 30 mV 2.5V Bias voltage V2P5 No Load 2.5 V Internal Analog supply Voltage AVDD VCC=8V to 26V Over Temperature Shutdown OTS 160 °C Thermal Hysteresis OTH 50 °C (measured differentially) 5 5.5 V Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 7 PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit Typical Performance Characteristics VCC=24V,R L=8Ω, Gv=32dB,Τ Α=25°C, unless otherwise noted. Audio Precision 11/11/11 14:46:35 AudioPrecision 1. THD +N vs Power (VCC=12V) 10/27/1113:31:35 2. THD+N vs Power (VCC=24V) 20 20 10 10 5 5 80 10 1 2 2 % 100mW % 1 f=10kHz 1 f=1kHz 0.5 10m 0.5 0.2 0.1 1m 2m 5m 10m 20m 50m 100m 500m 1 W Audio Precision 2 5 0.1 10 20 11/11/11 15:00:44 10 1 2 53 1 1 1 Line Style Thick Data Red Solid Magenta Solid Blue Solid 2 2 2 Axis Anlr.THD+N Ratio Left Anlr.THD+N Ratio Left Anlr.THD+N Ratio Left 200m 400m 600m 800m 2 100u 11/11/11 15:03:04 Sweep Trace Color 10 1k 10k 5 8 8 1 2 Magenta Solid Magenta Solid 4 4 Anlr.THD+NRatio Left 150k Anlr.LevelA Right 150k 1 Po=1W Po=10W % Po=3W 0.5 Po=5W 0.5 0.2 0.2 0.1 0.1 Po=5W 0.06 20 50 100 200 500 1k 2k 5k 10k Po=3W 0.06 20 20k 50 100 200 500 Hz Line Style Thick Data 2 2 2 Anlr.THD+N Ratio Left Anlr.THD+N Ratio Left Anlr.THD+N Ratio Left Hz Sweep Trace Color Line Style Thick Data Axis 5. Frequency Response 1 2 3 + 36 1 1 1 Red Magenta Blue Cin=2.2uF Solid Solid Solid 2 2 2 Anlr.THD+N Ratio Anlr.THD+N Ratio Anlr.THD+N Ratio Sweep Trace Color Comment 1 +0 2 3 Left Left Left 6. 1Crosstalk Red Solid 1T 1 Magenta Solid Blue Solid 1k 2k 5k Axis 10k 20k Comment -10 THD plus N vs Freqency8620.at2c -20 THD plus N vs Freqency8620.at2c + 34 -30 + 32 -40 + 30 + 28 Cin=1uF + 26 -50 d B Cin=0.47uF + 24 L to R -60 -70 + 22 -80 + 20 + 18 -90 Cin=0.1uF + 16 -100 R to L + 14 -110 + 12 + 10 1.8 THD+NVsPO8620.at2c 1 A 1.6 2 % d B g 1.4 Vrms THD+N Vs PO 8620.at2c + 38 1.2 LineStyle Thvs ick DataFrequency Axis Comment (VCC=24V) 4. THD+N Comment 2 + 40 1 Audio Precision 3. THD+N vs Frequency (VCC=12V) Sweep Trace Color 1m 0.2 f=100Hz 20 50 100 200 500 1k 2k 5k 10 k -120 20 20 k 50 100 200 500 1k 2k 5k 10 k 20k Hz Hz Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 8 PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit Typical Performance Characteristics VCC=24V,R L=8Ω, Gv=32dB,Τ Α=25°C, unless otherwise noted. Audio Precision 10/21/11 16:19:03 7. PSRR +0 8. Noise Floor +0 T T - 10 -10 - 20 -20 - 30 - 40 -30 d B VCC=12V -40 d B r - 50 A - 70 - 60 -50 - 80 -60 - 90 - 100 -70 VCC=24V -80 10 - 110 - 120 20 50 100 200 500 1k 2k 5k 10k 20k 100k 20 50 100 Sweep Trace Color Line Style Thick Data Axis Comment 9. Efficiency vs Output Power (VCC=12V) 1001 3 1 1 Red Blue Solid Solid 2 2 1k 2k 5k 10 k 20 k 10. Efficiency vs Output Power (VCC=24V) 90 PSRR-8620.at2 80 70 Efficiency(%) 70 Efficiency(%) 500 100 Anlr.Crosstalk Left Anlr.Crosstalk Left 90 80 200 Hz Hz 60 50 40 60 50 40 30 30 20 20 10 10 0 0 0 2 4 6 8 10 12 0 3 Output Power(mW ) 11. PL Voltage vs Output Power 6 9 O utput Power(W ) 12 15 12. Quiescent Current vs Supply Voltage 20 25 19.5 19 Quiescent Current(mA) Output power(W) 20 15 10 5 18.5 18 17.5 17 16.5 16 15.5 0 15 0.4 0.6 0.8 1 1.2 PL Volatage(V) 1.4 1.6 6 11 16 21 Supply Voltage(V) 26 31 Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 9 PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit Test Setup for Performance Testing PAM8620 Demo Board Load +OUT AP System One Generator Input AP Low Pass Filter GND -OUT AP System Two Analyzer AUX-0025 VCC 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. Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 10 PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit Application Information decoupling to ensure the output total harmonic distortion (THD) as low as possible. Power supply decoupling also prevents oscillations caused by long lead between the amplifier and the speaker. The optimum decoupling is achieved by using two capacitors of different types that target 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 1µF, is recommended, placing as close as possible to the device’s VCC lead. To filter lowerfrequency noises, a large aluminum electrolytic capacitor of 10µF or greater is recommended, placing near the audio power amplifier. The 10µF capacitor also serves as a local storage capacitor for supplying current during large signal transients on the amplifier outputs. MUTE Operation The MUTE pin is an input for controlling the output state of the PAM8620. A logic high on this pin disables the outputs and low enables the outputs. This pin may be used as a quick disable or enable of the outputs without a volume fade. Shutdown Operation The PAM8620 employs a shutdown operation mode to reduce supply current to the absolute minimum level during periods of non-use to save power. The SD input terminal should be held high during normal operation when the amplifier is in use. Pulling SD low causes the outputs to mute and the amplifier to enter a low-current state. SD should never be left unconnected to prevent the amplifier from unpredictable operation. BSN and BSP Capacitors For the best power-off pop performance, the amplifier should be set in shutdown mode prior to removing the power supply voltage. The full H-bridge output stages use NMOS transistors only. They therefore require bootstrap capacitors for the high side of each output to turn on correctly. A at least 220nF ceramic capacitor, rated for at least 25V, must be connected from each output to its corresponding bootstrap input. Specifically, one 220nF capacitor must be connected from xOUTP to xBSP, and another 220nF capacitor from xOUTN to xBSN. It is recommended to use 1μF BST capacitor to replace 220nF or lower than 100Hz applications. Internal 2.5V Bias Generator Capacitor Selection The internal 2.5V bias generator (V2P5) provides the internal bias for the preamplifier stage. The external input capacitors and this internal reference allow the inputs to be biased within the optimal common-mode range of the input preamplifiers. VCLAMP Capacitors The selection of the capacitor value on the V2P5 terminal is critical for achieving the best device performance. During startup or recovery from shutdown state, the V2P5 capacitor determines the rate at which the amplifier starts up. When the voltage on the V2P5 capacitor equals 0.75 x V2P5, or 75% of its final value, the device turns on and the class-D outputs start switching. The startup time is not critical for the best de-pop performance since any heard pop sound is the result of the class-D output switching-on other than that of the startup time. However, at least a 0.47µF capacitor is recommended for the V2P5 capacitor. Another function of the V2P5 capacitor is to filter high frequency noise on the internal 2.5V bias generator. To ensure that the maximum gate-to-source voltage for the NMOS output transistors not exceeded, a internal regulators are used to clamp the gate voltage. A 1µF capacitors must be connected from VCLAMP to ground and must be rated for at least 25V. The voltages at the VCLAMP terminals vary with V CC and may not be used to power any other circuitry. Internal Regulated 5-V Supply (AVDD) The AVDD terminal is the output of an internallygenerated 5V supply, used for the oscillator, amplifier,power limit circuitry and logic control circuitry. It requires a 0.1µF to 1µF capacitor, placed very close to the pin to Ground to keep the regulator stable. The regulator may not be used to power any external circuitry. Power Supply Decoupling, C S The PAM8620 is a high-performance CMOS audio amplifier that requires adequate power supply Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 11 PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit Differential Input Power Limit The differential input stage of the amplifier eliminates noises that appear on the two input lines of the channel. To use the PAM8620 with a differential source, connect the positive lead of the audio source to the INP input and the negative lead from the audio source to the INN input. To use the PAM8620 with a single-ended source, acground the INP input through a capacitor equal in value to the input capacitor on INN and apply the audio source to the INN input. In a single-ended input application, the INP input should be acgrounded at the audio source other than at the device input for best noise performance. The voltage at PL pin can used to limit the power to levels below that which is possible based on the supply rail. Add a resistor from PL to ground to set the voltage at the PLIMIT pin. An external reference may also be used if tighter tolerance is required. Also add a 1uF capacitor fromPL pin to ground. The PLIMIT circuit sets a limit on the output peak-to-peak voltage. The gain of class D amplifier will automatic reduced if the output power higher than setting value to make output power less than limited value and also provide good sound quality. The output power vs PL pin resistor value as below. VCC=24V,Rload=8 Ω Using low-ESR Capacitors Low-ESR capacitors are recommended throughout this application section. A real (with respect to ideal) capacitor can be modeled simply as a resistor in series with an ideal capacitor. The voltage drop across this resistor minimizes the beneficial effects of the capacitor in the circuit. The lower the equivalent value of this resistance the more the real capacitor behaves as an ideal capacitor. Short-circuit Protection The PAM8620 has short circuit protection circuitry on the outputs to prevent damage to the device when output-to-output shorts, output-to-GND shorts, or output-to-VCCshorts occur. Once a short-circuit is detected on the outputs, the output drive is immediately disabled. This is a latched fault and must be reset by cycling the voltage on the SD pin to a logic low and back to the logic high state for normal operation. This will clear the short-circuit flag and allow for normal operation if the short was removed. If the short was not removed, the protection circuitry will again activate. R(Ω) PL (V) PL(W) R(Ω) PL (V) PL(W) 56K 62K 0.62 0.68 3.2 3.8 110K 120K 1.08 1.15 9.6 11.0 68K 0.73 4.4 130K 1.23 12.4 75K 0.79 5.2 150K 1.36 15.5 82K 91K 0.86 0.93 6.1 7.1 160K 180K 1.43 1.55 17.0 19.9 100K 1.00 8.2 200K 1.66 22.9 VCC=12V,Rload=8 Ω R(Ω) PL (V) PL(W) R(Ω) PL (V) PL(W) 56K 62K 0.61 0.67 3.1 3.7 100K 110K 0.99 1.07 8.1 9.0 68K 0.73 4.3 120K 1.15 9.6 75K 0.79 5.1 130K 1.22 10.0 82K 91K 0.85 0.92 6.0 7.0 140K 1.36 10.7 Thermal Protection Thermal protection on the PAM8620 prevents damage to the device when the internal die temperature exceeds 160°C. There is a ±15 degree tolerance on this trip point from device to device. Once the die temperature exceeds the set thermal point, the device enters into the shutdown state and the outputs are disabled. This is not a latched fault. The thermal fault is cleared once the temperature of the die is reduced by 50°C. The device begins normal operation at this point without external system intervention. Soft Clip PAM Plimit Hard Clip Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 12 PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit Power Up/Down Sequence The PAM8620 employs a shutdown operation mode to reduce supply current to the absolute minimum level during periods of non-use to save power. The SD input terminal should be held high during normal operation when the amplifier is in use. Pulling SD low causes the outputs to mute and the amplifier to enter a low-current state. SD should never be left unconnected to prevent the amplifier from unpredictable operation. Suggest PL starting voltage is greater than 5V. Start-up /power down sequencer recommended Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 13 PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit Ordering Information PAM8620 X X Shipping Package Type Please consult PAM sales office or authorized distributors for more details. Part Number PAM8620TR Marking PAM8620 XXXYWWLL Package Type Standard Package QFN5x5-32L 3,000 units/Tape & Reel Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 14 PAM8620 15W Stereo Class-D Audio Power Amplifier with Power Limit Outline Dimension QFN5x5-32L Power Analog Microelectronics,Inc www.poweranalog.com 10/2012 Rev1.0 15