tai'mec Preliminary www.taimec.com.tw / www.class-d.com.tw TMPA2155DM Rev.1.0 December 24, 2007 2.7-W MONO CLASS-D AUDIO POWER AMPLIFIER GENERAL DESCRIPTION FEATURES ♦ 2.5V to 6V Single Supply The TMPA2155DM is a mono class-D audio power amplifier IC. With BTL(Bridge-Tied-Load) configuration, it delivers up to ♦ Up to 2.7W at 5V, 3 ohms 2.7W power into a 3 ohms load or 2.3W power into a 4 ohm load ♦ Up to 85% Power Efficiency or 1.5W power into an 8 ohm load. No external heat-sink is ♦ Automatic output power control (APC) required. ♦ 2.2mA Quiescent Current at 5V For multiple-input applications, independent gain control and ♦ Less Than 0.2uA Shutdown Current corner frequency can be implemented by summing the input ♦ Pop-less Power-Up, Shutdown and Recovery sources through resistor ratio and input capacitor values. Automatic voltage gain control makes the best use of battery. ♦ Differential 250 KHz PWM Allows BTL to Doubles Output Power and Eliminates LC Output Filter Analog input signal is converted into digital output which drives ♦ Compatible with earphone application directly to the speaker. High power efficiency is achieved due to ♦ Thermal Shutoff and Automatic Recovery digital output at the load. The audio information is embedded in ♦ Short-Circuit Protection PWM（Pulse Width Modulation）. ♦ Differential Signal Processing Improves CMRR APPLICATIONS Package Multimedia application includes Cellular Phones, PDAs, TSSOP8, SOP8 Available, pb free【RoHS】 DVD/CD players, TFT LCD TVs/Monitors, 2.1 channel/5.1 channel audio systems, USB audio. It is also ideal for other For best performance, please refer to portable devices like Wireless Radios. http://www.taimec.com.tw/English/EVM.htm http://www.class-d.com.tw/English/EVM.htm for PCB layout. REFERENCE CIRCUIT Copyright ©2005, Tai-1 Microelectronics Corp. 1 tai'mec TMPA2155DM Preliminary www.taimec.com.tw / www.class-d.com.tw Rev.1.0 December 24, 2007 TOP VIEW （Please email [email protected] for complete datasheet.） Tai-1 Microelectronics reserves the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers are responsible for their products and applications using Tai-1 Microelectronics components. Note that the external components or PCB layout should be designed not to generate abnormal voltages to the chip to prevent from latch up which may cause damage to the device. Typical Application C3 1uF(6.3V)VDDA C7 VDD 470uF(6.3V) + C4 1uF(6.3V) L1 R1 0 R2 100 JP1 J1 IN1+ IN1- VO+ C5 1uF(6.3V) VO- C6 1uF(6.3V) 33uH C1 C2 1uF(6.3V) 1uF(6.3V) R4 R5 Ri Ri C9 470pF(6.3V) PHONEJACK STEREO 1 2 3 4 VO+ GND IN+ IN- Vo- 8 VDD7 VDDA 6 SDNB 5 L2 R3 SDNB 33uH 100 R6 10K S1 switch 2155DM C8 1uF(6.3V) ABSOLUTE MAXIMUM RATINGS Over operating free-air temperature range unless otherwise noted(1) Supply voltage, VDD Input voltage, VI Continuous total power dissipation Operating free-air temperature, TA In normal mode -0.3V to 6V V In shutdown mode -0.3V to 7V V -0.3V to VDD+0.3V V See package dissipation ratings 。C -20 to 85 Operating junction temperature, TJ -20 to 150 Storage temperature, Tstg -40 to 150 。C 。C (1) Stresses beyond those listed under”absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions “is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. Copyright ©2005, Tai-1 Microelectronics Corp. 2 tai'mec TMPA2155DM Preliminary www.taimec.com.tw / www.class-d.com.tw Rev.1.0 December 24, 2007 RECOMMENDED OPERATING CONDITONS MIN Supply voltage, VDD NOM MAX UNIT 2.5 6 V High-level input voltage, VIH SDNB 2 VDD V Low-level input voltage, VIL SDNB 0 0.8 V -20 85 。C Operating free-air temperature, TA PACKAGE DISSIPATION RATINGS PACKAGE SOP8 DERATING TA ≤ 25。C TA = 70。C TA = 85。C FACTOR POWER RATING POWER RATING POWER RATING 6.39mW/。C 0.799W 0.511W 0.415W ELECTRICAL CHARACTERISTICS TA=25。C (unless otherwise noted) PARAMETER │VOS│ PSRR Output offset voltage TEST CONDITIONS (measured differentially) Power supply rejection ratio MIN TYP MAX UNIT VI=0V,AV=2, VDD=VDDA=2.5V to 5.5V 25 VDD=VDDA=2.5V to 5.5V -75 -55 dB -55 -50 dB VDD=VDDA=2.5V to 5.5V, mV CMRR Common mode rejection ratio │IIH│ High-level input current VDD=VDDA=5.5V, VI=5.8V (SDNB) 40 µA │IIL│ Low-level input current VDD=VDDA=5.5V, VI=-0.3V (SDNB) 1 µA IQ Quiescent current VDD=VDDA=5V, no load 2 3 mA 0.2 0.5 µA VIC=1Vpp, RL=8Ω V(SDNB)=0.8V, IQ (SD) Shutdown current rDS(on) f(sw) Static drain-source on-state resistance VDD=VDDA=5.5V Switching frequency VDD=VDDA=2.5V to 5.5V *Av BTL Gain VDD=VDDA=2.5V to 5.5V, RL=8Ω RSDNB Resistance from shutdown to GND V(SDNB)=5V ZI Input impedance IN+, IN- VDD=VDDA=2.5V to 5.5V 790 mΩ 200 250 300 kHz 17 21 25 V/V 200 12 15 kΩ 18 kΩ *The gain of the amplifier is determined by, for VDD=VDDA =2.5V to 5.5V Gain = 320kohms Ri + 15kohms Copyright ©2005, Tai-1 Microelectronics Corp. where Ri is the external serial resistance at the input pin. 3 tai'mec Preliminary www.taimec.com.tw / www.class-d.com.tw TMPA2155DM Rev.1.0 December 24, 2007 OPERATING CHARACTERISTICS TA=25。C, RL=8Ω speaker (unless otherwise noted) PARAMETER TEST CONDITIONS RL=8Ω PO Output power / Ch THD+N TYP MAX UNIT 1.5 W 2.3 W RL=3Ω 2.7 W VDD=AVDD=5V, PO=0.85W, RL=8Ω, f=1kHz 0.55 VDD=AVDD=5V, PO=1.3W, RL=4Ω, f=1kHz 0.55 VDD=AVDD=5V, PO=1.5W, RL=3Ω, f=1kHz 0.64 RL=4Ω Total harmonic distortion plus noise MIN VDD=AVDD=5V. THD+N=10%,f=1kHz. % SNR Signal-to-noise ratio VDD=AVDD=5V, PO=1W, RL=8Ω 85 dB Crosstalk Crosstalk between outputs VDD=AVDD=5V, PO=1W RL=8Ω -60 dB TERMINAL FUNCTIONS TERMINAL I/O NAME DESCRIPTION PIN NO GND 2 I Digital ground IN- 4 I Negative differential input IN+ 3 I Positive differential input SDNB 5 I Shutdown terminal (active low logic) VDD 7 I Digital Power supply VDDA 6 I Analog Power supply V O+ 1 O Positive BTL output V O- 8 O Negative BTL output TYPICAL CHARACTERISTICS Note 1. Input coupling 1µF capacitors are used for all measurements. 2. Differential inputs are applied and BTL outputs are measured. 3. Balanced LC filter is used for THD+N measurement and power efficiency measurement. 4. Characteristic frequency of the LC filter is set 41KHz unless otherwise specified. Copyright ©2005, Tai-1 Microelectronics Corp. 4 tai'mec Preliminary www.taimec.com.tw / www.class-d.com.tw TMPA2155DM Rev.1.0 December 24, 2007 APPLICATION INFORMATION Copyright ©2005, Tai-1 Microelectronics Corp. 5 tai'mec Preliminary www.taimec.com.tw Copyright ©2005, Tai-1 Microelectronics Corp. / www.class-d.com.tw TMPA2155DM Rev.1.0 December 24, 2007 6 tai'mec Preliminary www.taimec.com.tw / www.class-d.com.tw TMPA2155DM Rev.1.0 December 24, 2007 Input Resistors and Gain The gain of the amplifier is determined by, for VDD=VDDA =2.5V to 5.5V Gain = 320kohms where Ri is the source impedance of the input signal. Ri + 15kohms Note：Please refer to document 010 APP for more application examples. Copyright ©2005, Tai-1 Microelectronics Corp. 7 tai'mec Preliminary www.taimec.com.tw / www.class-d.com.tw TMPA2155DM Rev.1.0 December 24, 2007 DETAILED DESCRIPTION Efficiency The output transistors of a class D amplifier act as switches. The power loss is mainly due to the turn on resistance of the output transistors when driving current to the load. As the turn on resistance is so small that the power loss is small and the power efficiency is high. With 8 ohm load the power efficiency can be better than 85%. Shutdown The shutdown mode reduces power consumption. A LOW at shutdown pin forces the device in shutdown mode and a HIGH forces the device in normal operating mode. Shutdown mode is useful for power saving when not in use. This function is useful when other devices like earphone amplifier on the same PCB are used but class D amplifier is not necessary. Internal circuit for shutdown is shown below. Pop-less The shutdown pin is designed to give pop-less start up. The RC delay provided by external R(=100k ohms) and external C(=1uF) introduces enough delay for the internal circuitry to be stable before the signal is fed to the speaker. This delay is good for shutdown ON-OFF and power UP-DOWN operations. Voltage gain The voltage gain is defined in the table on page 3. For lower voltage gain one can add external input resistors to input pins. If external resistors are used they should be well matched. Well matched input resistors are also required even for single ended input configuration for low noise. Copyright ©2005, Tai-1 Microelectronics Corp. 8 tai'mec Preliminary www.taimec.com.tw / www.class-d.com.tw TMPA2155DM Rev.1.0 December 24, 2007 Automatic output Power Control (APC) The voltage gain is self adjusted in the chip over voltage range. This means that, regardless supply voltage change, the output power keeps about the same for a given input level from VDD=5.5v to 2.5v. It allows the best use of the battery. Differential input VS single ended input Differential input offers better noise immunity over single ended input. A differential input amplifier suppresses common noise and amplifies the difference voltage at the inputs. For single ended applications just tie the negative input end of the balanced input structure to ground. If external input resistors are used, the negative input has to be grounded with a series resistor of the same value as the positive input to reduce common noise. Output filter Ferrite bead filter can be used for EMI purpose. The ferrite filter reduces EMI around 1 MHz and higher（FCC and CE only test radiated emissions greater than 30 MHz）. When selecting a ferrite bead, choose one with high impedance at high frequencies, but low impedance at low frequencies. Use an LC output filter if there are low frequency（＜1 MHz）EMI sensitive circuits and/or there are long wires from the amplifier to the speaker. EMI is also affected by PCB layout and the placement of the surrounding components. Copyright ©2005, Tai-1 Microelectronics Corp. 9 tai'mec TMPA2155DM Preliminary www.taimec.com.tw / www.class-d.com.tw Rev.1.0 December 24, 2007 The suggested LC values for different speaker impendence are showed in following figures for reference. Typical LC Output Filter (1) 33μH Vo+ 0.47µ F 0.1µ F 33μH Vo0.1µ F Typical LC Output Filter (2) Copyright ©2005, Tai-1 Microelectronics Corp. 10 TMPA2155DM Preliminary www.taimec.com.tw / www.class-d.com.tw Physical Dimensions Rev.1.0 December 24, 2007 ( IN MILLIMETERS) 5 E 8 1 H tai'mec 4 0.05TYP. 0.016TYP. 0.063 0.120 SYMBOLS MIN. MAX. A 0.053 0.069 A1 0.004 0.010 D 0.189 0.196 E 0.150 0.157 H 0.228 0.244 SOP8 Copyright ©2005, Tai-1 Microelectronics Corp. 11 tai'mec TMPA2155DM Preliminary www.taimec.com.tw / www.class-d.com.tw Physical Dimensions Rev.1.0 ( IN MILLIMETERS) SYMBOLS MIN. NDM. MAX. A - - 1.20 A1 0.05 - 0.15 A2 0.96 1.01 1.06 D 2.90 3.00 3.10 E E1 December 24, 2007 6.40 BSC 4.30 4.40 4.50 TSSOP8 Copyright ©2005, Tai-1 Microelectronics Corp. 12 tai'mec Preliminary www.taimec.com.tw / www.class-d.com.tw TMPA2155DM Rev.1.0 December 24, 2007 IMPORTANT NOTICE Tai-1 Microelectronics Corp. reserves the right to make changes to its products and services and to discontinue any product or service without notice. Customers should obtain the latest relevant information for reference. Testing and quality control techniques are used to screen the parameters. Testing of all parameters of each product is not necessarily performed. Tai-1 Microelectronics Corp. assumes no liability for applications assistance or customer product design. To minimize the risks associated with customer products and applications, customers should provide adequate design and operating safeguards. Reproduction of information in data sheets or related documentation is permissible only if reproduction is without alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Tai-1 Microelectronics Corp. is not responsible or liable for such altered documentation. Resale of Tai-1 Microelectronics Corp. products or services with statements different from the parameters stated by Tai-1 Microelectronics Corp. for that product or service voids all express and any implied warranties. Tai-1 Microelectronics Corp. is not responsible or liable for any such statements. Copyright ©2005,Tai-1 Microelectronics Corp. Copyright ©2005, Tai-1 Microelectronics Corp. 13