NJM2794 Ground Noise Isolation Amplifier ■ GENERAL DESCRIPTION The NJM2794 is a ground noise isolation amplifier designed for car audio system. It contains dual channel differential amplifier. It is developed for those car audio applications where long connections between head unit and other components are necessary and ground noise has to be eliminated. ■ FEATURES ● Dual Channel Differential Amplifier ● Operating Voltage ● Operating Current ● Common mode rejection ratio ● Maximum Output Voltage ● Supply Voltage Rejection Ratio ● Total Harmonic Distortion ● Noise Output Voltage ● Bipolar Technology ● Package Outline ■ PACKAGE OUTLINE NJM2794RB2 NJM2794V 4.3 to 13V 14mA typ. CMRR=60dB typ. 2Vrms min., @ THD=0.1% 60dB typ. 0.002% typ. 1.3µVrms typ. TVSP10, SSOP14 ■ BLOCK DIAGRAM V+ IN1OUT1 IN1+ Vref IN2+ OUT2 IN2- GND –1– NJM2794 ■ PIN CONFIGURATION TVSP10 No. 1 10 5 6 1 2 3 4 5 6 7 8 9 10 Symbol OUT1 GND Vref V+ OUT2 IN2+ IN2NC IN1IN1+ Function Output1 Ground Reference Voltage Power Supply Output2 +Input2 -Input2 No Connect -Input1 +Input1 SSOP14 –2– 1 14 7 8 No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Symbol OUT1 NC GND Vref V+ NC OUT2 IN2+ NC IN2NC IN1NC IN1+ Function Output1 No Connect Ground Reference Voltage Power Supply No Connect Output2 +Input2 No Connect -Input2 No Connect -Input1 No Connect +Input1 NJM2794 ■ ABSOLUTE MAXIMUM RANGES PARAMETER Supply Voltage (Ta=25°C) SYMBOL RANGE UNIT +15 V + V Maximum Input Voltage VIM Power Dissipation PD +(✴) 0 to V TVSP10 : 530* SSOP14 : 550* V mW NOTE: EIA/JEDEC STANDARD Test board (76.2x114.3x1.6mm, 2layer, FR-4) mounting Operating Temperature Topr -40 to +85 °C Storage Temperature Tstg -40 to +150 °C (✴) For the maximum input voltage less than 0 toV+ + ■ ELECTRICAL CHARACTERRISTIC (V =9V,Ta=25°C) PARAMETER TEST CONDITION SYMBOL MIN. TYP. MAX. UNIT 4.3 9 13 V - 14 20 mA 3.8 4.3 4.8 V DC CHARACTERRISTIC + Operating Voltage V Operating Current ICC Reference Voltage VREF No Signal AC CHARACTERRISTIC (Non-inverting circuit, f=1kHz, Vin=1Vrms, Rg=0Ω, RL=10kΩ unless otherwise specified) Voltage Gain Gv Channel Separation CS Channel Balance BAL f=1kHz 0.0 +1.0 dB 90 110 - dB - - 0.5 dB 100 - - kHz Roll-off High Frequency fRH Input Resistance RIN 85 105 125 kΩ Output Resistance ROUT - 90 - Ω Maximum Output Voltage 1 VOM1 2 2.5 - Vrms 1.7 2.1 - Vrms - 2.5 - Vrms - 2.1 - Vrms - 1.3 2.5 µVrms - 0.002 0.01 % 50 60 - dB - 2 - Vrms 55 65 - dB Maximum Output Voltage 2 VOM2 Maximum Output Voltage 3 VOM3 Maximum Output Voltage 4 VOM4 Noise Output Voltage VNO Total Harmonic Distortion Common Mode Rejection Ratio Common Mode Input Voltage Supply Voltage Rejection Ratio THD -1dB -1.0 THD=0.1%, f = 1kHz + THD=0.1%, f = 1kHz, V =8V Inverting, THD=0.1%, f = 1kHz Inverting, + THD=0.1%, f = 1kHz, V =8V Rg=600Ω, A-weighted f=1kHz , VO=1Vrms, BW=400Hz to 30kHz CMRR Vicm CMRR=50dB SVR f=100Hz , Vripple=100mVrms –3– NJM2794 ! TERMINAL DESCRIPTION TERMINAL DC VOLTAGE PIN NO. TVSP 10 SSOP 14 SYMBOL FUNCTION EQUIVALENT CIRCUIT V+ V+ 1 5 1 7 OUT1 OUT2 Output1 Output2 100Ω 6 7 9 10 8 10 12 14 IN2+ IN2IN1IN1+ +Input2 -Input2 -Input1 +Input1 50Ω FB V+x0.48 [V] V+x0.48 [V] 105kΩ Vref V+ V+ V+ 260kΩ 100Ω 3 4 Vref Reference Voltage V+x0.48 [V] 240kΩ –4– NJM2794 ■ APPLICATION CIRCUIT ● TVSP10 (NJM2794RB2) OUT1 OUT1 1 + IN1+ + 10 3.3μF GND 2 Vref 3 + 10μF IN1+ 0.33μF IN1+ 9 IN1- 0.33μF NC 8 V+ 22μF + V+ IN2- 4 7 OUT2 OUT2 5 + + IN2- 0.33μF IN2+ + 6 IN2+ 0.33μF 3.3μF ● SSOP14 (NJM2794V) OUT1 OUT1 1 + IN1+ 2 GND 3 Vref 4 + 10μF IN1+ 0.33μF 3.3μF NC + 14 NC 13 IN1- 12 + IN1- 0.33μF NC 11 V+ V+ 22μF 5 + NC 6 OUT2 OUT2 + 3.3μF 7 IN2- 10 + IN2- 0.33μF NC 9 IN2+ 8 + IN2+ 0.33μF –5– NJM2794 ■ APPLICATION BLOCK DIAGRAM (1) Non-inverting line input OUT IN+ NJM2794 IN- IC GND Vref VN (2) Inverting line input OUT IN- NJM2794 IN+ VN (3) Non-inverting line output OUT IN+ NJM2794 IN- IC GND Vref VN (4) Inverting line output OUT IN- NJM2794 IN+ IC GND Vref VN –6– IC GND Vref NJM2794 ! TYPICAL CHARACTERISTICS Operating Current vs. Ambient Temperature V+=9V Operating Current vs. Operating Voltage 30 25 25 Operating Current [mA] Operationg Current [mA] 30 20 15 10 20 15 10 -40oC 5 5 0 0 -50 -25 0 25 50 75 100 125 150 0 3 6 Ambient Temperature [oC] 12 15 Reference Voltage vs. Operating Voltage 15 15 12 12 Reference Voltage [V] Reference Voltage [V] 9 Operating Voltage [V] Reference Voltage vs. Ambient Temperature V+=9V 9 6 3 9 6 Ta=85,25,-40oC 3 0 0 -50 -25 0 25 50 75 100 125 150 0 3 6 Ambient Temparature [oC] 9 12 15 Operating Voltage [V] Noise Output Voltage vs. Ambient Temperature V+=9V, Rg=600Ω, A-Weighted Noise Output Voltage vs. Signal Source Resistance V+=9V, Ta=25oC, A-Weighted 0 0 -20 Noise Output Voltage [dBV] Noise Output Voltage [dBV] Ta=85oC 25oC -40 -60 -80 -100 -120 -140 -20 -40 -60 -80 -100 -120 -50 -25 0 25 50 75 100 Ambient Temperature [oC] 125 150 0.01 0.1 1 10 100 Signal Source Resistance [kΩ] –7– NJM2794 ! TYPICAL CHARACTERISTICS Channel Separation vs. Ambient Temperature V+=9V, Rg=600Ω, Vin=1Vrms, BW=400Hz-30kHz Channel Separation vs. Frequency V+=9V, Rg=600Ω, Vin=1Vrms, BW=10Hz-30kHz 0 -20 -20 Channel Separation [dB] Channel Separation [dB] IN1+ -> OUT2 0 -40 -60 -80 -100 -120 -40 -60 -80 -100 IN1+ -> OUT2 IN2+ -> OUT1 -120 -50 -25 0 25 50 75 100 125 150 10 Ambient Temperature [oC] 10000 100000 THD+N vs. Output Voltage V+=9V, f=1kHz, Inverting Circuit 1 1 0.1 0.1 THD+N [%] THD+N [%] 1000 Frequency [Hz] THD+N vs. Output Voltage V+=9V, f=1kHz, Non-Inverting Circuit 0.01 100 Ta=25,85oC 0.01 Ta=-40,25,85oC Ta=-40oC 0.001 0.001 0.01 0.1 1 10 0.01 Output Voltage [Vrms] THD+N vs. Output Voltage V+=8V, f=1kHz, Non-Inverting Circuit 1 10 THD+N vs. Output Voltage V+=8V, f=1kHz, Inverting Circuit 1 1 0.1 0.1 THD+N [%] THD+N [%] 0.1 Output Voltage [Vrms] 0.01 0.01 Ta=-40,25,85oC o Ta=25,85 C o Ta=-40 C 0.001 0.01 0.001 0.1 1 Output Voltage [Vrms] –8– 10 0.01 0.1 1 Output Voltage [Vrms] 10 NJM2794 ! TYPICAL CHARACTERISTICS THD+N vs. Output Voltage V+=9V, Ta=25oC, Inverting Circuit 1 1 0.1 0.1 THD+N [%] THD+N [%] THD+N vs. Output Voltage V+=9V, Ta=25oC, Non-Inverting Circuit f=100Hz, 10kHz 0.01 f=1kHz 0.001 0.01 0.1 1 f=100Hz, 1kHz,10kHz 0.01 0.001 10 0.01 0.1 Output Voltage [Vrms] 1 1 0.1 0.1 Ta=-40,25,85oC 0.001 Ta=-40,25,85oC 0.01 0.001 10 100 1000 10000 100000 10 100 Frequency [Hz] 1000 10000 100000 Frequency [Hz] Maximum Output Voltage vs. Operating Voltage f=1kHz, THD=0.1%, Non-Inverting Circuit Maximum Output Voltage vs. Operating Voltage f=1kHz, THD=0.1%, Inverting Circuit 4 Maximum Output Voltage [Vrms] 4 Maximum Output Voltage [Vrms] 10 THD+N vs. Output Voltage V+=9V, Vin=1Vrms, BW=22Hz-80kHz, Inverting Circuit THD+N [%] THD+N [%] THD+N vs. Output Voltage V+=9V, Vin=1Vrms, BW=22Hz-80kHz, Non-Inverting Circuit 0.01 1 Output Voltage [Vrms] 3 2 Ta=-40,25,85oC 1 0 3 2 Ta=-40,25,85oC 1 0 0 3 6 9 Operating Voltage [V] 12 15 0 3 6 9 12 15 Operating Voltage [V] –9– NJM2794 ! TYPICAL CHARACTERISTICS Maximum Output Voltage vs. Load Resistance V+=9V, f=1kHz, Ta=25oC, BW=400 - 30kHz THD=0.1% 5 10 8 6 4 V+=13V 3 9V 2 4 Voltage Gain [dB] Maximum Output Voltage [Vrms] Voltage Gain vs. Frequency V+=9V, Vin=1Vrms, Ta=25oC 2 0 -2 Non-Inverting Circuit, Inverting Circuit -4 -6 1 -8 4.3V -10 0 0.1 1 10 10 100 100 Load Resistance [kΩ] Reference Voltage Turn-on behaviour V+=9V, Ta=25℃ Supply Voltage Rejection Ratio [dB] Reference Voltage [V] 100000 0 Cref=4.7µF 4 3.5 3 Cref=22µF 2.5 2 Cref=10µF 1.5 1 0.5 -10 -20 -30 -40 Cref=4.7µF -50 Cref=10µF -60 -70 Cref=22µF -80 -90 -100 0 0 1 2 3 4 5 6 7 8 9 10 10 100 1000 10000 100000 Frequency [Hz] time [sec] Supply Voltage Rejection Ratio vs. Signal Source Resistance Supply Voltage Rejection Ratio vs. Operating Voltage V+=9V, Vrippple=100mV, f=100Hz, Ta=25oC Vripple=100mV, f=100Hz, Rg=600Ω, Ta=25oC 0 0 -10 -10 Supply Voltage Rejection Ratio [dB] Supply Voltage Rejection Ratio [dB] 10000 Supply Voltage Rejection Ratio vs. Frequency V+=9V, Vripple=100mV, Rg=600Ω, Ta=25℃ 4.5 -20 -30 -40 -50 -60 -70 -80 -90 -100 -20 -30 -40 -50 -60 -70 -80 -90 -100 0.1 1 10 Signal Source Resistance [kΩ] – 10 – 1000 Frequency [Hz] 100 0 3 6 9 Operating Voltage [V] 12 15 NJM2794 ! TYPICAL CHARACTERISTICS Common Mode Rejection Ratio vs. Input Voltage V+=9V, f=1kHz, Ta=25oC, BW=400 - 30kHz 0 0 -10 -10 Common Mode Rejection Ratio [dB] Common Mode Rejection Ratio [dB] Common Mode Rejection Ratio vs. Frequency V+=9V, Vin=1Vrms -20 -30 -40 -50 25oC -60 Ta=-40oC -70 -80 o Ta=85 C -90 -100 -20 -30 -40 -50 Ta=-40oC -60 25oC -70 -80 85oC -90 -100 10 100 1000 Frequency [Hz] 10000 100000 0.001 0.01 0.1 1 10 Input Voltage [Vrms] [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. – 11 –