Preliminary NJU8758 Analog Signal Input Monaural 1.5W Filterless Class D Power Amplifier PACKAGE OUTLINE GENERAL DESCRIPTION The NJU8758 is an analog signal input monaural 1.5W filterless class D power amplifier. The NJU8758 is capable of driving 0.6W at 3.3V or 1.5W at 5.0V into 8ohms without external LC low-pass filters. It includes an output-short protector. The NJU8758 incorporates BTL amplifier, which eliminate AC coupling capacitors. The NJU8758 features high power-efficiency by class-D operation, and is suited for security equipment, portable set with speaker, PC, etc. NJU8758V FEATURES Operating Voltage: 1.8 to 5.5V 1.5 W at 5V into 8ohms No output filters Standby(Hi-Z), Mute Control Built-in Pop noise reduction EQ for Active filter Built-in Low Voltage Detector Built-in Short Protector for each channel CMOS Technology Package Outline: SSOP14 PIN CONFIGURATION Ver.2009-11-10 VDD 1 14 OUTTEST IN 2 13 VSS EQ1 3 12 OUTP EQ2 4 11 VDDO COM 5 10 OUTN MUTEb 6 9 VSS STBYb 7 8 TEST -1- NJU8758 BLOCK DIAGRAM EQ1 VDD EQ2 VDDO OSCILLATOR IN LEVEL SHIFTER OUTP PULSE WIDTH MODULATOR COM LEVEL SHIFTER BIAS TEST SHORT PROTECTION SOFT START VDD LOW BAT. PROTECTION CONTROL LOGIC OUTN VDDO LOW BAT. PROTECTION VSS STBYb MUTEb VSS PIN DESCRIPTION No SYMBOL I/O FUNCTION 1 VDD - Power supply : VDD=3.3V (*1) 2 IN I Signal input 3 EQ1 I/O for Active filter 4 EQ2 I/O for Active filter 5 COM - Analog common Mute control (*3) 6 MUTEb I MUTEb=Low: MUTE Mode Standby control (*3) 7 STBYb I STBYb=MUTEb=Low: Standby Mode 8 TEST I TEST terminal for maker (*4) 9 VSS Power GND : VSS=0V (*1)(*2) 10 OUTN O Negative output 11 VDDO Output power supply : VDDO =3.3V (*1) 12 OUTP O Positive output 13 VSS Power GND : VSS=0V (*1)(*2) 14 OUTTEST O Short Detect output *1) The relations of ”VSS= 0V” and “VDD= VDDO” must be maintained. *2) The VSS should be connected at a nearest point to the IC. *3) The MUTEb and the STBYb must be connected to VDD, when these terminals are not used. *4) The Test terminal must be connected to VSS. -2- Ver.2009-11-10 NJU8758 NJU3555 FUNCTIONAL DESCRIPTION (1) Signal Output (OUTP, OUTN) The OUTP and OUTN generate PMW output signal. (2) Standby (STBYb) By setting the STBYb and MUTEb terminal to “L”, the standby mode is enabled. In the standby mode, the entire functions of the NJU8758 enter a low-power state, and the output terminals(OUTP and OUTN) are in high impedance. (3) Mute (MUTEb) By setting the MUTEb terminal to “L”, the Mute function is enabled, and the output terminals(OUTP and OUTN) output square wave(Duty: 50%). The NJU8758 has a built-in circuit for the pop-noise reduction at power-on. However the control with the sequence can realize more effective the pop-noise reduction. VDD,VDDO STBYb MUTEb over 100 ms Timing for pop-noise reduction Ver.2009-11-10 -3- NJU8758 (4) EQ for Active filter (IN, EQ1, EQ2) The NJU8758 has EQ1 and EQ2, which is for active filter. The band-pass filter is calculated as shown below. RS1 CS1 CF1 RF1 CF2 EQ1 EQ2 RS=27 kΩ RF=32 kΩ NJU8758 RF CC RS + IN VIN Example: The band-pass filter 1 1 1 + sC F2 + RF ⎛ 1 ⎞ ⎟ ⎜ R + F1 ⎟ ⎜ sC F1 ⎠ ⎝ H(s ) = − 1 1 + 1 1 sC C + 1 RS + R S1 sC S1 CF1>100 pF (5) Low Voltage Detector When the power supply voltage drops down to below VDD(MIN), the internal circuit is halted, and the output terminals(OUTP and OUTN) become in high impedance. (6) Short Protection Circuit The short protector is enabled in response to following accidents. Short between OUTP and OUTN Short between OUTP and VSS Short between OUTN and VSS When the Short Protector enable, the output terminals (OUTP and OUTN) become in high impedance, and OUTTEST enable” H”(H=VDD). By setting the STBYb terminal to “L”, the NJU8758 returns to normal operation. Note 1) The detectable current and the period for the protection depend on the power supply voltage and ambient temperature. Note 2) The short protector is not effective for a long term short-circuit but for an instantaneous accident. Continuous high-current may cause permanent damage to NJU8758. -4- Ver.2009-11-10 NJU8758 NJU3555 ABSOLUTE MAXIMUM RATINGS PARAMETER Supply Voltage Input Voltage Operating Temperature Storage Temperature TERMINAL VDD VDDO IN, STBYb, MUTEb SYMBOL VDD VDDO Vin (Ta=25°C) RATING -0.3 to +7.0 -0.3 to +7.0 -0.3 to VDD + 0.3 UNIT V V V Ta -40 to +85 °C Tstg -40 to +125 °C Mounted on two-layer board of based on the EIAJ, 450 mW Power Tj = 125°C Dissipation Mounted on four-layer board of based on the EIAJ, PDMAX4 570 mW Tj = 125°C Mounted on two-layer board of based on the EIAJ, θja2 223 °C /W Tj = 125°C Thermal Resistance Mounted on four -layer board of based on the EIAJ, θja4 176 °C /W Tj = 125°C Note 3) All voltage are relative to “VSS= 0V” reference. Note 4) Mounted on two-layer/4-layer board of based on the EIA/JEDEC STD Note 5) The IC must be used inside of the “Absolute maximum ratings”. Otherwise, a stress may cause permanent damage to the LSI. Note 6) De-coupling capacitors for VDD-VSS and VDDO-VSS should be connected for stable operation. Note 7) The class-D amplifiers are more power efficient, and dissipate power less than general analog-amplifiers. In theory, the NJU8758 actualize quite high output-power such as 1.2W at =5V operation with 8ohms load, it looks as if the NJU8758 exceeds the absolute maximum rating of the power dissipation. However, in practice, the effective output-power of usual music sound is only about 1/10 of its maximum output power, thus it may never exceed the absolute maximum rating. PDMAX2 The maximum power dissipation in the system is calculated, as shown below. PDMAX = T jMAX [°C ] − Ta [°C ] θ ja [°C / W ] Pdmax: Maximum Power Dissipation, Tjmax: Junction Temperature = 125°C Ta: Ambient Temperature, θja: Thermal Resistance of package (SSOP14) = 223°C/W Power dissipation of the NJU8758 itself is calculated, as shown below. PD = Ver.2009-11-10 125°C − 50°C = 336.3mW 223°C / W -5- NJU8758 ELECTRICAL CHARACTERISTICS (7) DC CHARACTERISTICS (Ta=25°C, VDD=VDDO= 3.3V, VSS= 0V, Input Signal=1kHz, Input Signal Level=200mVrms, Load Impedance=8Ω) PARAMETER SYMB OL VDD,VDDO Supply Voltage VDD, VDDO Drain-Source On-state Resistance (High-side) Drain-Source On-state Resistance (Low-side) Input Impedance CONDITIONS MIN. TYP. MAX. UNIT 1.8 3.3 5.5 V RONH OUTP, OUTN VOUTP,N = VDDO - 0.1 V - 0.5 - Ω RONL OUTP, OUTN VOUTP,N = 0.1 V - 0.5 - Ω RIN IN - 27 - kΩ - 0.1 0.5 µA - 0.1 0.5 µA - 1.5 - mA - 1.2 - mA IST Operating Current (Standby) ISTO VDD, STBYb: "L", No Load VDDO, STBYb: "L", No Load IDD Operating Current (No signal input) No Load IDDO VIH STBYb, MUTEb 1.5 - VDD V VIL STBYb, MUTEb 0 - 0.5 V Input Leakage Current ILK STBYb, MUTEb - - ±1 µA Frequency fOSC - 320 - kHz Start up Time TON MUTEb: "L" - 205 - ms Voltage Gain AV No Load - 22.9 - dB Input Voltage -6- Ver.2009-11-10 NJU8758 NJU3555 (8) AC CHARACTERISTICS (Ta=25°C, VDD= VDDL= VDDR=3.3V, Input Signal=1kHz, Input Signal Level=200mVrms, Load Impedan ce=8Ω,) MIN. TYP. MAX. PARAMETER CONDITIONS SYMBOL UNIT Output Power Efficiency EEFF THD+N=10 % - 80 - % THD+N THD+N PO=200 mW - 0.05 - % VDD=VDDO=3.3 V THD+N=10 % - 0.66 - W VDD=VDDO=5.0 V THD+N=10 % - 1.5 - W A-weight VDD=VDDO=5.0 V - 84 - dB Output Power PO S/N S/N Test system of the output THD NJU8758 AUX-0025 NJU8758 Evaluation Board LPF Filters 20kHz(AES17) THD METER Audio Analyzer Output THD Test System Ver.2009-11-10 -7- NJU8758 TYPICAL APPLICATION CIRCUIT + Battery + 10 µF 1 µF VDDO(11) VDD(1) 10 µF 0.1 µF OUTP(12) 1 µF IN(2) 100 pF EQ2(4) STBYb(7) NJU8758 8Ω EQ1(3) OUTN(10) MUTEb(6) TEST(8) COM(5) 10 µF + VSS(9,13) TYPICAL APPLICATION CIRCUIT Note 8) De-coupling capacitors must be connected between each power supply terminal and GND (VDD-VSS, VDDO-VSS). Note 9) VSS should be connected at a nearest point to the IC on PCB. Note 10) IN, EQ1 and EQ2 should be not designed near OUTP and OUTN, which emit PWM noise. Note 11) The power supply for VDDO requires fast driving response performance such as a switching regulator for better THD. Note 12) The above circuit shows only application example and does not guarantee the any electrical characteristics. Therefore, please test the circuit carefully to fit your application. Note 13) The transition time for MUTEB and STBYB signals must be less than 100µs. Otherwise, a malfunction may be occurred. Note 14) (1) – (12) indicates terminal number. [CAUTION] The specifications on this databook are only given for information , without any guarantee as regards either mistakes or omissions. The application circuits in this databook are described only to show representative usages of the product and not intended for the guarantee or permission of any right including the industrial rights. -8- Ver.2009-11-10