Leshan Radio Co ., Ltd LR6311 3 Watt Mono Filter-Free Class-D Audio Power Amplifier Features Efficiency With an 8-Ω Speaker: 88% at 400 mW 80% at 100 mW 2.6mA Quiescent Current 0.4µA Shutdown Current Optimized PWM Output Stage Eliminates LC Output Filter Internally Generated 250-kHz Switching Frequency Eliminates Capacitor and Resistor Improved PSRR (−75 dB) and Wide Supply Voltage (2.5 V to 5.5 V) Eliminates Need for a Voltage Regulator Fully Differential Design Reduces RF Rectification and Eliminates Bypass Capacitor Improved CMRR Eliminates Two Input Coupling Capacitors Available in space-saving package: 9-bump WLCSP General Description ss-D audio power amplifier in The LR6311 is a 3-W high efficiency filter-free cla a wafer chip scale package (WCSP) that requires only three external components. Features like 88% efficiency, −75dB PSRR, and improved RF-rectification immunity make the LR6311 ideal for cellular handsets. In cellular handsets, the earpiece, speaker phone, and melody ringer can each be driven by the LR6311. Applications Mobile phone、PDA MP3/4、PMP Portable electronic devices 1/13 Leshan Radio Co ., Ltd 1 Pin Diagrams 2 3 A IN+ GND VO- B VDD PVDD PGND C IN- SDB VO+ top view Pin Description Pin # A1 A2 A3 B1 B2 B3 C1 C2 C3 Name IN+ GND VOVDD PVDD PGND INSDB VO+ Description Positive differential input Power Ground Negative BTL output Power Supply Power Supply Power Ground Negative differential input Shutdown terminal (low active) Positive BTL output Function Block Diagram Av1 = 150k/Ri (B1) VDD 150k (B2) PVDD (C1) IN- (A3) Vo- PWM Modulator and Power Driver Amp1 (A1) IN+ (C3) Vo+ Av2 = 2 V/V (B3) PGND 150k (C2) SDB ShutDown Control 300k Start up & Protection Bias & Reference OSC & RAMP (A2) GND OC Detect 150k Notes: Total Voltage Gain = Av1 × Av 2 = 2 × RI Figure 1. Function Block Diagram 2/13 Leshan Radio Co ., Ltd Application Circuit VDD Ri Vi- + Differential Input Vi+ + ) p o Lo TL B &d e Ms Wo Pl C ( To Battery Cs Vo+ Vo- Ri GND Bias & ShutDown SDB OSC & RAMP Figure 2. LR6311 Application Schematic With Differential Input VDD Ci Ri Vi- + Differential Input Vi+ Ci + ) p o Lo T BL &d s Me W l Po C ( To Battery Cs Vo+ Vo- Ri GND Bias & ShutDown SDB OSC & RAMP Figure 3. LR6311 Application Schematic With Differential Input and Input Capacitors VDD Ci Single-ended Input Ri Vi- + Vi+ Ci + ) p o Lo T BL &d s Me W l Po C ( To Battery Cs Vo+ Vo- Ri GND SDB Bias & ShutDown OSC & RAMP Figure 4. LR6311 Application Schematic With Single-Ended Input 3/13 Leshan Radio Co ., Ltd Electrical Characteristics The following specifications apply for the circuit shown in Figure 5. TA = 25℃, unless otherwise specified. Symb Spec Parameter Conditions Units ol Min. Typ. Max. ISD Shutdown Current IQ Quiescent Current VOS Output Offset Voltage PSRR Power Supply Rejection Ratio VIN=0V, VSDB=0V, No Load 0.4 VDD = 2.5V, VIN = 0V, No Load 2.0 VDD = 3.6V, VIN = 0V, No Load 2.6 VDD = 5.5V, VIN = 0V, No Load VIN = 0V, AV = 2V/V, VDD = 2.5V to 5.5V 3.0 8 2 25 -75 dB -68 dB FSW Modulation frequency VDD = 2.5V to 5.5V VDD = 2.5V to 5.5V, VIC = VDD/2 to 0.5V, VIC = VDD/2 to VDD - 0.8V VDD = 2.5V to 5.5V AV Voltage gain VDD = 2.5V to 5.5V CMRR Common Mode Rejection Ratio RSDB ZI TWU rDS(on) Resistance from SDB to GND Input impedance Wake-up time from shutdown VDD = 3.6V VDD = 2.5V Drain-Source resistance (on-state) VDD = 3.6V VDD = 5.5V 200 285k RI 142 2 uA mA 250 300k RI 300 150 1 700 500 400 300 mV kHz 315k RI V/V 158 kΩ kΩ mS mΩ Operating Characteristics VDD = 5V, RI = 150kΩ, TA = 25℃, unless otherwise specified. Symb Spec Parameter Conditions Units ol Min. Typ. Max. PO THD+N SNR Output Power THD+N=10%, f=1KHz, RL = 4Ω THD+N=1%, f=1KHz, RL = 4Ω THD+N=10%, f=1KHz, RL = 8Ω THD+N=1%, f=1KHz, RL = 8Ω Total Harmonic Po=1.0Wrms, f=1kHz, RL = 8Ω Distortion + Noise Signal-to-Noise ratio VDD=5V, Po=1.0Wrms, RL = 8Ω 3.0 2.4 1.7 1.4 W 0.19 % 97 dB VDD = 3.6V, RI = 150kΩ, TA = 25℃, unless otherwise specified. Spec Symb Units Parameter Conditions ol Min. Typ. Max. PO THD+N Output Power Total Harmonic Distortion + Noise Supply ripple rejection ratio THD+N=10%, f=1KHz, RL = 4Ω THD+N=1%, f=1KHz, RL = 4Ω THD+N=10%, f=1KHz, RL = 8Ω THD+N=1%, f=1KHz, RL = 8Ω 1.5 1.2 0.9 0.7 W Po=0.5Wrms, f=1kHz, RL = 8Ω 0.19 % -68 dB 48 36 uVRMS -70 dB VDD = 3.6V, input ac-grounded with CI = 2uF f=217Hz, V(Ripple)=200mVPP V = 3.6V, input ac-grounded No weighting Vn Output voltage noise DD with CI = 2uF, f=20~20kHz A weighting Common Mode CMRR VDD = 3.6V, VIC = 1 VPP, f=217Hz Rejection Ratio KSVR VDD = 2.5V, RI = 150kΩ, TA = 25℃, unless otherwise specified. Parameter Conditions Spec Units 4/13 Leshan Radio Co ., Ltd Symb ol THD+N Parameter Conditions Total Harmonic Distortion + Noise Spec Units Min. Typ. Max. THD+N=10%, f=1KHz, RL = 4Ω THD+N=1%, f=1KHz, RL = 4Ω THD+N=10%, f=1KHz, RL = 8Ω THD+N=1%, f=1KHz, RL = 8Ω 0.7 0.55 0.4 0.3 Po=0.2Wrms, f=1kHz, RL = 8Ω 0.19 % Test Circuit Ci Signal input from measurement 2uF Ri 150K IN+ VO+ LR6311 Vin Ci 2uF Ri 150K Shutdown signal IN- 30KHz LPF RL Output to measurement VO VO- SDB VDD GND CS 1uF Power + Supply - Figure 5. LR6311 test set up circuit VO+ 100 47nF VO- VO 100 47nF 30kHz LPF Figure 6. 30-kHz LPF for LR6311 test Notes: 1>. CS should be placed as close as possible to VDD/GND pad of the device 2>. Ci should be shorted for any Common-Mode input voltage measurement 5/13 Leshan Radio Co ., Ltd 3>. A 33uH inductor should be used in series with RL for efficiency measurement 4>. The 30 kHz LPF (shown in figure 5) is required even if the analyzer has an internal LPF Component Recommended Due to the weak noise immunity of the single-ended input application, the differential input application should be used whenever possible. The typical component values are listed in the table: RI CI CS 150 k 3.3 nF 1 uF (1) CI should have a tolerance of ±10% or better to reduce impedance mismatch. (2) Use 1% tolerance resistors or better to keep the performance optimized, and place the RI close to the device to limit noise injection on the highimpedance nodes. Input Resistors (RI) & Capacitors (CI) The input resistors (RI) set the total voltage gain of the amplifier according to Eq1 Gain = 2 × 150kΩ RI V V Eq1 The input resistor matching directly affects the CMRR, PSRR, and the second harmonic distortion cancellation. If a differential signal source is used, and the signal is biased from 0.5V ~ VDD0.8V (shown in Figure2), the input capacitor (CI) is not required. If the input signal is not biased within the recommended common-mode input range in differential input application (shown in Figure3), or in a single-ended input application (shown in Figure4), the input coupling capacitors are required. If the input coupling capacitors are used, the RI and CI form a high-pass filter (HPF). The corner frequency (fC) of the HPF can be calculated by Eq2 fC = 1 2π ⋅ RI ⋅ C I (Hz ) Eq 2 Decoupling Capacitor (CS) A good low equivalent-series-resistance (ESR) ceramic capacitor (CS), used as power supply decoupling capacitor (CS), is required for high power supply rejection (PSRR), high efficiency and low total harmonic distortion (THD). Typically CS is 1µF, placed as close as possible to the device VDD pin. 6/13 Leshan Radio Co ., Ltd Typical Performance Characteristics Audio Precision 20 10 5 2 % 1 0.5 0.2 0.1 6m 10m 20m 50m 100m 200m 500m 1 2 3 W Sweep Trace Color Line Style Thick Data 1 2 3 4 1 1 1 1 Cyan Green Yellow Red Solid Solid Solid Solid 1 1 1 1 Analyzer.THD+N Analyzer.THD+N Analyzer.THD+N Analyzer.THD+N Ratio Ratio Ratio Ratio B B B B Axis Com m ent Left Left Left Left 2.5v 3v 3.6v 5v Figure7 THDN vs PO (RL=4ohm, f=1kHz, Gain=2) Audio Precision 20 10 5 % 2 1 0.5 0.2 0.1 5m 10m 20m 50m 100m 200m 500m 1 W Sweep Trace Color Line Style Thick Data Axis Comment 1 2 3 4 1 1 1 1 Magenta Red Yellow Green Solid Solid Solid Solid 1 1 1 1 .Analyzer.THD+N Ratio B .Analyzer.THD+N Ratio B .Analyzer.THD+N Ratio B .Analyzer.THD+N Ratio B Left Left Left Left 2.5V 3V 3.6V 5V Figure8 THDN vs PO (RL=8ohm, f=1kHz, Gain=2) 7/13 Leshan Radio Co ., Ltd Audio Precision 100 10 1 % 0.1 0.01 0.001 0.0001 20 50 100 200 500 1k 2k 5k 10k 20k Hz Sweep Trace Color 1 2 3 1 1 1 Line Style Thick Data Green Solid Cyan Solid Yellow Solid 1 1 1 Axis Comment Analyzer.THD+N Ratio B Left Analyzer.THD+N Ratio B Left Analyzer.THD+N Ratio B Left Po=25mW Po=250mW Po=1w Figure9 THDN vs Frequency (VDD=5V RL=8ohm Gain=2 CI=2uF) Audio Precision 10 1 % 0.1 0.01 20 50 100 200 500 1k 2k 5k 10k 20k Hz Sweep Trace Color Line Style Thick Data Axis 1 2 3 1 1 1 Green Cyan Yellow Solid Solid Solid 1 1 1 Analyzer.THD+N Ratio B Analyzer.THD+N Ratio B Analyzer.THD+N Ratio B Left Left Left Comment Figure10 THDN vs Frequency (VDD=3.6V RL=8ohm Gain=2 CI=2uF) 8/13 Leshan Radio Co ., Ltd Audio Precision 10 1 % 0.1 0.01 20 50 100 200 500 1k 2k 5k 10k 20k Hz Sweep Trace Color 1 2 3 1 1 1 Line Style Thick Data Green Solid Cyan Solid Yellow Solid 1 1 1 Axis Analyzer.THD+N Ratio B Left Analyzer.THD+N Ratio B Left Analyzer.THD+N Ratio B Left Comment Po=15mW Po=75mW po=200mW Figure11 THDN vs Frequency (VDD=2.5V RL=8ohm Gain=2 CI=2uF) Audio Precision -40 -60 d B -80 -100 -120 20 50 100 200 500 1k 2k 5k 10k 20k Hz Sweep Trace Color 1 2 3 1 1 1 Line Style Thick Data Blue Solid Green Solid Red Solid 1 1 1 Axis Analyzer.Crosstalk B Left Analyzer.Crosstalk B Left Analyzer.Crosstalk B Left Comment 5V 3.6V 2.5V Figure12 PSRR vs Frequency (RL=4ohm, Input ac-grounded) 9/13 Leshan Radio Co ., Ltd Audio Precision -40 -60 d B -80 -100 -120 20 50 100 200 500 1k 2k 5k 10k 20k 10k 20k Hz Sweep Trace Color 1 2 3 1 1 1 Line Style Thick Data Cyan Solid Green Solid Yellow Solid 1 1 1 Axis Comment Analyzer.Crosstalk B Left 5v Analyzer.Crosstalk B Left 3.6v Analyzer.Crosstalk B Left 2.5v Figure13 PSRR vs Frequency (RL=8ohm, Input ac-grounded) Audio Precision -40 -60 d B -80 -100 -120 20 50 100 200 500 1k 2k 5k Hz Sweep Trace Color 1 2 3 1 1 1 Line Style Thick Data Blue Solid Green Solid Red Solid 1 1 1 Axis Analyzer.Crosstalk B Left Analyzer.Crosstalk B Left Analyzer.Crosstalk B Left Comment 5V 3.6V 2.5V Figure14 PSRR vs Frequency (RL=8ohm, Input floating) 10/13 Leshan Radio Co ., Ltd Efficiency vs Po 1 0.9 Efficiency % 0.8 0.7 0.6 0.5 0.4 0.3 0.2 Vdd=5V Vdd=2.5 0.1 0 0 0.02 0.05 0.1 0.15 0.2 0.25 0.4 0.5 0.6 0.8 1 Po 1.2 Figure15 GSM Power Supply Rejection vs Time (RL=8Ω Ω+33uH) Supply Current vs Po 0.3 Vdd=5V Vdd=2.5V 0.25 IDD (A) 0.2 0.15 0.1 0.05 0 0 0.02 0.05 0.1 0.15 0.2 0.25 0.4 0.5 0.6 0.8 1 1.2 Po (W) Figure16 Supply Current vs Output Power (RL=8Ω Ω +33uH) 11/13 Leshan Radio Co ., Ltd Audio Precision 200m 40m 100m 20m 0 V 0 V -100m -20m -200m -40m 0 5m 10m 15m 20m 25m 30m s Sweep Trace Color Line Style Thick Data Axis 1 1 1 2 Cyan Green Solid Solid 1 1 Left Right FFT.ChA Amplitude FFT.ChB Amplitude Comment Figure17 GSM Power Supply Rejection vs Time Audio Precision -20 +100 +75 -40 +50 V D D ( d B V ) -60 +25 V o +0 -80 ( -25 -100 -50 -75 -120 d B V ) -100 -140 -125 0 200 400 600 800 1k 1.2k 1.4k 1.6k 1.8k 2k Hz Sweep Trace Color 1 1 1 2 Line Style Thick Data Cyan Solid Green Solid 1 1 Axis Comment FFT.ChAAmplitude Left FFT.ChBAmplitude Right Figure18 GSM Power Supply Rejection vs Frequency 12/13 Leshan Radio Co ., Ltd Package Dimensions 9 Bump WLCSP Dimensions (mm) REF A1 A2 A3 D D1 E E1 b CCC MIN 0.215 0.355 0.020 1.485 1.485 0.300 TYP MAX 0.235 0.255 0.380 0.405 0.035 0.050 1.500 1.515 0.500 1.500 1.515 0.500 0.320 0.340 0.080 13/13