NJM2706 3D Surround Audio Processor with Dynamic Bass Boost GENERAL DESCRIPTION The NJM2706 is the 3D surround audio processor with dynamic bass boost, regenerates rich sound field with only small two speakers. The NJM2706 performs NJRC original surround technology realizing natural surround sound field regarded center orientation and NJRC original dynamic bass boost technology provides graceful bass sound with low distortion. It is suitable for mini-component, CD radio-cassette, TV, speaker system and others. PACKAGE OUTLINE NJM2706VE1 FEATURES Operating Voltage +4.7V to +13.0V Wide Dynamic Range 3.1Vrms typ. Low Output Noise 8.9Vrms typ. "eala" 3D Surround Function (Stereo only) Dynamic Bass Boost Function High Frequency Compensation (f=10kHz, GV=+3dB) Variable Surround Effect by external resistor Internal Mode Control Switch Bipolar Technology Package Outline SSOP24-E1 BLOCK DIAGRAM 24 22 20 21 19 18 17 16 15 14 13 50K 23 L HP SW 50K H 50K Vref H 3D FILTER LPF SW SW H:eala L:BYPASS L H VC SW H:eala_Bass L:BYPASS SW L HP 50K H 1 SW L 2 3 4 5 6 7 8 9 10 11 12 -1- NJM2706 PIN CONFIGURATION -2- 1 24 2 23 3 22 4 21 5 20 6 19 7 18 8 17 9 16 10 15 11 14 12 13 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. LPF MIN MOUT Ca Cr BASSFIL1 BASSFIL2 BASSVRIN BASSVROUT ealaVRIN ealaVROUT GND 13. V+ 14. VREFOUT 15. VREFIN 16. SW1 17. SW2 18. ealaFIL 19. HFFILL 20. HFFILR 21. ROUT 22. LOUT 23. RIN 24. LIN NJM2706 ABSOLUTE MAXIMUM RATING (Ta=25C) PARAMETER SYMBOL RATINGS + Supply Voltage V Power Dissipation PD Operating Temperature Range Storage Temperature Range UNIT 15 V (SSOP24) 600 mW Topr -40 to +85 C Tstg -40 to +125 C OPERATING VOLTAGE PARAMETER Operating Voltage SYMBOL TEST CONDITION MIN TYP MAX UNIT V+ - 4.7 12.0 13.0 V MIN TYP MAX UNIT ELECTRICAL CHARACTERISTICS (Ta=25C, V+=12V unless otherwise specified) TEST CONDITION PARAMETER Operating Current Reference Voltage INPUT SYMBOL ICC Vref No Signal No Signal OUT MODE eala Bass L R PUT VR VR 0 0 - Bypass - - - 15.4 23.0 0 0 - Bass MAX - - 15.4 23.0 0 0 - - - - 5.8 6.0 6.2 V UNIT mA + AC CHARACTERISTICS (Ta=25C, V =12V, VIN=-20dBV(100mVrms) unless otherwise specified) TEST CONDITION PARAMETER Maximum Input Voltage Output Noise Total Harmonic Distortion VIM VNO THD MIN TYP MAX - 10.0 (3.2) 12.0 (4.0) - MAX - - 6.0 (2.0) - eala - MAX - 7.9 (2.5) - L R eala Bass MAX MAX 7.8 (2.5) 9.8 (3.1) - VIN L R eala Bass MAX MAX 3.4 (1.5) 5.4 (1.9) - 0 0 L R Bypass - - - -110 (3) -100 (10) 0 0 L R Bass MAX - - -98 (13) - eala - MAX - -100 (10) - INPUT SYMBOL eala Bass VR VR Bypass - *1 Bass VIN L R VIN - VIN f=100Hz THD=3% VIN - Rg=0 A-Weighted Rg=0 A-Weighted OUT L R PUT f=1kHz THD=3% VIN - VIN L R f=100Hz THD=3% VIN VIN f=1kHz THD=3% VIN - f=10kHz THD=3% MODE Rg=0 A-Weighted 0 0 L R Rg=0 A-Weighted 0 0 L R eala Bass MAX MAX - -97 (14) -92 (25) f=1kHz VIN - VIN L R Bypass - - - 0.005 0.01 f=100Hz VIN VIN VIN VIN L R Bass MAX - - 0.05 - f=1kHz VIIN - VIN L R eala - MAX - 0.05 - f=1kHz VIN - VIN L R eala Bass MAX MAX - 0.05 0.5 dBV (Vrms) dBV (Vrms) % *1:BASSVR2OUT -3- NJM2706 + AC CHARACTERISTICS (Ta=25C, V =12V, VIN=-20dBV(100mVrms) unless otherwise specified) TEST CONDITION PARAMETER SYMBOL Bypass Gain GVBYP eala Gain Geala INPUT OUT MODE eala Bass VR VR MIN TYP MAX UNIT dB L R PUT f=1kHz VIN - VIN L R Bypass - - -1.0 0.0 1.0 f=100Hz VIN VIN VIN VIN L R Bass MAX - 4.4 6.4 8.4 f=100Hz VIN VIN VIN VIN L R Bass MIN - -2.0 0.0 2.0 f=1kHz VIN - VIN L R eala - MAX 2.1 4.1 6.1 f=1kHz VIN - VIN L R eala - MIN -2.0 0.0 2.0 f=100Hz VIN - VIN L R eala Bass MAX MAX 5.9 7.9 9.9 f=10kHz VIN - VIN L R eala Bass MAX MAX 0.0 2.0 4.0 MIN TYP MAX dB + CONTROL CHARACTERISTICS (Ta=25C, V =12V, unless otherwise specified) PARAMETER MODE Select Control Voltage TEST CONDITION SYMBOL VMODE VIN=High Level 2.0 - V VIN=Low Level 0.0 - 0.7 SWITCH FUNCTION MODE SW2 SW1 Bypass eala Bass eala Bass L L H H L H L H -4- NOTES Input Through 3D Surround mode Bass Enhanced mode 3D Surround and Bass Enhanced mode UNIT + V NJM2706 !TERMINAL DESCRIPTION No. SYMBOL FUNCTION EQUIVALENT CIRCUIT 1 LPF V+ 16k V+ VOLTAGE Capacitor terminal for LPF V+/2 150 V+ MIN V+ 20k 2 V+ Monaural Amplifier Input V+/2 150 MOUT 50 V+/2 Monaural Amplifier Output 50 3 10k V+ 16k V+ V+ Ca Cr Capacitor Terminal for Attack Time Constant Capacitor Terminal for Release Time Constant 0V 100 10k 4 5 V+ V+ V+ V+ 6 BASSFIL1 82k 10k VCA 0V BASS Filter Terminal 1 150 -5- NJM2706 !TERMINAL DESCRIPTION No. SYMBOL FUNCTION EQUIVALENT CIRCUIT V+ BASS Filter Terminal 2 Rch Output Lch Output 50 BASSFIL2 ROUT LOUT V+ V+/2 50 7 21 22 V+ V+ 8 BASSVRIN BASS Effect Adjust Terminal BASSVROUT V+ V+/2 150 V+ V+ 20k V+ 9 BASS Effect Adjust Terminal V+/2 150 eala Effect Adjust Terminal V+/2 150 ealaVROUT 10k eala Effect Adjust Terminal V+/2 50 11 V+ 20k V+ 50 ealaVRIN V+ 20k V+ 10 -6- VOLTAGE NJM2706 !TERMINAL DESCRIPTION No. SYMBOL FUNCTION EQUIVALENT CIRCUIT 12 GND GND Terminal 0V 13 V+ Power Supply Terminal V+ V+ V+ 50 V+ VOLTAGE 14 VREFOUT Reference Voltage Output V+/2 50 400 V+ VREFIN Reference Voltage Input 50k 15 V+ SW1 SW2 Mode Switch 1 Mode Switch 2 V+ V+/2 400 V+ 0V 150 150k 16 17 V+ 50k V+ -7- NJM2706 !TERMINAL DESCRIPTION No. SYMBOL FUNCTION EQUIVALENT CIRCUIT V+ 32k V+ VOLTAGE 18 ealaFIL eala Filter Terminal V+/2 10k V+ 19 20 HFFILL HFFILR V+ 15k High Frequency Filter for Lch High Frequency Filter for Rch V+/2 400 V+ RIN LIN Rch Input Lch Input VREF -8- V+ V+/2 150 50k 23 24 V+ Min SW2 SW1 BASSVRIN BASSVROUT ealaVRIN 20KB BassVR 14 1 2 3 4 5 6 7 8 9 10 11 V+ 15 GND 16 VREFOUT 17 ealaVROUT ealaFIL BASSFIL2 18 VREFIN HFFILL BASSFIL1 19 Min HFFILR Cr 20 Max Max 20K R2 0.18 F 10 F C4 ROUT Ca 21 1 F C3 RIN LOUT LIN MOUT 22 MIN 23 LPF 24 C2 20K 0.1 F R1 C1 C11 100 F C17 12V 10 F 1 F C5 10 F C6 10 F R3 C7 10K C8 10K ealaSW BassSW Rch Output Lch Output Rch Input Lch Input 30K 560pF C9 0.0047 F R4 30K 560pF R5 C10 R6 10 F 10 F C12 10 F C13 10 F C15 C16 NJM2706 APPLICATION CIRCUIT 13 12 20KB ealaVR -9- NJM2706 APPLICATION NOTE 1. Fine-Tuning the ealaBASS The NJM2706 has quite sophisticated NJRC's original dynamic bass-boost technology. Both of the level and the frequency for bass-boost moves automatically corresponding to the input signal level. This dynamic filtering action prevents the signals over boosted, and provides less distortion and wide dynamic range bass-boost processing. In addition, if you want to fine-tune the bass-boost effect for your system, you can modify the bass-boost effect by changing the external parts value as described below. 1-1. Modify the Boost Center Frequency This plot shows the frequency response for NJM2706 ealaBASS. Frequency Characteristics (eala Bass) V+=12V Vin=-20dBVLch Vout=Lch RL=4.7k Rg=25 10 C4=0.1F C4=0.15F 5 Gain [dB] C4=0.18F 0 -5 10 100 1000 10 4 10 5 Frequency [Hz] The Boost Center Frequency can be adjusted by changing the value for the external capacitor, C4. If your speaker system has more than 100Hz of f0 (= Lower Frequency Response Range), or, if you would like to get more powerful bass-boost effect than the typical settings shown on the page 9, increasing the Boost Center Frequency higher could be a good idea. We strongly recommend you to determine the actual capacitance value by testing and examinations on your actual application. 1-2. Modification for the LPF Cut-off Frequency fCL This picture shows the equivalent circuit for NJM2706's LPF. R1 20k 20k 2pin Lch 3pin LPF 20k Rch 16k MONO Amp. 1pin C1 0.1 The LPF Cut-off Frequency fCL is given by the following equation: 1 1 fCL= 2CR = 2C1x16k Set the fCL as same as the Boost Center Frequency, which is determined as above (The Boost Center Frequency = the frequency of which the gain is +3dB). In the typical application circuit shown on the page 9, the LPF Cut-off Frequency fCL is set to 100Hz. - 10 - NJM2706 REFERENCE VALUE C1[ F] C4[ F] Large(f=100Hz)*) 0.1 0.18 Speaker Size Medium(f=150Hz) 0.068 0.15 Small(f=200Hz) 0.047 0.1 *) default value 1-3. Adjusting the Summing Level for ealaBASS effect to L/R Output Signal Changing the resistance value connected between the terminal 8 and 9 can modify the Summing Level for the ealaBASS effect to the L/R Output Signal. 2. Adjusting the High Frequency Compensation Filter The NJM2706 has High Frequency Compensation Filter, which can produce well balance between boosted-bass frequency range and treble frequency range. This picture shows the equivalent circuit for the High Frequency Compensation Filter. 15k 20pin HFFIL R6 30k C11 560p The Cut-off Frequency fCH and the Voltage Gain GVH are defined as below: fCH= 1 = 2CR 1 2xC11xR6 GVH= 20log R6+15k R6 In the typical application circuit shown on the page 9, the High Frequency Compensation Filter Cut-off Frequency fCH is set to 10kHz and Voltage Gain GVH is set to 3.5dB. - 11 - NJM2706 3. Fine-Tuning eala(surround) Changing the external parts value modifies the eala surround effect as described below. 3-1.Adjust the Cut-off frequency Plot below Shows Voltage gain vs. Frequency. eala effect depends on C9 value. Changing C9 value controls eala filter cut-off frequency fCL. . Initial fcl is 1kHz. After trial listening, decide appropriate C9 value. Surround frequency becomes higher by smaller value. Gain vs.Frequency o V+=12V,Vin=-10dB,Vout=Lch,Ta=25 V+=12V,Vin=-10dBV,Vout=Lch,Ta=25 C 14 C9=0. 0082F 20k 12 LPF [dB] 32k Rch 20k 20k C9 0.0047 C9=0. 0027F 10 20k Lch C9=0. 0047F eala FILpin Gain [dB] 8 6 4 LPF circuit 2 1 fCL(Cut-off Frequency)= 1 2 CR = 0 2 C1x x32k 10 100 1000 [Hz] Frequency [Hz] 3-2Adjust eala gain Surround VR value (10pin) controls eala gain. Typical value is 20k. Surround effect becomes stronger by larger value. Gain vs Frequency V+=12V, Vin=-10dBV, Vout=Lch Output, Ta=25C 12 11 10 Surround VR=50k 9 Gain [dB] 8 7 6 Surround VR=20k 5 4 Surround VR=10k 3 2 Surround VR=5k 1 0 10 Surround VR=0 100 1000 Frequency [Hz] - 12 - 10000 100000 10000 100000 NJM2706 TYPICAL CHARACTERISTICS Supply Current vs. Supply Voltage Supply Current vs. Temperature V+=12V V+=1-13V, Ta=25 oC 16 20 BASS eala BASS Bypass 15 Supply Current [mA] Supply Current [mA] 15 BASS eala 10 Bypass 14 13 12 5 11 10 0 0 5 10 15 -50 20 0 150 Temperature [ C] Maximum Input Voltage vs. Supply Voltage (BASS) Maximum Input Voltage vs. Supply Voltage (Bypass) Vin=Lch+Rch, Vout=BASSVROUT, f=100Hz, RL=4.7k , Vin=Lch, Vout=Lch, f=1kHz, RL=4.7k , Rg=25 , Ta=25 oC Rg=25 , Ta=25 oC 20 20 15 15 Maximum Input Voltage [dBV] Maxmum Input Voltage [dBV] 100 o Supply Voltage [V] 10 5 0 -5 10 5 0 -5 -10 -10 0 4 8 12 0 16 4 8 12 16 Supply Voltagte [V] Supply Voltage [V] Maximum Input Voltage vs. Supply Voltage (eala) Maximum Input Voltage (eala BASS) Vin=Lch, Vout=Lch, f=1kHz, RL=4.7k , Vin=Lch, Vout=Lch, f=10kHz, RL=4.7k , Rg=25 , Ta=25 oC Rg=25 , Ta=25 oC 15 15 10 10 Maximum Input Voltage [dBV] Maximum Input Voltage [dBV] 50 5 0 -5 5 0 -5 -10 -10 -15 -15 0 4 8 12 Supply Voltage [V] 16 0 4 8 12 16 Supply Voltage [V] - 13 - NJM2706 TYPICAL CHARACTERISTICS Maximum Input Voltage vs. Supply Voltage (eala BASS) Vin=Lch+Rch, Vout=Lch, f=100Hz, RL=4.7k , Output Noise vs. Temperature V+=12V, Vin=GND, Vout=Lch 15 -90 10 -95 5 -100 Output Noise [dBV] Maximum Input Voltage [dBV] Rg=25 Ta=25 oC 0 eala BASS BASS eala -105 -110 -5 Bypass -115 -10 -120 -15 0 4 8 12 -50 16 0 50 150 Temperature [ C] Supply Voltage [V] THD+N vs. Input Voltage (Bypass) THD+N vs. Input Voltage (Bypass) V+=12V, Vin=Lch, Vout=Lch, f=1kHz, RL=4.7k , Rg=25 , BW=10-80KHz V+=12V, Vin=Lch, Vout=Lch, f=100Hz, RL=4.7k , Rg=25 , BW=10-80kHz 10 100 o 10 1 1 Ta=85oC Ta=25oC 0.1 0.1 THD+N [%] THD+N [%] Ta=85oC Ta=-40oC 0.01 Ta=25oC Ta=-40oC 0.01 0.001 0.001 0.0001 0.0001 -50 -40 -30 -20 -10 0 10 -50 20 -40 -30 Input Voltage [dBV] -10 0 10 20 Input Voltage [dBV] THD+N vs. Input Voltage (eala) THD+N vs. Input Voltage (Bypass) V+=12V, Vin=Lch, Vout=Lch, f=1kHz, RL=4.7k , Rg=25 , BW=10-80kHz V+=12V, Vin=Lch, Vout=Lch, f=10kHz, RL=4.7k , Rg=25 , BW=10-80kHz 10 -20 10 1 Ta=-40oC THD+N [%] THD+N [%] 1 Ta=85oC 0.1 o Ta=25 C Ta=25oC Ta=85oC Ta=-40oC 0.1 0.01 0.001 0.01 -50 -40 -30 -20 -10 Input Voltage [dBV] - 14 - 0 10 20 -50 -40 -30 -20 -10 Input Voltage [dBV] 0 10 20 NJM2706 TYPICAL CHARACTERISTICS THD+N vs. Input Voltage (eala BASS) THD+N vs. Input Voltage (eala BASS) V+=12V, Vin=Lch, Vout=Lch, f=100Hz, RL=4.7k , Rg=25 , BW=10-80kHz V+=12V, Vin=Lch, Vout=Lch, f=1kHz, RL=4.7k , Rg=25 , BW=10-80kHz 10 10 1 THD+N [%] THD+N [%] 1 o Ta=85 C Ta=25oC Ta=-40oC 0.1 Ta=-40oC Ta=25oC Ta=85oC 0.1 0.01 0.01 -50 -40 -30 -20 -10 0 10 20 -50 -40 -30 Input Voltage [dBV] -20 -10 0 10 20 Input Voltage [dBV] THD+N vs. Input Voltage (eala BASS) Gain vs. Frequency (Bypass) V+=12V, Vin=Lch, Vout=Lch, f=20kHz, RL=4.7k , Rg=25 , BW=10-80kHz V+=12V, Vin=-20dBV Lch, Vout=Lch, RL=4.7k , Rg=25 3 10 2 Ta=85oC 1 Ta=25oC 1 Gain [dB] THD+N [%] Ta=-40oC Ta=-40oC Ta=25oC Ta=85oC 0.1 0 -1 -2 0.01 -3 -50 -40 -30 -20 -10 0 10 20 10 100 Input Voltage [dBV] Gain vs. Frequency (BASS) 10 10 8 Gain [dB] Gain [dB] 10 5 Ta=85oC Ta=25oC Ta=-40oC 4 6 2 0 0 -2 10 4 10 5 Ta=25oC Ta=-40oC 4 2 Frequency [Hz] 5 8 Ta=85oC 1000 10 Gain vs. Frequency (eala) 12 100 4 V+=12V, Vin=-20dBV Lch, Vout=Lch, RL=4.7k , Rg=25 12 10 10 Frequency [Hz] V+=12V, Vin=-20dBV Lch+Rch, Vout=Lch, RL=4.7k , Rg=25 6 1000 -2 10 100 1000 10 4 Frequency [Hz] - 15 - NJM2706 TYPICAL CHARACTERISTICS Gain vs. Frequency (eala BASS) V+=12V, Vin=-20dBV Lch, Vout=Lch, RL=4.7k , Rg=25 Gain vs. Frequency (eala BASS) 20 12 10 15 Ta=85oC 8 Ta=25oC -40dBV INPUT -30dBV INPUT 10 6 Gain [dB] Gain [dB] Ta=-40oC 4 -20dBV INPUT -10dBV INPUT 5 0dBV INPUT 2 0 0 -5 -2 10 100 1000 10 4 10 5 10 100 1000 10 4 Frequency [Hz] Frequency [Hz] [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. - 16 - Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: NJR: NJM2706L NJM2706VE1-TE2 NJM2706E2-TE1