LX1708ILQ

LX1708 TM ® 15+15W Stereo Filterless Class-D Amplifier P RODUCTION D ATA S HEET DESCRIPTION KEY FEATURES Filter Free Operation 15W +15W Output Power @ 4Ω load: THD+N < 1% High Efficiency > 85% Full Audio Bandwidth: 20Hz to 20KHz Low Distortion < 0.15% @ 30% Max Power, 1KHz High Signal-to-Noise Ratio: 90dB Wide Supply Voltage Range 5.0V ~ 15V Low Quiescent Current < 30mA Turn ON/OFF POP Free Standby / Mute Feature Built-in Under Voltage Lockout Thermal Protection Short Circuit Protection APPLICATIONS The LX1708 is part of a new generation of fully integrated stereo class-D amplifiers from Microsemi. This CMOS audio amplifier is optimized for highly efficient operation and minimum system cost. The stereo BTL (Bridge-tied-load) configuration uses 3-level PWM modulation. This allows eliminating the LC filter to reduce the system cost and simplify the system design. The LX1708 outputs 15W into each of two channels with better than 85% efficiency. The part features on–board H-bridge output stages with low RDSON. External bootstrap capacitors are all that is required to provide the gate drive to the all-NFET output stage since onboard bootstrap diodes are provided. The LX1708 also features Mute and Standby modes, over-current protection, POP-free turn-on and turn-off, undervoltage lockout, over-voltage protection, and over-temperature protection. The LX1708 is offered in a small footprint, low profile surface mountable 32-pin Micro Lead Quad Package (MLPQ) in 7mm x 7 mm. W WW . Microsemi . C OM LCD TV Car Navigation Computer: Portable Sound System IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com PRODUCT HIGHLIGHT STBY 5V AVSS1 PVSS1N OUT1N BOOT1N PVDD1 AVSS2 PVSS2N OUT2N BOOT2N V5V STATUS N.C. ROSC TMON PVDD PVDD1 BOOT1P OUT1P LX1708 TCTRL MUTE VREF IN1P N.C. STBY PVDD2 PVDD2 BOOT2P OUT2P PVDD PVSS1P IN1N PVSS2P IN2P IN2N IN2N IN1N IN1P IN2P MUTE LX1708 LX1708 PACKAGE ORDER INFO TA (°C) -40 to 85 LQ Plastic MLPQ 32-Pin 7mmx7mm LX1708ILQ RoHS Compliant / Pb-free Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX1708ILQ-TR) Copyright © 2004 Rev.1.2, 2007-01-05 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 1 LX1708 TM ® 15+15W Stereo Filterless Class-D Amplifier P RODUCTION D ATA S HEET ABSOLUTE MAXIMUM RATINGS Analog Supply Voltage (PVDD) ................................................................. -0.3V to 16.5V Supply Voltage (V5V) ......................................................................................... -0.3 to 6V STBY to VSS......................................................................................-0.3V to V5V + 0.3V IN1P/M, IN2P/M .................................................................................-0.3V to V5V +0.3V Maximum Operating Junction Temperature .............................................................. 150°C Storage Temperature Range.........................................................................-65°C to 150°C Package Peak Temp. for Solder Reflow (40 seconds maximum exposure) ... 260°C (+0 -5) 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. PACKAGE PIN OUT W WW . Microsemi . C OM BOOT1N BOOT1P 30 PVSS1N PVSS1P 32 OUT1N OUT1P 31 PVDD1 29 PVDD1 28 27 26 25 24 23 22 21 20 19 18 17 STBY IN1P IN1N N.C. N.C. IN2N IN2P MUTE 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 TCTRL TMON AVSS2 ROSC VREF AVSS1 V5V STATUS PVSS2P OUT2P BOOT2P PVDD2 PVDD2 BOOT2N OUT2N PVSS2N THERMAL DATA LQ PACKAGE (Top View) LQ Plastic MLPQ 32-Pin 7mm x 7mm THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA Pb-free 100% Matte Tin Lead Finish 15.5°C/W Junction Temperature Calculation: TJ = TA + (PD x θJA). The θJA numbers are guidelines for the thermal performance of the device/pc-board system. All of the above assume no ambient airflow. P D PACKAGE DATA Copyright © 2004 Rev.1.2, 2007-01-05 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 2 LX1708 TM ® 15+15W Stereo Filterless Class-D Amplifier P RODUCTION D ATA S HEET FUNCTIONAL PIN DESCRIPTION Name PVSS1P PVSS1N PVSS2P PVSS2N PVDD1 PVDD2 V5V AVSS1 AVSS2 IN1N IN1P IN2N IN2P OUT1N OUT1P OUT2N OUT2P BOOT1N BOOT1P BOOT2N BOOT2P VREF Power Ground # Of Pins 4 Description Power Ground for the two H-bridge output drivers. Power Supply for the two H-bridge output drivers. Operating voltage is from 4.5 up to 15V. Current draw will be up to 3.2A at 2X15W into 8ohms or up to 4.5A at 2X15W into 4 ohms. These are peak currents when the part is run at maximum rated power on both channels. Analog Power Supply for the analog signal processing section. Operating voltage is from 4.5 up to 5.5V. Analog Ground for the analog signal processing section. Should be at the same voltage as PVSS. Also used to bias the substrate. Differential analog audio inputs for each channel. The common mode voltage will be set by the LX1708 to around 2.25V. Differential high power audio outputs for each channel. Each output will swing between PVDD and PVSS. These outputs are driven by an on-chip H-bridge output driver which uses low Rdson NFETs. Bootstrap voltage pins which provide the high voltage needed to drive the upper NFET. A bootstrap capacitor should be placed between the respective output and these pins. 2.25V reference voltage which serves as a local “GND” reference. An external compensation capacitor of at least 1uF should be connected between this pin and AVSS. Logic level control which mutes the audio signal when high. This will be a four level pin to allow testing of the low gain mode as follows: From 0 to ¼ of V5V, the gain will be normal. From ¼ of V5V to ½ of V5V, the gain will be low Above ½ of V5V, the gain will be muted. Logic level control which places the chip into sleep mode when high. The logic threshold will be at ½ of V5V. Digital monitoring pin which is used to flag internal fault states. This pin will be synchronized with the internal clock to prevent glitches. See the STATUS flag table for a summary of which conditions will force this pin to go high. Frequency control pin. A resistor between this pin and GND will set the oscillation frequency for the Class-D modulator. Test purpose only, Connect to AVSS1 Test purpose only, left open. No Connect W WW . Microsemi . C OM Power Supply Power Supply Analog Ground Analog Input 4 1 2 4 Digital Output 4 Digital Output Analog Output CMOS Input CMOS Input CMOS Output Analog Input CMOS Input Analog I/O 4 1 MUTE 1 STBY STATUS ROSC TCTRL TMON N.C. 1 1 1 1 1 2 P D PACKAGE DATA The STATUS pin will go under any of the following conditions: STBY is high. This indicates that the chip is in “stand-by” mode. V5V is below the UVLO threshold. The outputs will be forced into the low state. PVDD is below the PVDD UVLO threshold. The outputs will be forced into the low state. PVDD is above the over-voltage threshold which is about 17.8V. The outputs will be forced into the low state. The die temperature is above about 140°C. This indicates that the part has gone in to gain foldback. A short circuit at the output has caused the output devices to shut off due to excessive temperature. Copyright © 2004 Rev.1.2, 2007-01-05 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 3 LX1708 TM ® 15+15W Stereo Filterless Class-D Amplifier P RODUCTION D ATA S HEET ELECTRICAL CHARACTERISTICS Unless otherwise specified, the following specifications apply over the operating ambient temperature -40°C < TA < 85°C except where otherwise noted and the following test conditions: PVDD = 12V, PVSS = AVSS = 0V, V5V = 5V, ROSC = 25KΩ Parameter OSCILLATOR Oscillator Frequency Temperature Stability POWER SUPPLY Supply Voltage UVLO UVLO Hysteresis +5V Supply UVLO UVLO Hysteresis Stand-By Current Operating Current Stand-By Current Operating Current Power Supply Rejection Ratio 1 Reference Voltage GAIN Stage Gain @ 0dB Volume Mute Gain @ minimum volume OFFSET Output DC Offset INPUT STAGE Input Resistance Common Mode Voltage OUTPUT STAGE MOSFET On Resistance THERMAL Thermal Shut Off Junction Temperature Hystersis MUTE / STBY / MASTER MUTE Threshold STBY Threshold STBY To Output Enable Power On Reset Delay Note 1: Not ATE Tested After Power on Reset Pulse, Not Quick Mode 0.20 Mute Mode RDSON IDS = 200mA 280 150 25 mΩ °C °C V V 3.8 Clocks mS PVDD PVDD PVDD V5V V5V V5V IQQ IQQ IQQ5V5 IQQ5V5 PSRR VREF G GMUTE VOFF RIN VCM FOSC Varies with ROSC resistor value, value shown is for default conditions. R = 25K TA = 0°C to 70°C TA = -40°C to 125°C 5.0 Start-up Voltage 4.5 Start-up Voltage For PVDD, STBY high For PVDD, STBY low, Mute high For 5V5, STBY high For 5V5, STBY low, Mute high For PVDD C bypass = 1µF f = 1KHz Mute active, Input shorted Measured Differentially. OUT1- to OUT1+ OUT2- to OUT2+ 4.25 250 10 10 10 7 55 2.25 20 0.01 100 22 2.25 300 5 8 12 4.50 500 15 4.90 5.5 4.50 50 30 15 KHz % % V V mV V V mV µA mA µA mA dB V V/V V/V mV KΩ V Symbol Test Conditions LX1708 Typ Units W WW . Microsemi . C OM Min Max V5V 2 V5V 2 16384 0.30 E ELECTRICALS Note: Functionality over the -40°C to +85°C operating range is assured by design characterization and correlation. Caution: Power Up/Down Sequencing Power-on: Apply V5V w/STBY=V5V. Then apply PVDD. Then bring STBY low. Power-off: Bring STBY high such that STBY=V5V. Then shut off PVDD. Then shut off V5V. Copyright © 2004 Rev.1.2, 2007-01-05 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 4 LX1708 TM ® 15+15W Stereo Filterless Class-D Amplifier P RODUCTION D ATA S HEET SYSTEM MODULE CHARACTERISTICS Unless otherwise specified, the following specifications apply over the operating ambient temperature -40°C < TA < 85°C except where otherwise noted and the following test conditions: PVDD = 12V, PVSS = AVSS = 0V, V5V = 5V, ROSC = 25KΩ, RL = 4Ω. Parameter AUDIO CHARACTERISTICS Symbol Test Conditions LX1708 Typ Units W WW . Microsemi . C OM Min Max Output Power Stereo PO Total Harmonic Distortion Stereo Power Efficiency Channel Crosstalk Audio Bandwidth Stage Gain Stereo Mute Output Signal to Noise Ratio Output Noise Floor Common Mode Rejection Ratio Output Short Circuit Protection High Low THD+N VXTALK BW VMUTE SNR VN CMRR TSENSE THD+N < 1% THD+N 0.15mm) must be met to prevent solder bridging. If this clearance cannot be met, then D2th should be reduced in area. The formula would be: D2TH > D2 only if D2TH < Gmin – (2 x Cpl). C7, C10, C11, C12, C13, and C16 are bypassing capacitors for input supplies and internal reference voltage (2.5V), nominal value is 1µF. These capacitors should be placed as close to the IC as possible also, to guarantee low ripples and noise. Copyright © 2004 Rev.1.2, 2007-01-05 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 10 LX1708 TM ® 15+15W Stereo Filterless Class-D Amplifier P RODUCTION D ATA S HEET APPLICATION NOTE/PCB DESIGN GUIDLINE (CONTINUED) THERMAL PAD VIA DESIGN W WW . Microsemi . C OM There are two types of on-board thermal PAD designs: one is using thermal vias to sink the heat to the other layer with metal traces. Based on the Jedec Specification (JESD 51-5) the thermal vias should be designed like Figure 5. Another one is the no via thermal PAD which is using the same copper PAD as heat sink, this type of thermal PAD is good for a two layer board, since the bottom side is filled with all other kinds of trace also, it’s hard to use the whole plane for the heat sink. But you still can use vias to sink the heat to the bottom layer by the metal traces, then layout a NMSD on which a metal heat sink is put to sink the heat to the air. The LX1708 is supplied in an MLPQ – 7mm x 7mm, 32 pin package. θJA = 15.5°C/W for the package by itself in still air. When running at a continuous 20W output power, the on-chip power dissipation will be 3.5W assuming 85% efficiency. With no reduction in the thermal resistance, the die temperature will rise 103 about ambient. θJC is about 4° C/W. if the exposed pad is properly connected to a heat sink, then the temperature rise will be reduced to around 16°C under these conditions. So the via type thermal PAD is suggested. ~0.85mm ~0.025mm Zmin ~7.45mm ~0.355mm 0.305mm D2th ~5.15mm 1.2mm Gmin ~6.00mm Micro Lead Quad Land Pattern for Four Package Land Pattern Layer Board with Vias Figure 5 – Comparison of land pattern theory Ø 0.3mm 5.00mm Figure 6 – Recommended Land Pad with Vias for LQ32 (7mm2) Zmin=D + aaa+ 2(0.2) (where pkg body tolerance aaa=0.15) (where 0.2 is outer pad extension) Gmin=D-2(Lmax)-2(0.05) (where 0.05 is inner pad extension) (Lmax=0.05 for this example) D2th max = Gmin-2(CpL) (where CpL=0.2) Copyright © 2004 Rev.1.2, 2007-01-05 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 11 LX1708 TM ® 15+15W Stereo Filterless Class-D Amplifier P RODUCTION D ATA S HEET PRINTED CIRCUIT BOARD FOR THE LXE1708 W WW . Microsemi . C OM Figure 7 – Inner Layer 1 Figure 8 – Bottom Layer Figure 10 – Inner Layer 2 Figure 9 – Top Layer Figure 11 – Top Component Layer Copyright © 2004 Rev.1.2, 2007-01-05 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 12 LX1708 TM ® 15+15W Stereo Filterless Class-D Amplifier P RODUCTION D ATA S HEET LX1708 EVAL KIT BILL OF MATERIALS W WW . Microsemi . C OM MISCELLANEOUS COMPONENTS Line Item 1 2 3 4 5 6 7 8 9 10 Part Description Microsemi IC Controller LX1708 Class-D Audio Amplifier Diode, Schottky Jack, PCB Mount, RCA Header, 2 Position Vertical Header, 3 Position, 2 Row Vertical 0.1” Centers Switch, SPDT, PCB Mount Subminiature Terminal Block, 2 Position Terminal, Compact, Test Point Terminal, Subminiature, PCB, LX1708 Evaluation Board Manufacturer & Part # MICROSEMI MICROSEMI KEYSTONE 3M 3M C&K BLOCKMASTER KEYSTONE KEYSTONE MICROSEMI CAPACITORS GT11MSAKE 301-021-1000 5016 5015 SGE2874-X1 LX1708ILQ UPS5817 901 929450-01-02-1 Case MLPQ-32 Powermite Reference Designators U1 CR1, CR2, CR7, CR8 J1, J2 JP1 – JP7 JP3 SW1 TB1, TB2, TB3, TB4 Qty 1 N/U 2 6 1 1 4 2 9 SMT SMT TP1, TP7 TP2, TP3, TP4, TP5, TP6, TP8, TP9, TP10, TP11 Line Item 11 12 13 14 15 16 Part Description Capacitor, Elect., 47µF, 35V, 20%, KS Type Capacitor, Elect., 22µF, 10V, 20%, KS Type Capacitor, Ceramic, .47µF, 16V, 10% Capacitor, Ceramic, X5R, 1µF, 25V, 10%, Capacitor, Ceramic, 4700pF, 50V, 10%, Capacitor, Ceramic, 2200pF, 50V, 10% Manufacturer & Part # PANASONIC PANASONIC PANASONIC PANASONIC PANASONIC PANASONIC ECEA1VKS470i ECEA1AkS220i ECJ2YB1C474K ECJ-2FB1E105K ECJ-1VB1H472K ECJ-1VB1H222K Case Thru Thru 0805 0805 0603 0603 Reference Designators C1 C2 C3, C4, C5, C6 C7, C8, C9, C10, C11, C12, C13, C14, C15, C16 C17, C19, C21, C23 C18, C20, C22, C24 Qty 1 1 4 10 4 4 RESISTORS Line Item 17 18 Part Description Resistor, 25.5K Ohm, 1/10W, 1% Resistor 470 Ohm, 1/10W, 5% Manufacturer & Part # PANASONIC PANASONIC ERJ3EKF2552V ERJ3GSYJ471 Case 0603 0603 Reference Designators R1 R2, R3, R4, R5, R6, R7, R8, R9 Qty 1 8 Copyright © 2004 Rev.1.2, 2007-01-05 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 13 LX1708 TM ® 15+15W Stereo Filterless Class-D Amplifier P RODUCTION D ATA S HEET THD VS PWR @ 4 OHM WITH DIODES THD VS PWR @ 4 OHM NO DIODES W WW . Microsemi . C OM THD+N VS. FREQUENCY 100 50 20 10 5 2 1 0.5 % 0.2 0.1 0.05 0.02 0.01 0.005 0.002 0.001 20 GAIN RESPONSE PVDD = 12V, V5V = 5V PO = 1W, 10Hz ~ 22KHz BPF Load 4 Without Diodes With Diodes See Note 1 on Schematic 50 100 200 500 Hz 1k 2k 5k 10k 20k C CHARTS Copyright © 2004 Rev.1.2, 2007-01-05 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 14 LX1708 TM ® 15+15W Stereo Filterless Class-D Amplifier P RODUCTION D ATA S HEET NOISE FLOOR & SIGNAL-TO-NOISE RATIO CHANNEL CROSSTALK W WW . Microsemi . C OM OUTPUT POWER BANDWIDTH @ 1% THD 100% EFFICIENCY @ 4 OHM LOAD Without LC Filter 90% 80% With LC Filter 70% Efficiency (%) 60% 50% 40% 30% 20% 10% 0% 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Power/CH (W) C CHARTS Copyright © 2004 Rev.1.2, 2007-01-05 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 15 LX1708 TM ® 15+15W Stereo Filterless Class-D Amplifier P RODUCTION D ATA S HEET IQQ VS. FREQUENCY 40 35 30 25 IQQ (mA) 20 15 10 5 0 150k 250k 350k 450k 550k 650k 750k 850k 950k 1,050k 1,150k PSRR (AC) W WW . Microsemi . C OM SW Freq. (Hz) IQQ VS. SUPPLY 35 30 16 20 18 POWER VS. SUPPLY VOLTAGE 25 IQQ (mA) 20 15 10 5 0 Power/CH (W) With LC Filter 4OHM Resistor Load 14 12 10 8 6 R=4ohm; FIN = 1kHz THD+N