NJU8710 PRELIMINARY 2V Operation Clock-less Switching Driver for Class D Amplifier PACKAGE OUTLINE GENERAL DESCRIPTION The NJU8710 is a 2V operation clock-less switching driver for a class D Amplifier with separated power supply between Input and Output. The NJU8710 provides powerful drivability in both of sink and source without flow-through current. Therefore, it can be used to the buffer or the switch as a driver IC. Furthermore it converts 1bit digital signal input, such as PWM or PDM signal, to analog signal output of the hi-fi audio level through a simple external LC low-pass filter. The NJU8710 realizes very high power-efficiency because of the class D operation and low voltage operation. Therefore, it is suitable for battery powered applications and others. NJU8710R PIN CONFIGURATION FEATURES 2-channel 1bit Digital Signal Input Standby(Hi-Z) Control function Operating Voltage : 1.7V to 2.7V Driving Voltage : 1.7V to VDD CMOS Technology Package Outline : VSP10 STBYB IN1 VSS OUTX1 VDDO 10 9 8 7 6 1 2 3 4 5 VDD IN2 VSS OUTX2 VDDO BLOCK DIAGRAM VDD VDDO VSS OUTX1 IN2 Dead Time Generator IN1 OUTX2 STBY Ver.2004-06-02 VDDO VSS -1- NJU8710 TERMINAL DESCRIPTION No. 10 SYMBOL VDD I/O − Function 5 6 VDDO − Output Power Supply: VDDO=2V 3 8 VSS − Power GND and Output GND terminal: VSS=0V 2 9 IN1 IN2 I 1-bit Data Input Terminal Power Supply: VDD=2V Output Terminal OUTX1 terminal outputs the inverted signal of IN1 terminal, OUTX2 terminal outputs the inverted signal of IN2 terminal. 1 STBYB I Standby Control Terminal (L:Standby) *VSS(Terminal No.3,8) should be connected at a nearest point to the IC. *VDDO(Terminal No.5,6) should be connected at a nearest point to the IC. *STBYB(Terminal No.1) must be connected to VDD, when this function is not used. 4 7 OUTX1 OUTX2 O INPUT TERMINAL STRUCTURE VDD Input Terminal IC Circuit VSS FUNCTIONAL DESCRIPTION (1) Signal Output (OUTX1, OUTX2 Terminal) Output signal becomes a inverted input signal. A flow-through current at the signal polarity transition doesn't generate by optimized dead time control circuit. Output signal is converted to analog signal via external 2nd-order or higher LC filter. A switching regulator with a high response against a voltage fluctuation is the best selection for the VDDO, which is the power supply for output drivers. To obtain better T.H.D. performance, the stabilization of the power is required. (2) Standby Control Function By setting the STBYB terminal to “L”, the NJU8710 becomes standby condition. OUTX1 and OUTX2 are in Hi-Z. -- 2 2 -- During standby condition, Ver.2004-06-02 NJU8710 NJU3555 ABSOLUTE MAXIMUM RATINGS PARAMETER (Ta=25°C) UNIT SYMBOL RATING VDD -0.3 to +4.0 V VDDO -0.3 to +2.7 V Input Voltage Vin -0.3 to VDD+0.3 V Operating Temperature Topr -40 to +85 °C Storage Temperature Tstg -40 to +125 °C PD 450* mW - VDD ≥ VDDO V Supply Voltage Power Dissipation VSP10 Power Supply Voltage Condition * : Mounted on two-layer board of based on the JEDEC. Note 1) All voltage values are specified as VSS=0V. Note 2) If the LSI is used on condition beyond the absolute maximum rating, the LSI may be destroyed. Using LSI within electrical characteristics is strongly recommended for normal operation. Use beyond the electrical characteristics conditions will cause malfunction and poor reliability. Note 3) De-coupling capacitors should be connected between VDD-VSS and VDDO-VSS due to the stabilized operation. ELECTRICAL CHARACTERISTICS PARAMETER SYMBOL (Ta=25°C, VDD=VDDO=2.0V, VSS=0.0V, unless otherwise noted) CONDITIONS MIN. TYP. MAX. UNIT VDD Supply Voltage VDD 1.7 2.0 2.7 V VDDO Supply Voltage VDDO 1.7 2.0 VDD V Output Driver High side Resistance RH VOUT=VDDO-0.1V - 1.5 2 Ω Output Driver Low side Resistance RL VOUT=0.1V - 1.5 2 Ω Operating Current at Hi-Z Output IST IN1, IN2, STBYB=”L” - - 1 µA Operating Current at no input signal IDD IDDO No-load operating, IN1=IN2=1.4MHz - 0.05 0.6 T.B.D T.B.D mA VDD V VIH 0.7VDD - VIL 0 - 0.3VDD V ILK - - ±1 µA Input Voltage Input Leakage Current Ver.2004-06-02 -3- NJU8710 TIMING CHARACTERISTICS • Signal Spread Characteristics IN1, IN2 0.7VDD 0.3VDD tPDH tPDL 0.7VDD OUTX1, OUTX2 • 0.3VDD (Ta=25°C, VDD=VDDO=2.0V, VSS=0.0V unless otherwise noted) CONDITIONS MIN. TYP. MAX. UNIT PARAMETER SYMBOL Maximum Operating Frequency fMax - - 25 MHz Signal Spread Time (H → L) tPDL - - 20 ns Signal Spread Time (L→ H) tPDH - - 20 ns Output Control Signal Input (STBYB) STBYB 0.7VDD 0.7VDD 0.3VDD 0.3VDD tUP PARAMETER -- 4 4 -- SYMBOL tDN (Ta=25°C, VDD=VDDO=2.0V, VSS=0.0V unless otherwise noted) CONDITIONS MIN. TYP. MAX. UNIT Rise Time tUP - - 50 ns Fall Time tDN - - 50 ns Ver.2004-06-02 NJU8710 NJU3555 APPLICATION CIRCUIT (Analog Signal Output) • A914BY-101M is manufactured by TOKO, INC. Stereo OTL application example 220µF A914BY-101M OUTX1 4 100µH Audio Signal Standby Control 1 IN2 STBYB 220µF A914BY-101M OUTX2 7 VDDO 10µF 0.1µF 10 VDDO VDD VSS • 1kΩ 100µH VSS Logic Power 32Ω Headphone NJU8710 9 1kΩ IN1 0.22µF 2 For further information, please refer to its technical papers. 0.22µF • 0.1µF 5 0.1µF 47µF 3 Switching Regulator 0.1µF 6 8 • A914BY-101M is manufactured by TOKO, INC. Monaural BTL application example For further information, please refer to its technical papers. Standby Control 1 IN2 STBYB OUTX1 4 100µH OUTX2 7 VDDO VSS 10µF 0.1µF 10 Logic Power VDD 100µH VDDO VSS 32Ω Speaker 0.22µF 9 IN1 NJU8710 2 0.22µF A914BY-101M Audio Signal A914BY-101M 0.1µF 5 0.1µF 3 47µF Switching Regulator 0.1µF 6 8 Note 4) De-coupling capacitors must be connected between each power supply terminal and GND terminal. Note 5) The power supply for VDDO requires fast driving response performance such as a switching regulator for T.H.D.. Note 6) The bigger capacitor value of external AC-coupling capacitors realize better low frequency response characteristics. In addition, ESR(Equivalent Series Resistance) should be low. Note 7) The above circuit shows only application example and does not guarantee the any electrical characteristics. Therefore, please consider and check the circuit carefully to fit your application. Ver.2004-06-02 -5- NJU8710 [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. -- 6 6 -- Ver.2004-06-02