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NCP2821 2.65 W Filterless with Selectable Gain Class-D Audio Amplifier NCP2821 is a cost effective mono audio power amplifier designed for portable communication device applications such as mobile phones. The internal gain setting between 6 dB and 12 dB will also save external gain setting resistors. To achieve a typical audio mono application, you only need an external capacitor for filtering the power supply. The NCP2821 processes analog inputs with a PWM technique that lowers significantly output noise and THD. This part is capable of delivering 2.65 W of continuous average power to a 4.0 W BTL load from a 5.0 V power supply. Operating on a single 3 V supply, the output power stage can provide 500 mW to an 8.0 W BTL load with less than 1% THD+N. For cellular handsets or PDAs it offers space and cost savings because no output filter is required when using inductive transducers. Its improved Class-D technology makes it suitable for portable devices. With 90% efficiency and very low shutdown current, it increases widely the lifetime of your battery compared to a ClassAB solution. It also minimizes the junction temperature. It fully rejects "pop & click" noises with a fast start-up time of 9 ms. Added to a -65 dB PSRR, the NCP2821 audio power amplifier is specifically designed to provide high quality output power from low supply voltage, requiring only 1 external capacitor. Features http://onsemi.com MARKING DIAGRAM 9-PIN FLIP-CHIP CSP FC SUFFIX CASE 499AL MAU A Y WW G MAUG AYWW 1 A1 = Device Code = Assembly Location = Year = Work Week = Pb-Free Package PIN CONNECTIONS 9-Pin Flip-Chip CSP A1 INP B1 A2 GS B2 VP C2 A3 OUTM B3 GND C3 * Optimized PWM Output Stage: Filterless Capability * Selectable Gain of 6 dB or 12 dB: No Need for External Gain Setting * Efficiency up to 90% and Low Quiescent Current * * * * * * * * * * * * Maximum Battery Life and Minimum Heat High Output Power Capability: 1.4 W with 8.0 W Load Wide Supply Voltage Range: 2.5-5.5 V Operating Voltage High Performance, THD+N of 0.05% Excellent PSRR (-65 dB): No Need for Voltage Regulation Surface Mounted Package 9-Pin Flip-Chip CSP Fully Differential Capability: No Need for Input Coupling Capacitor Very Fast Turn On Time: 9.0 ms (typ) "Pop and Click" Noise Protection Circuitry Resistors VP C1 INM SD OUTP (Top View) ORDERING INFORMATION See detailed ordering and shipping information on page 18 of this data sheet. 1 mF Audio Input from DAC Input from Micro controller VP INP INM GS SD OUTM OUTP Applications Cellular Phone Personal Computer PDAs Portable Electronic Devices GND Cs 1.6 mm 2.7 mm Solution Size (c) Semiconductor Components Industries, LLC, 2006 1 February, 2006 - Rev. 0 Publication Order Number: NCP2821/D NCP2821 BATTERY Cs Negative Differential Input Vp INM Ri Rf OUTP RAMP GENERATOR Vih Vil GS Gain Control Data Processor CMOS Output Stage OUTM Rf INP Ri 300 kW Positive Differential Input Vih Vil SD Shutdown Control GND Figure 1. Typical Application PIN DESCRIPTION Pin No. A1 A2 A3 B1 B2 B3 C1 C2 C3 Symbol INP GS OUTM Vp Vp GND INM SD OUTP Type I I O I I I I I O Positive Differential Input. Gain Select Input. Negative BTL Output. Power Analog Positive Supply. Range: 2.5 V - 5.5 V. Power Analog Positive Supply. Range: 2.5 V - 5.5 V. Analog Ground. Negative Differential Input. Shutdown Input. Positive BTL Output. Description http://onsemi.com 2 RL = 8 W GS NCP2821 MAXIMUM RATINGS Rating Supply Voltage Operating Supply Voltage Input Voltage Power Dissipation (Note 1) Operating Ambient Temperature Max Junction Temperature Storage Temperature Range Thermal Resistance Junction-to-Air ESD Protection Human Body Model (HBM) (Note 3) Machine Model (MM) (Note 4) Latchup Current @ TA = 85C (Note 5) Symbol Vp Op Vp Vin Pd TA TJ Tstg RqJA - - - Max 6.0 2.5 to 5.5 -0.3 to Vp +0.3 Internally Limited -40 to +85 150 -65 to +150 90 (Note 2) > 2000 > 200 $100 Unit V V V - C C C C/W V mA Maximum ratings are those values beyond which device damage can occur. Maximum ratings applied to the device are individual stress limit values (not normal operating conditions) and are not valid simultaneously. If these limits are exceeded, device functional operation is not implied, damage may occur and reliability may be affected. 1. The thermal shutdown is set to 160C (typical) avoiding irreversible damage to the device due to power dissipation. 2. For the 9-Pin Flip-Chip CSP package, the RqJA is highly dependent of the PCB Heatsink area. For example, RqJA can equal 195C/W with 50 mm2 total area and also 135C/W with 500 mm2. When using ground and power planes, the value is around 90C/W, as specified in table. 3. Human Body Model: 100 pF discharged through a 1.5 kW resistor following specification JESD22/A114. 4. Machine Model: 200 pF discharged through all pins following specification JESD22/A115. 5. Latchup Testing per JEDEC Standard JESD78. SD and GS are qualified at 70 mA versus 100 mA for the other pins. http://onsemi.com 3 NCP2821 ELECTRICAL CHARACTERISTICS (Limits apply for TA = +25C unless otherwise noted) Characteristic Operating Supply Voltage Supply Quiescent Current Symbol VP Idd Conditions TA = -40C to +85C VP = 3.6 V, RL = 8.0 W VP = 5.5 V, No Load VP from 2.5 V to 5.5 V, No Load TA = -40C to +85C Vp = 4.2 V, TA = +25C Vp = 5.5 V, TA = +25C Vp = 2.5 V to 5.5 V TA = -40C to +85C SD Voltage High SD Voltage Low GS Voltage High GS Voltage Low Differential Input Resistance Switching Frequency Gain Resistance from SD to Gnd Output Offset Voltage Turn On Time Turn Off Time Thermal Shutdown Temperature Output Noise Voltage Vsdih Vsdil Vgsih Vgsil Rin FSW G RSD Vos TON TOFF Tsd Vn Vp = 3.6 V F = 20Hz to 20kHz No weighting filter A weighting filter RL = 8 W, f = 1 kHz, THD+N < 1% Vp = 2.5 V Vp = 3.0 V Vp = 3.6 V Vp = 4.2 V Vp = 5.0 V RL = 8 W, f = 1 kHz, THD+N < 10% Vp = 2.5 V Vp = 3.0 V Vp = 3.6 V Vp = 4.2 V Vp = 5.0 V RMS Output Power Po RL = 4 W, f = 1 kHz, THD+N < 1% Vp = 2.5 V Vp = 3.0 V Vp = 3.6 V Vp = 4.2 V Vp = 5.0 V RL = 4 W, f = 1 kHz, THD+N < 10% Vp = 2.5 V Vp = 3.0 V Vp = 3.6 V Vp = 4.2 V Vp = 5.0 V TA = -40C to +85C Vp = 2.5 V to 5.5 V Vp = 2.5 V to 5.5 V G = 6 dB G = 12 dB Vp = 2.5 V to 5.5 V TA = -40C to +85C RL = 8.0 W, VGS = High RL = 8.0 W, VGS = Low Min 2.5 - - - - - - - - 1.2 - 1.2 - - - 200 5.5 11.5 200 -25 - - - - - - - - - - - - - - - - - - - - - - - - - - Typ - 2.5 3.1 - - 0.5 0.8 - - - - - - 150 75 250 6 12 300 2.5 9 5 160 - - 1.4 - 0.4 - 0.4 - - 300 6.5 12.5 - +25 - - - - - - W 0.32 0.48 0.7 0.97 1.38 0.4 0.59 0.87 1.19 1.7 0.49 0.72 1.06 1.62 2.12 0.6 0.9 1.33 2.0 2.65 - - - - - W - - - - - W - - - - - W - - - - - dB dB kW mV ms ms C mVrms 63 40 Max 5.5 - - - 4.5 Unit V mA Shutdown Current Isd mA mA V V V V kW kW kHz RMS Output Power Po http://onsemi.com 4 NCP2821 ELECTRICAL CHARACTERISTICS (Limits apply for TA = +25C unless otherwise noted) Characteristic Total Harmonic Distortion + Noise Symbol THD+N Conditions Vp = 5.0 V, RL = 8 W, f = 1 kHz, Pout = 0.25 W Vp = 3.6 V, RL = 8 W, f = 1 kHz, Pout = 0.25 W RL = 8 W, f = 1 kHz Vp = 5 V, Pout = 1.2 W Vp = 3.6 V, Pout = 600 mW RL = 4 W, f = 1 kHz Vp = 5 V, Pout = 2 W Vp = 3.6 V, Pout = 600 mW Common Mode Rejection Ratio CMRR Vp = 2.5 V to 5.5 V, G = 6 dB Vic = 0.5 V to Vp - 0.8 V Vp = 3.6 V, Vic = 1 Vpp G = 6 dB, f = 1 kHz G = 12 dB, f = 1 kHz Vpripple_pk-pk = 200 mV, RL = 8 W, Inputs AC grounded, Vp = 3.6 V f = 217 Hz f = 1 kHz Min - - - - - - Typ 0.05 0.09 91 90 82 81 -62 -59 -53 dB -63 -63 - - Max - - % - - % - - dB Unit % Efficiency h Power Supply Rejection Ratio PSRR - Ci + Audio Input Signal - Ri INP NCP2821 OUTM Load 30 kHz Low Pass Filter - + Measurement Input Ci Ri INM VP OUTP GND 4.7 mF + Power Supply - Figure 2. Test Setup for Graphs NOTES: 1. Unless otherwise noted, Ci = 100 nF and Ri= 150 kW. Thus, the gain setting is 2 V/V and the cutoff frequency of the input high pass filter is set to 10 Hz. Input capacitors are shorted for CMRR measurements. 2. To closely reproduce a real application case, all measurements are performed using the following loads: RL = 8 W means Load = 15 mH + 8 W + 15 mH RL = 4 W means Load = 15 mH + 4 W + 15 mH Very low DCR 15 mH inductors (50 mW) have been used for the following graphs. Thus, the electrical load measurements are performed on the resistor (8 W or 4 W) in differential mode. 3. For Efficiency measurements, the optional 30 kHz filter is used. An RC low-pass filter is selected with (100 W, 47 nF) on each PWM output. http://onsemi.com 5 NCP2821 TYPICAL CHARACTERISTICS 100 90 DIE TEMPERATURE (C) 80 EFFICIENCY (%) 70 60 50 40 30 20 10 0 0 0.5 Pout (W) 1.0 Vp = 5 V RL = 8 W Class AB NCP2821 100 90 80 70 60 50 40 30 20 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 Pout (W) NCP2821 Vp = 5 V RL = 8 W Class AB Figure 3. Efficiency vs. Pout Vp = 5 V, RL = 8 W, f = 1 kHz 100 90 DIE TEMPERATURE (C) 80 EFFICIENCY (%) 70 60 50 40 30 20 10 0 0 0.1 0.2 0.3 0.4 Vp = 3.6 V RL = 8 W 0.5 0.6 0.7 Class AB NCP2821 60 55 50 45 40 35 30 25 20 0 Figure 4. Die Temperature vs. Pout Vp = 5 V, RL = 8 W, f = 1 kHz @ TA = +25C Class AB Vp = 3.6 V RL = 8 W NCP2821 0.1 0.2 0.3 0.4 0.5 0.6 0.7 Pout (W) Pout (W) Figure 5. Efficiency vs. P out Vp = 3.6 V, RL = 8 W, f = 1 kHz 90 80 70 EFFICIENCY % 60 50 40 30 20 10 0 0 0.5 1.0 Pout (W) 1.5 Vp = 5 V RL = 4 W 2.0 2.5 Class AB DIE TEMPERATURE (C) NCP2821 160 140 120 100 80 60 40 20 0 Figure 6. Die Temperature vs. P out Vp = 3.6 V, RL = 8 W, f = 1 kHz @ TA = +25C Class AB Vp = 5 V RL = 4 W NCP2821 0.5 1.0 Pout (W) 1.5 2.0 Figure 8. Efficiency vs. Pout Vp = 5 V, RL = 4 W, f = 1 kHz Figure 7. Die Temperature vs. Pout Vp = 5 V, RL = 4 W, f = 1 kHz @ TA = +25C http://onsemi.com 6 NCP2821 TYPICAL CHARACTERISTICS 90 80 70 EFFICIENCY % 60 50 40 30 20 10 0 0 0.2 0.4 0.6 Pout (W) 0.8 Class AB Vp = 3.6 V RL = 4 W DIE TEMPERATURE (C) NCP2821 100 90 80 70 60 50 40 NCP2821 30 20 1.0 1.2 0 0.2 0.4 0.6 Pout (W) 0.8 1.0 Vp = 3.6 V RL = 4 W Class AB Figure 9. Efficiency vs. Pout Vp = 3.6 V, RL = 4 W, f = 1 kHz 10 Vp = 5.0 V RL = 8 W f = 1 kHz THD+N (%) 10 Figure 10. Die Temperature vs. Pout Vp = 3.6 V, RL = 4 W, f = 1 kHz @ TA = +25C THD+N (%) 1.0 1.0 Vp = 4.2 V RL = 8 W f = 1 kHz 0.1 0.1 0.01 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 0.01 0 0.2 0.4 0.6 Pout (W) 0.8 1.0 1.2 Pout (W) Figure 11. THD+N vs. Pout Vp = 5 V, RL = 8 W, f = 1 kHz 10 Vp = 3.6 V RL = 8 W f = 1 kHz THD+N (%) 10 Figure 12. THD+N vs. Pout Vp = 4.2 V, RL = 8 W, f = 1 kHz THD+N (%) 1.0 1.0 Vp = 3 V RL = 8 W f = 1 kHz 0.1 0.1 0.01 0 0.2 0.4 Pout (W) 0.6 0.8 0.01 0 0.1 0.2 0.3 Pout (W) 0.4 0.5 0.6 Figure 13. THD+N vs. Pout Vp = 3.6 V, RL = 8 W, f = 1 kHz Figure 14. THD+N vs. Pout Vp = 3 V, RL = 8 W, f = 1 kHz http://onsemi.com 7 NCP2821 TYPICAL CHARACTERISTICS 10 Vp = 2.5 V RL = 8 W f = 1 kHz THD+N (%) 10 Vp = 5 V RL = 4 W f = 1 kHz 1.0 THD+N (%) 1.0 0.1 0.1 0.01 0 0.1 0.2 Pout (W) 0.3 0.4 0.01 0 0.5 1.0 1.5 Pout (W) 2.0 2.5 Figure 15. THD+N vs. Pout Vp = 2.5 V, RL = 8 W, f = 1 kHz 10 Vp = 4.2 V RL = 4 W f = 1 kHz THD+N (%) 10 Figure 16. THD+N vs. Pout Vp = 5 V, RL = 4 W, f = 1 kHz THD+N (%) 1.0 1.0 Vp = 3.6 V RL = 4 W f = 1 kHz 0.1 0.1 0.01 0 0.5 1.0 Pout (W) 1.5 2.0 0.01 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 Pout (W) Figure 17. THD+N vs. Pout Vp = 4.2 V, RL = 4 W, f = 1 kHz 10 Vp = 3 V RL = 4 W f = 1 kHz THD+N (%) THD+N (%) 10 Figure 18. THD+N vs. Pout Vp = 3.6 V, RL = 4 W, f = 1 kHz Vp = 2.5 V RL = 4 W f = 1 kHz 1.0 1.0 0.1 0 0.2 0.4 Pout (W) 0.6 0.8 1.0 0.1 0 0.1 0.2 0.3 Pout (W) 0.4 0.5 0.6 Figure 19. THD+N vs. Power Out Vp = 3 V, RL = 4 W, f = 1 kHz Figure 20. THD+N vs. Power Out Vp = 2.5 V, RL = 4 W, f = 1 kHz http://onsemi.com 8 NCP2821 TYPICAL CHARACTERISTICS 2.0 RL = 8 W f = 1 kHz 1.5 2.0 Pout (W) THD+N = 10% 1.0 THD+N = 1% 0.5 0.5 0 2.5 0 2.5 Pout (W) 1.5 1.0 THD+N = 1% THD+N = 10% 3.0 2.5 RL = 4 W f = 1 kHz 3.0 3.5 4.0 4.5 5.0 3.0 3.5 4.0 4.5 5.0 POWER SUPPLY (V) POWER SUPPLY (V) Figure 21. Output Power vs. Power Supply RL = 8 W @ f = 1 kHz 10 10 Figure 22. Output Power vs. Power Suppy RL = 4 W @ f = 1 kHz THD+N (%) THD+N (%) 1.0 Vp = 2.5 V 0.1 Vp = 3.6 V Vp = 5 V 1.0 Vp = 2.5 V 0.1 Vp = 5 V Vp = 3.6 V 0.01 10 100 1000 FREQUENCY (Hz) 10000 100000 0.01 10 100 1000 FREQUENCY (Hz) 10000 100000 Figure 23. THD+N vs. Frequency RL = 8 W, Pout = 250 mW @ f = 1 kHz -20 -30 -40 -50 -60 -70 -80 10 Vp = 5 V -20 -30 -40 -50 -60 Inputs to GND RL = 8 W 100 1000 FREQUENCY (Hz) 10000 100000 -70 -80 10 Figure 24. THD+N vs. Frequency RL = 4 W, Pout = 250 mW @ f = 1 kHz PSSR (dB) PSSR (dB) Vp = 5 V Vp = 3.6 V Vp = 3.6 V Inputs to GND RL = 4 W 100 1000 FREQUENCY (Hz) 10000 100000 Figure 25. PSRR vs. Frequency Inputs Grounded, RL = 8 W, Vripple = 200 mvpkpk Figure 26. PSRR vs. Frequency Inputs grounded, RL = 4 W, Vripple = 200 mVpkpk http://onsemi.com 9 NCP2821 TYPICAL CHARACTERISTICS -20 -30 -40 -50 -60 -70 -80 10 Vp = 3.6 V RL = 8 W QUIESCENT CURRENT (mA) 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 120 130 140 TEMPERATURE (C) 150 160 Thermal Shutdown Vp = 3.6 V RL = 8 W CMMR (dB) 100 1000 FREQUENCY (Hz) 10000 100000 Figure 27. PSRR vs. Frequency Vp = 3.6 V, RL = 8 W, Vic = 200 mvpkpk 900 QUIESCENT CURRENT (mA) SHUTDOWN CURRENT (nA) 800 700 600 500 400 300 200 100 0 2.5 3.5 4.5 5.5 RL = 8 W 2.8 2.6 2.4 2.2 2.0 1.8 1.6 1.4 1.2 Figure 28. Thermal Shutdown vs. Temperature Vp = 5 V, RL = 8 W, RL = 8 W 1.0 2.5 3.5 4.5 5.5 POWER SUPPLY (V) POWER SUPPLY (V) Figure 29. Shutdown Current vs. Power Supply RL = 8 W 1000 Vp = 3.6 V RL = 8 W NOISE (mVrms) NOISE (mVrms) 1000 Figure 30. Quiescent Current vs. Power Supply RL = 8 W Vp = 5 V RL = 8 W 100 No Weighting 100 No Weighting With A Weighting With A Weighting 10 10 100 1000 10000 10 10 100 1000 10000 FREQUENCY (Hz) FREQUENCY (Hz) Figure 31. Noise Floor, Inputs AC Grounded with 1 mF Vp = 3.6 V Figure 32. Noise Floor, Inputs AC Grounded with 1 mF Vp = 5 V http://onsemi.com 10 NCP2821 11 TA = +85C TURN OFF TIME (mS) TURN ON TIME (mS) 10 TA = +25C 9 TA = -40C 8 7 TA = +25C 6 TA = +85C TA = -40C 8 5 7 6 2.5 3.5 4.5 5.5 4 2.5 3.5 4.5 5.5 POWER SUPPLY (V) POWER SUPPLY (V) Figure 33. Turn on Time Figure 34. Turn off Time Turn on time Output differential voltage Output differential voltage Turn off time Shutdown signal 0 2 4 6 8 10 12 (ms) 14 16 18 20 0 1 2 3 4 5 6 (ms) 7 Shutdown signal 8 9 10 Figure 35. Turn on sequence Vp = 3.6 V, RL = 8 W Figure 36. Turn off sequence Vp = 3.6 V, RL = 8 W http://onsemi.com 11 NCP2821 DESCRIPTION INFORMATION Detailed Description The basic structure of the NCP2821 is composed of one analog pre-amplifier, a pulse width modulator and an H-bridge CMOS power stage. The first stage is externally configurable with gain-setting resistor Ri and the internal fixed feedback resistor Rf (the closed-loop gain is fixed by the ratios of these resistors) and the other stage is fixed. The load is driven differentially through two output stages. The differential PWM output signal is a digital image of the analog audio input signal. The human ear is a band pass filter regarding acoustic waveforms, the typical values of which are 20 Hz and 20 kHz. Thus, the user will hear only the amplified audio input signal within the frequency range. The switching frequency and its harmonics are fully filtered. The inductive parasitic element of the loudspeaker helps to guarantee a superior distortion value. Power Amplifier (5.0 ms). This method to turn on the device is optimized in terms of rejection of "pop and click" noises. Thus, the total turn on time to get full power to the load is 9 ms (typical) (see Figure 35). The device has the same behavior when it is turned-off by a logic low on the shutdown pin. No power is delivered to the load 5 ms after a falling edge on the shutdown pin (see Figure 36). Due to the fast turn on and off times, the shutdown signal can be used as a mute signal as well. Shutdown Function The device enters shutdown mode when the shutdown signal is low. During the shutdown mode, the DC quiescent current of the circuit does not exceed 1.5 mA. Current Breaker Circuit The output PMOS and NMOS transistors of the amplifier have been designed to deliver the output power of the specifications without clipping. The channel resistance (Ron) of the NMOS and PMOS transistors is typically 0.3 W. Turn On and Turn Off Transitions In order to eliminate "pop and click" noises during transition, the output power in the load must not be established or cutoff suddenly. When a logic high is applied to the shutdown pin, the internal biasing voltage rises quickly and, 4 ms later, once the output DC level is around the common mode voltage, the gain is established slowly The maximum output power of the circuit corresponds to an average current in the load of 820 mA. In order to limit the excessive power dissipation in the load if a short-circuit occurs, a current breaker cell shuts down the output stage. The current in the four output MOS transistors are real-time controlled, and if one current exceeds the threshold set to 1.5 A, the MOS transistor is opened and the current is reduced to zero. As soon as the short-circuit is removed, the circuit is able to deliver the expected output power. This patented structure protects the NCP2821. Since it completely turns off the load, it minimizes the risk of the chip overheating which could occur if a soft current limiting circuit was used. http://onsemi.com 12 NCP2821 APPLICATION INFORMATION NCP2821 PWM Modulation Scheme The NCP2821 uses a PWM modulation scheme with each output switching from 0 to the supply voltage. If Vin = 0 V outputs OUTM and OUTP are in phase and no current is flowing through the differential load. When a positive signal is applied, OUTP duty cycle is greater than 50% and OUTM is less than 50%. With this configuration, the current through the load is 0 A most of the switching period and thus power losses in the load are lowered. OUTP OUTM +Vp 0V -Vp Load Current 0A Figure 37. Output Voltage and Current Waveforms into an Inductive Loudspeaker DC Output Positive Voltage Configuration Voltage Gain Optional Output Filter The first stage is an analog amplifier. The second stage is a comparator: the output of the first stage is compared with a periodic ramp signal. The output comparator gives a pulse width modulation signal (PWM). The third and last stage is the direct conversion of the PWM signal with MOS transistors H-bridge into a powerful output signal with low impedance capability. With an 8 W load, the total gain of the device is typically set to: - 12 dB if a low level is applied to the GS pin - 6 dB if a high level is applied to the GS pin Input Capacitor Selection (Cin) The input coupling capacitor blocks the DC voltage at the amplifier input terminal. This capacitor creates a high-pass filter with Rin, the cut-off frequency is given by Fc + 2 p 1 Ri Ci . When a 6 dB gain is chosen the internal impedance is set to 150 kW. With a 12 dB gain, the internal resistance is 75 kW and thus an input capacitor value between 10 nF and 1 mF will give a cutoff frequency between 1 Hz and 212 Hz. The NCP2821 also includes a built in low pass filtering function. Its cutoff frequency is set to 20 kHz. This filter is optional due to the capability of the speaker to filter by itself the high frequency signal. Nevertheless, the high frequency is not audible and filtered by the human ear. An optional filter can be used for filtering high frequency signal before the speaker. In this case, the circuit consists of two inductors (15 mH) and two capacitors (2.2 mF) (Figure 38). The size of the inductors is linked to the output power requested by the application. A simplified version of this filter requires a 1 mF capacitor in parallel with the load, instead of two 2.2 mF connected to ground (Figure 39). Cellular phones and portable electronic devices are great applications for Filterless Class-D as the track length between the amplifier and the speaker is short, thus, there is usually no need for an EMI filter. However, to lower radiated emissions as much as possible when used in filterless mode, a ferrite filter can often be used. Select a ferrite bead with the high impedance around 100 MHz and a very low DCR value in the audio frequency range is the best choice. The MPZ1608S221A1 from TDK is a good choice. The package size is 0603. http://onsemi.com 13 NCP2821 OUTM 15 mH OUTM 2.2 mF RL = 8 W 1.0 mF OUTP 15 mH 15 mH 15 mH RL = 8 W 2.2 mF OUTP Figure 38. Advanced Optional Audio Output Filter Figure 39. Optional Audio Output Filter OUTM RL = 8 W FERRITE CHIP BEADS OUTP Figure 40. Optional EMI Ferrite Bead Filter Cs VP Differential Audio Input from DAC INP INM OUTM Input from Microcontroller SD OUTP GND Figure 41. NCP2821 Application Schematic with Fully Differential Input Configuration Cs VP Differential Audio Input from DAC INP INM FERRITE CHIP BEADS Input from Microcontroller SD OUTP OUTM GND Figure 42. NCP2821 Application Schematic with Fully Differential Input Configuration and Ferrite Chip Beads as an Output EMI Filter http://onsemi.com 14 NCP2821 Cs Ci Differential Audio Input from DAC Ci Input from Microcontroller SD INP INM VP OUTM FERRITE CHIP BEADS OUTP GND Figure 43. NCP2821 Application Schematic with Differential Input Configuration and High Pass Filtering Function Cs Ci INP Single-Ended Audio Input from DAC Input from Microcontroller INM Ci SD OUTP VP OUTM GND Figure 44. NCP2821 Application Schematic with Single Ended Input Configuration http://onsemi.com 15 NCP2821 Vp J1 U1 Rf C1 100 nF J2 GS INM Ri Vp C4 4.7 mF J7 BYP RAMP GENERATOR Gain Control GS Data Processor OUTP J3 RL = 8 W OUTM GND J4 *J6, J10 Not Mounted C2 100 nF J8 INP Ri BYP Rf 300 kW SD Vp J9 J10* J9 CL = 12 dB CL = 6 dB J6* J5 CL = NCP2821 OFF J5 Vp CL = NCP2821 ON Shutdown Control Figure 45. Schematic of the Demonstration Board of the 9-pin Flip-Chip CSP Device Figure 46. Silkscreen Layer http://onsemi.com 16 NCP2821 PCB Layout Information NCP2821 is suitable for low cost solution. In a very small package it gives all the advantages of a Class-D audio amplifier. The required application board is focused on low cost solution too. Due to its fully differential capability, the audio signal can only be provided by an input resistor. If a low pass filtering function is required, then an input coupling capacitor is needed. The values of these components determine the voltage gain and the bandwidth frequency. The battery positive supply voltage requires a good decoupling capacitor versus the expected distortion. When the board is using Ground and Power planes with at least 4 layers, a single 4.7 mF filtering ceramic capactior on the bottom face will give optimized performance. A 1.0 mF low ESR ceramic capacitor can also be used with slightly degraded performances on the THD+N from 0.06% up to 0.2%. In a two layers application, if both Vp pins are connected on the top layer, a single 4.7 mF decoupling capacitor will optimize the THD+N level. The NCP2821 power audio amplifier can operate from 2.5 V until 5.5 V power supply. With less than 2% THD+N, it delivers 500 mW rms output power to a 8.0 W load at Vp =3.0 V and 1.0 W rms output power at Vp = 4.0 V. Note Figure 47. Top Layer Note: This track between Vp pins is only needed when a 2 layers board is used. In case of a typical 4 or more layers, the use of laser vias in pad will optimize the THD+N floor. The demonstration board delivered by ON Semiconductor is a 4 Layers with Top, Ground, Power Supply and Bottom. http://onsemi.com 17 NCP2821 Bill of Materials Item 1 2 3 4 5 6 7 8 Part Description NCP2821 Audio Amplifier Ceramic Capacitor 100 nF, 50 V, X7R Ceramic Capacitor 4.7 mF, 6.3 V, X5R PCB Footprint I/O connector. It can be plugged by MC-1,5/3-ST-3,81 I/O connector. It can be plugged by BLZ5.08/2 (Weidmuller Reference) Jumper Connector, 400 mils Jumper Header Vertical Mount 3*1, 2.54 mm. Ref U1 C1, C2 C4 J7, J8 J2 J1, J3 J4 J5, J9 Phoenix Contact Weidmuller Harwin Tyco Electronics / AMP MC-1,5/3-G SL5.08/2/90B D3082-B01 5-826629-0 0603 0603 TDK TDK PCB Footprint Manufacturer Part Number NCP2821 C1608X7R1H104KT C1608X5R0J475MT ORDERING INFORMATION Device NCP2821FCT1G Marking MAU Package 9-Pin Flip-Chip CSP (Pb-Free) Shipping 3000 / Tape & Reel For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specifications Brochure, BRD8011/D. http://onsemi.com 18 NCP2821 PACKAGE DIMENSIONS 9-PIN FLIP-CHIP CSP FC SUFFIX CASE 499AL-01 ISSUE O 4X -A- D -B- E 0.10 C NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: MILLIMETERS. 3. COPLANARITY APPLIES TO SPHERICAL CROWNS OF SOLDER BALLS. MILLIMETERS MIN MAX 0.540 0.660 0.210 0.270 0.330 0.390 1.450 BSC 1.450 BSC 0.290 0.340 0.500 BSC 1.000 BSC 1.000 BSC TOP VIEW 0.10 C 0.05 C -C- SEATING PLANE A DIM A A1 A2 D E b e D1 E1 A2 A1 SIDE VIEW D1 e C B e A 9X E1 b 1 2 3 0.05 C A B 0.03 C BOTTOM VIEW ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. "Typical" parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including "Typicals" must be validated for each customer application by customer's technical experts. SCILLC does not convey any license under its patent rights nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner. PUBLICATION ORDERING INFORMATION LITERATURE FULFILLMENT: N. American Technical Support: 800-282-9855 Toll Free Literature Distribution Center for ON Semiconductor USA/Canada P.O. Box 61312, Phoenix, Arizona 85082-1312 USA Phone: 480-829-7710 or 800-344-3860 Toll Free USA/Canada Japan: ON Semiconductor, Japan Customer Focus Center 2-9-1 Kamimeguro, Meguro-ku, Tokyo, Japan 153-0051 Fax: 480-829-7709 or 800-344-3867 Toll Free USA/Canada Phone: 81-3-5773-3850 Email: orderlit@onsemi.com ON Semiconductor Website: http://onsemi.com Order Literature: http://www.onsemi.com/litorder For additional information, please contact your local Sales Representative. http://onsemi.com 19 NCP2821/D |
Price & Availability of NCP2821
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