LX1792 I N T E G R A T E D Low Voltage, Low Power, AudioMite™ Class-D Audio Amplifier P R O D U C T S P RELIMINARY S PECIFICATION KEY FEATURES DESCRIPTION The LX1790 consists of a preamplifier followed by a fixed gain class D amplifier. The input resistor and feedback resistor is external in the LX1792 making it possible to set the gain arbitrarily, up to approximately 40dB. The feedback resistor can also be potentiometer to facilitate volume control. ! Low Operating Current: 120µA Typical ! Low Operating Voltage: 0.9V minimum ! Gain set by external resistors ! 3 Output Switch Resistance Settings: 48, 24 & 16 Ω ! 5uVrms input referred noise. APPLICATIONS ! Hearing Aid applications ! High impedance speaker /Transducer applications IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com W W W. Microsemi .COM The MSC-LX1792 offers a patent pending, low voltage, low power, and high efficiency amplifier for driving a high impedance speaker such as a hearing aid receiver. The core of the amplifier is built upon Microsemi’s patented LX1790 class D amplifier. PRODUCT HIGHLIGHT CLOCK DIN PRE AMP Σ CMP HBRIDGE SPEAKER TJ (°°C) 10 to 55 Copyright 2001 Rev. 0.3,2002-05-08 J LM Plastic MLPM 8-Pin LX1792CLM Plastic MSOP 8-Pin LX1792CDU DU Microsemi INTEGRATED PRODUCTS 5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541 BD LX1792 PACKAGE ORDER INFO Ceramic Dip 14-Pin LX1792CJ Bare Die LX1792BD Page 1 LX1792 I N T E G R A T E D Low Voltage, Low Power, AudioMite™ Class-D Audio Amplifier P R O D U C T S P RELIMINARY S PECIFICATION PACKAGE PIN OUT Input Logic Supply Voltage (VDD).......................................-0.3V to +3.0V Operating Temperature Range ................................................10°C to 55°C Note: Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground. Currents are positive into, negative out of specified terminal. VSS 1 8 VDD OUTN 2 7 OUTP IMPSEL 3 6 PREOUT 4 5 IN W W W. Microsemi .COM ABSOLUTE MAXIMUM RATINGS LM PACKAGE (Top View) SETTINGS PIN IMPSEL=VSS IMPSEL=VDD IMPSEL=Floating IMPSEL 16Ω 24Ω 48Ω VSS 1 8 VDD OUTN 2 7 OUTP IMPSEL 3 6 PREOUT 4 5 IN DU PACKAGE (Top View) OUTN 1 14 OUTP VSS 2 1 13 VDD 3 12 4 11 5 10 6 9 PREOUT 7 8 IN IMPSEL J PACKAGE (Top View) FUNCTIONAL PIN DESCRIPTION PIN NAME PIN NO 14 PIN J PIN NO 8 PIN DU DESCRIPTION VDD 13 8 8 Supply Voltage VSS 2 1 1 Ground IN 8 5 5 Analog Audio Input OUTP 14 7 7 Positive Output Voltage OUTN 1 2 2 Negative Output Voltage PREOUT 9 6 6 Pre amplifier output IMPSEL 6 3 3 Output Resistance Select. See Settings table below for selections. Copyright 2001 Rev. 0.3,2002-05-08 Microsemi INTEGRATED PRODUCTS 5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541 PACKAGE DATA (EVALUATION SAMPLES) PIN NO 8 PIN LM Page 2 LX1792 I N T E G R A T E D P R O D U C T S Low Voltage, Low Power, AudioMite™ Class-D Audio Amplifier P RELIMINARY S PECIFICATION Parameter ! Symbol Test Conditions Min LX1792 Typ Max Units OPERATING CONDITIONS Supply Voltage VDD Ground VSS 0.9 1.5 0 V V ELECTRICAL CHARACTERISTICS Unless otherwise specified, the following specifications apply over the operating ambient temperature TA=25°C except where otherwise noted. Test conditions: VDD=1.3V, VSS=0V, Circuit connected as application schematic on page 5,Output loaded with 200Ohm in series with 60mH. Parameter Symbol Switch Output Resistance @ Low Drive Switch Output Resistance @ Med Drive Switch Output Resistance @ High Drive Test Conditions Min LX1792 Typ ROUT-L 48 ROUT-M 24 ROUT-HI 16 Quiescent Current @ Low Drive IDDQL 110 Quiescent Current @ Med Drive IDDQM Quiescent Current @ High Drive IDDQH 3dB Bandwidth – min Frequency FMIN 3dB Bandwidth – max Frequency FMAX Output Switching Frequency Gain1 A1 Power Supply Rejection Ratio PSRR Total Harmonic Distortion THD1 Input Referred Noise VN-20 Output clock frequency FCLK Max absolute DC Offset OutN-OutP VOFF-NP No load Max W W W. Microsemi .COM RECOMMENDED OPERATING CONDITIONS Units Ω 19 µA 120 130 40 R1=50k, R2=1000k, Fin=1kHz 100 10 Hz KHz FCLK 200 KHz R1=50k, R2=500k R1=25k, R2=500k Input Reference R1=50k, R2=500k R1=50k, R2=500k, Vin=5mVrms, Fin=1kHz R1=25k, R2=500k, Vin=5mVrms, Fin=1kHz R1=50k, R2=500k, 100Hz-10kHz, No weighting R1=25k, R2=500k, 100Hz-10kHz, No weighting 32 37 dB 45 dB No input signal 0.3 0.5 4 3 % µVrms 140 200 300 KHz 0 0.5 5 mV () ELECTRICALS Copyright 2001 Rev. 0.3,2002-05-08 Microsemi INTEGRATED PRODUCTS 5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541 Page 3 LX1792 I N T E G R A T E D P R O D U C T S Low Voltage, Low Power, AudioMite™ Class-D Audio Amplifier P RELIMINARY S PECIFICATION CHARTS W W W. Microsemi .COM Note: Graphs show distortion with no load outputs CHARTS Copyright 2001 Rev. 0.3,2002-05-08 Microsemi INTEGRATED PRODUCTS 5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541 Page 4 LX1792 I N T E G R A T E D Low Voltage, Low Power, AudioMite™ Class-D Audio Amplifier P R O D U C T S P RELIMINARY S PECIFICATION W W W. Microsemi .COM CHARTS (CONTINUED) LX1790 H-bridge on impedance 30 Ron [Ohm] 25 20 15 10 5 0 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5 1.6 Supply voltage Figure 2 – H-Bridge Impedance vs. Supply Voltage (Lowest Impedance Setting) CHARTS Copyright 2001 Rev. 0.3,2002-05-08 Microsemi INTEGRATED PRODUCTS 5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541 Page 5 LX1792 I N T E G R A T E D P R O D U C T S Low Voltage, Low Power, AudioMite™ Class-D Audio Amplifier P RELIMINARY S PECIFICATION W W W. Microsemi .COM APPLICATION SCHEMATIC Transducer/Speaker C2 Battery 0.9-1.5 V IMPsel NC Volume cntrl potentiometer OUTP PREOUT R2 CIN OUTN VDD MSC-LX1792 VSS R1 IN Microphone SUGGESTED EXTERNAL APPLICATION COMPONENTS Component Suggested value CIN 100nF C2 R1 R2 RX/CX Description Input AC coupling capacitor, must be present For best performance this should be as close as possible to the supply pins > 25k Ohm Input resistor > 25k Ohms Preamplifier feedback resistor If the audio source (for example a microphone) has a low power supply rejection an additional filter for the supply to this have to be added. APPLICATION Copyright 2001 Rev. 0.3,2002-05-08 Microsemi INTEGRATED PRODUCTS 5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541 Page 6 LX1792 I N T E G R A T E D Low Voltage, Low Power, AudioMite™ Class-D Audio Amplifier P R O D U C T S P RELIMINARY S PECIFICATION LM 8-Pin Plastic MLP-Micro Exposed Pad Dim A A B C D E F G H I J K K J E B H I G C F INCHES MIN MAX 0.114 0.122 0.114 0.122 0.025 0.029 0.005 0.009 0.075 BSC 0.010 0.016 0.025 BSC 0.048 BSC 0 0.003 0.008 0.014 0 0.003 14-Pin Ceramic Dip A Dim 1 L C F K G D J MILLIMETERS MIN MAX 19.30 19.94 5.59 7.11 5.08 0.38 0.51 1.02 1.77 2.54 BSC 2.03 0.20 0.38 3.18 5.08 7.37 7.87 15° INCHES MIN MAX 0.760 0.785 0.220 0.280 0.200 0.015 0.020 0.040 0.070 0.100 BSC 0.080 0.008 0.015 0.125 0.200 0.290 0.310 15° MECHANICAL A B C D F G H J K L M B H MILLIMETERS MIN MAX 2.90 3.10 2.90 3.10 0.65 0.75 0.15 0.25 1.841 BSC 0.27 0.43 0.65 BSC 1.22 BSC 0 0.10 0.21 0.37 0 0.10 Internally Connected together, but isolated from all other terminals D J W W W. Microsemi .COM MECHANICAL – 8 PIN MLPQ PACKAGE OUTLINE M Note: 1. Dimensions do not include mold flash or protrusions; these shall not exceed 0.155mm(.006”) on any side. Lead dimension shall not include solder coverage. Copyright 2001 Rev. 0.3,2002-05-08 Microsemi INTEGRATED PRODUCTS 5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541 Page 7 LX1792 I N T E G R A T E D Low Voltage, Low Power, AudioMite™ Class-D Audio Amplifier P R O D U C T S P RELIMINARY S PECIFICATION MECHANICALS 8-Pin MSOP MILLIMETERS MIN MAX 2.85 3.05 2.90 3.10 – 1.10 0.25 0.40 0.65 BSC 0.38 0.64 0.13 0.18 0.95 BSC 0.40 0.70 3° 0.05 0.15 4.75 5.05 Dim A B H G P M C N W W W. Microsemi .COM DU 7-PIN BARE DIE D L A B C D G H J K L M N P INCHES MIN MAX .112 .120 .114 .122 – 0.043 0.009 0.160 0.025 BSC 0.015 0.025 0.005 0.007 0.037 BSC 0.016 0.027 3° 0.002 0.006 0.187 0.198 K Dim X Y MILLIMETERS MIN MAX 1.15 1.78 INCHES MIN MAX 0.045 0.070 Note: 1. Dimensions do not include mold flash or protrusions; these shall not exceed 0.155mm(.006”) on any side. Lead dimension shall not include solder coverage. MECHANICAL Copyright 2001 Rev. 0.3,2002-05-08 Microsemi INTEGRATED PRODUCTS 5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541 Page 8 LX1792 I N T E G R A T E D P R O D U C T S Low Voltage, Low Power, AudioMite™ Class-D Audio Amplifier P RELIMINARY S PECIFICATION NOTES W W W. Microsemi .COM NOTES Preliminary Data – Information contained in this document is pre-production data and is proprietary to Microsemi. It may not be modified in any way without the express written consent of Microsemi. Product referred to herein is offered in sample form only and Microsemi reserves the right to change or discontinue this proposed product at any time. Copyright 2001 Rev. 0.3,2002-05-08 Microsemi INTEGRATED PRODUCTS 5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541 Page 9