EUA4890 1 Watt Audio Power Amplifier DESCRIPTION FEATURES The EUA4890 is an audio power amplifier designed for portable communication device applications such as mobile phone applications. The EUA4890 is capable of delivering 1.0W of continuous average power to an 8Ω BTL and with less than 1% distortion (THD+N) from a 5.0V power supply, and 350mW to a 8Ω BTL load from a 3V power supply. The EUA4890 provides high quality audio while requiring few external components and minimal power consumption. It features a low-power shutdown mode, which is achieved by driving the SHUTDOWN pin with logic low. The EUA4890 contains circuitry to prevent from ”pop and click” noise that would otherwise occur during turn-on and turn-off transitions. For maximum flexibility, the EUA4890 provides an externally controlled gain (with resistors), as well as an externally controlled turn-on and turn-off times (with the bypass capacitor). z z z z z z z z z z RoHS compliant and 100% lead(Pb)-free APPLICATIONS z z z The EUA4890 is available in a MSOP-8 , 3mm×3mm DFN package. Block Diagram Figure1. DS4890 Ver 1.7 Dec. 2006 2.5-5.5V operation 65dB PSRR at 217Hz, VDD=5V 0.1µA ultra low current shutdown mode Improved pop & click circuitry No output coupling capacitors, snubber networks or bootstrap capacitors required Thermal shutdown protection Unity-gain stable External gain configuration capability BTL output can drive capacitive loads 1 Mobile Phones PDAs Portable electronic devices EUA4890 Typical Application Circuit Figure2. Audio Amplifier with Single –Ended Input Figure3. Audio Amplifier with Differential Input DS4890 Ver 1.7 Dec. 2006 2 EUA4890 Pin Configurations Package Type Package Type Pin Configurations Top View Pin Configurations Top View DFN-8 MSOP-8 Pin Description PIN PIN I/O SHUTDOWN 1 I The device enters in shutdown mode when a low level is applied on this pin BYPASS 2 I Bypass capacitor pin which provides the common mode voltage +IN 3 I -IN 4 I VO1 5 O VDD 6 I Positive input of the first amplifier, receives the common mode voltage Negative input of the first amplifier, receives the audio input signal. Connected to the feedback resistor Rf and to the input resistor Rin. Negative output of the EUA4890. Connected to the load and to the feedback resistor Rf Analog VDD input supply. GND 7 VO2 8 DS4890 Ver 1.7 Dec. 2006 DESCRIPTION Ground connection for circuitry. O Positive output of the EUA4890. 3 EUA4890 Ordering Information Order Number Package Type EUA4890MIR1 MSOP-8 EUA4890JIR1 DFN-8 EUA4890 Marking xxxx A4890 xxxx A4890 □ □ □ □ Lead Free Code 1: Lead Free 0: Lead Packing R: Tape & Reel Operating temperature range I: Industry Standard Package Type J: DFN M: MSOP DS4890 Ver 1.7 Dec. 2006 4 Operating Temperature range -40 °C to 85°C -40 °C to 85°C EUA4890 Absolute Maximum Ratings Supply voltage, VDD ▓ Input voltage, VI ---------------------------------------------------------------------------- ▓ ESD Susceptibility ▓ -65°C to 150°C -------------------------------------------------------------------------------------------- Junction Temperature ▓ 6V -0.3 V to VDD +0.3V Storage temperature rang, Tstg ------------------------------------------------------------------- ▓ ▓ -------------------------------------------------------------------------------------------- -------------------------------------------------------------------------------------- 2kV 150°C Thermal Resistance θJC (MSOP) --------------------------------------------------------------------------------------------- 56°C/W θJA (MSOP) ---------------------------------------------------------------------------------------------- 160°C/W θJA (DFN) ---------------------------------------------------------------------------------------------- 50°C/W Electrical Characteristics VDD = 5V, TA = 25°C Symbol Parameter IDD Quiescent Power Supply Current ISD Shutdown Current VSDIH Shutdown Voltage Input High VSDIL Shutdown Voltage Input Low VOS Conditions TWU Wake-up time TSD Thermal Shutdown Temperature THD+N Total Harmonic Distortion + Noise PSRR TSDT 5 mA VIN=0V, IO=0A, 8Ω load 2.5 5 mA VSHUTDOWN=0V 0.1 2.0 µA 1.2 7.0 THD=1%; f=1kHz V 0.4 V 5 25 mV 8.5 9.7 kΩ 1.1 170 150 PO=0.4 Wrms; f=1kHz Power Supply Rejection Ratio Vripple=200mV sine p-p Input Terminated with 10 ohms to ground Shutdown Time 8Ω load DS4890 Ver 1.7 Dec. 2006 Unit 2.4 Output Offset Voltage Output Power (8Ω) EUA4890 Typ Max. VIN=0V, IO=0A, No load ROUT-GND Resistor Output to GND PO Min 5 55 W 220 ms 170 °C 0.15 % 65(f=217 Hz) 67(f=1kH z) dB 1.0 ms EUA4890 Electrical Characteristics VDD = 3V, TA = 25°C Symbol Parameter IDD Quiescent Power Supply Current ISD Shutdown Current VSDIH Shutdown Voltage Input High VSDIL VOS Shutdown Voltage Input Low Output Offset Voltage Conditions Output Power (8Ω) Wake-up time Thermal Shutdown Temperature THD+N Total Harmonic Distortion + Noise PSRR Power Supply Rejection Ratio EUA4890 Typ Max. Unit VIN=0V, IO=0A, No load 1.8 4 mA VIN=0V, IO=0A, 8Ω load VSHUTDOWN=0V 1.9 0.1 4 2.0 mA µA 1.2 ROUT-GND Resistor Output to GND PO TWU TSD Min THD=1%; f=1kHz 5 0.4 25 V mV 7.0 8.5 9.7 kΩ 0.28 0.35 120 170 180 W ms °C 150 PO=0.15 Wrms; f=1kHz Vripple=200mV sine p-p Input Terminated with 10 ohms to ground V 45 0.15 65(f=217 Hz) 66(f=1kH z) % dB Electrical Characteristics VDD = 2.6V, TA = 25°C Symbol Parameter Conditions Min EUA4890 Typ Max. Unit IDD Quiescent Power Supply Current VIN=0V, IO=0A, No load 1.7 mA ISD Shutdown Current Output Power (8Ω) Output Power (4Ω) VSHUTDOWN=0V THD=1%; f=1kHz THD=1%; f=1kHz 0.1 0.25 0.32 µA 0.15 55(f=217 Hz) 56(f=1kH z) % PO THD+N Total Harmonic Distortion + Noise PSRR Power Supply Rejection Ratio DS4890 Ver 1.7 Dec. 2006 PO=0.1Wrms; f=1kHz Vripple=200mV sine p-p Input Terminated with 10 ohms to ground 6 W dB EUA4890 Typical Operating Characteristics Figure3. Figure4. Figure5. Figure6. Figure7. Figure8. DS4890 Ver 1.7 Dec. 2006 7 EUA4890 Figure9. Figure10. Figure11. Figure12. Figure14. Figure13. DS4890 Ver 1.7 Dec. 2006 8 EUA4890 Figure15. Figure16. Figue18. Figure17. Figure20. Figure19. DS4890 Ver 1.7 Dec. 2006 9 EUA4890 Figure21. Figure22. Figure23. Figure24. Figure26. Figure25. DS4890 Ver 1.7 Dec. 2006 10 EUA4890 Figure27. Figure28. Figure30. Figure29. Figure31. DS4890 Ver 1.7 Dec. 2006 11 EUA4890 Application Information Bridged Configuration Explanation The structure of the EUA4890 is basically composed of two identical internal power amplifiers; the first one si externally configurable with gain-setting resistors Rin and Rf (the closed-loop gain is fixed by the ratios of theses resistors) and the second is internally fixed in an inverting unity-gain configuration by two resistors of 20kΩ. So the load is driven differentially through OUTA and OUTB outputs. This configuration eliminates the need for an output coupling capacitor. The differential-ended amplifier presents two major advantages: - The possible output power is four times larger (the output swing is doubled) as compared to single-ended amplifier under the same conditions. - Output pins (OUTA and OUTB) are biased at the same potential VDD/2, this eliminates the need for an output coupling capacitor required with a single-ended amplifier configuration. The differential closed loop-gain of the amplifier is given by Avd= 2× R f = Vorms R Vinrms in Power Dissipation Power dissipation is a major concern when designing a successful amplifier, whether the amplifier is bridged or single-ended. A direct consequence of the increased power delivered to the load by a bridge amplifier is an increase in internal power dissipation. Since the EUA4890 has two operational amplifiers in one package, the maximum internal power dissipation is 4 times that of a single-ended amplifier. The maximum power dissipation for a given application can be derived from the power dissipation graphs of from equation1. PDMAX = 4 * (VDD ) 2 /(2π 2 R L ) ------------(1) It is critical that the maximum junction temperature TJMAX of 150°C is not exceeded. TJMAX can be determine from the power derating curves by using PDMAX and the PC board foil area. By adding additional copper foil, the thermal resistance of the application can be reduced, resulting in higher PDMAX. Additional copper foil can be added to any of the leads connected to the EUA4890.If TJMAX still exceeds 150°C, then additional changes must be made. These changes can include reduced supply voltage, higher load impedance, or reduced ambient temperature. Internal power dissipation is a function of output power. DS4890 Ver 1.7 Dec. 2006 Proper Selection of External Components The EUA4890 is unity-gain stable and requires no external components besides gain-setting resistors, and input coupling capacitor and proper bypassing capacitor in the typical application. Gain-Setting Resistor Selection (Rin and Rf) Rin and Rf set the closed-loop gain of the amplifier. In order to optimize device and system performance, the EUA4890 should be used in low gain configurations. The low gain configuration minimizes THD + noise values and maximizes the signal to noise ratio, and the amplifier can still be used without running into the bandwidth limitations. Low gain configurations require large input signals to obtain a given output power. Input signals equal to or greater than 1Vrms are available from sources such as audio codecs. A closed loop gain in the range from 2 to 5 is recommended to optimize overall system performance. An input resistor (Rin) value of 20kΩ is realistic in most of applications, and does not require the use of a too large capacitor Cin. 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 = 1 2 * ∏ *R in *C in The size of the capacitor must be large enough to couple in low frequencies without severe attenuation. However a large input coupling capacitor requires more time to reach its quiescent DC voltage (VDD/2) and can increase the turn-on pops. An input capacitor value between 0.1µ and 0.39µF performs well in many applications (with Rin=22kΩ). Bypass Capacitor Selection (Cby) The bypass capacitor Cby provides half-supply filtering and determines how fast the EUA4890 turns on. This capacitor is critical component to minimize the turn-on pop. A 1.0µF bypass capacitor value (Cin= ＜ 0.39µF) should produce clickless and popless shutdown transitions. The amplifier is still functional with a 0.1µF capacitor value but is more susceptible to pop and click noise. Thus, a 1.0µF bypassing capacitor is recommended. Power Supply Bypassing (CS) As with any amplifier, proper supply bypassing is critical for low noise performance and high power supply rejection. The capacitor location on both the bypass and power supply pins should be as close to the device is possible. 12 EUA4890 Packaging Information MSOP-8 SYMBOLS A A1 D E1 E L b e DS4890 Ver 1.7 Dec. 2006 MILLIMETERS MIN. MAX. 1.10 0.00 0.15 3.00 3.00 4.70 5.10 0.40 0.80 0.22 0.38 0.65 13 INCHES MIN. 0.000 MAX. 0.043 0.006 0.118 0.118 0.185 0.016 0.008 0.201 0.031 0.015 0.026 EUA4890 DFN-8 SYMBOLS A A1 b D D1 E E1 e L DS4890 Ver 1.7 Dec. 2006 MILLIMETERS MIN. MAX. 0.70 0.90 0.00 0.05 0.20 0.40 2.85 3.15 2.30 2.85 3.15 1.50 0.65 0.25 0.45 14 INCHES MIN. 0.028 0.000 0.008 0.112 MAX. 0.035 0.002 0.016 0.124 0.090 0.112 0.124 0.059 0.026 0.010 0.018