NJU72014 ? 1 ? ver.1.9e 2vrms ground referenced stereo line amplifier with lpf q general description the NJU72014 is an audio line amplifier . it can swing 2vrms (5.6v peak-to-peak) signal at 3.3v operating voltage. ground-referenced outputs eliminat e output coupling capacitor. the pop noise suppression circuit removes a pop noise at the power-on and power-off. it is suitable for audio line interface of audio equipment which does not have over 9v regulator. q applications o audio applications requiring 2vrms outputs q features o operating voltage +2.7 to +3.6v o operating current i dd =4.5ma typ.at v + =3.3v, r l =47k ? , no signal o output coupling capacitor-less o pop noise suppression circuit o 2nd order lpf o c-mos technology o package outline msop10 (tvsp10) q block diagram q pin configuration inl inr outl v + gnd cp cm v - outr bias charge pump pop noise suppression mute q package outline NJU72014rb2 110 6 5 no. symbol function 1 inl lch input 2 outl lch output 3 v+ v+ power supply 4 cp flying capacitor positive terminal 5 cn flying capacitor negative terminal 6 v- v- power supply 7 mute mute / pop noise suppression 8 gnd ground 9 outr rch output 10 inr rch input
NJU72014 ? 2 ? q absolute maximum rating (ta=25 c) parameter symbol rating unit supply voltage v + +4 v power dissipation p d 530 (note1)) mw maximum input voltage v imax -v + -0.3 ~ v + +0.3 v operating temperature range topr -40 ~ +85 c storage temperature range tstg -40 ~ +125 c (note1) eia/jedec standard test board (76. 2x114.3x1.6mm, 2layer, fr-4) mounting q recommended operating conditions (ta=25 c unless otherwise specified ) parameter symbol test condition min. typ. max. unit operating voltage v + 2.7 3.3 3.6 v q electrical characteristics (ta=25 c, v + =3.3v, f=1khz, vin=0.6vrms, mute=off, r l =47k ? unless otherwise specified ) parameter symbol test condition min. typ. max. unit operating current i dd no signal - 4.5 10 ma output gain g v 10 10.5 11 db output gain error ? g v -0.5 0 0.5 db maximum output voltage level v omax thd=1% - 2.3 - vrms mute level v mute rg=0 ? , mute=on - -110 - db equivalent input noise voltage v no rg=0 ? , bw:400hz-22khz - -106 - db total harmonic distortion thd bw:400hz-22khz - 0.003 - % channel separation cs rg=600 ? 80 - - db cut-off frequency f c 2 nd order lpf 100 150 200 khz output offset voltage v os rg=0 ? - 1 5 mv power supply rejection ratio psrr vripple=1khz / 100mvrms - 50 - db output impedance r out - 300 - ? q control characteristics (ta=25 c, v + =3.3v, r l =47k ? unless otherwise specified ) parameter symbol test condition min. typ. max. unit mute terminal high muteh mute=off 0.8v + - v + v mute terminal low mutel mute=on 0 - 0.2v + v
NJU72014 ? 3 ? ? test circuit ? i dd ? g v , v omax , thd ? v mute ? v no [v no =(measurement)-gv1] ? cs ? f c mu te- tr mute - tr 1uf v + 1uf char ge pu mp 2 bias inl outl v+ cp cn inr outr gnd mute 1uf 10uf 3 4 5 1 9 8 7 6 10 v- po p no is e suppression a v + mu te- tr mut e- tr 1uf 1uf char ge pu mp 2 bias inl outl v+ cp cn inr outr gnd mute 1uf 10uf 3 4 5 1 9 8 7 6 10 v- po p no is e suppression v + v 10uf v + v 47k ? 47k ? mu te- tr mut e- tr 1uf 1uf char ge pu mp 2 bias inl outl v+ cp cn inr outr gnd mute 1uf 10uf 3 4 5 1 9 8 7 6 10 v- po p no is e suppression v 10uf v + v 47k ? 47k ? mut e- tr mut e- tr 1uf 1uf char ge pu mp 2 bias inl outl v+ cp cn inr outr gnd mute 1uf 10uf 3 4 5 1 9 8 7 6 10 v- po p no is e suppression v + v 10uf v + v 47k ? mu te- tr mut e- tr 1uf 1uf char ge pu mp 2 bias inl outl v+ cp cn inr outr gnd mute 1uf 10uf 3 4 5 1 9 8 7 6 10 v- po p no is e suppression v + v 10uf v + 47k ? 47k ? rg=620 ? 1k ? 820pf 1k ? 820pf mu te- tr mut e- tr 1uf 1uf char ge pu mp 2 bias inl outl v+ cp cn inr outr gnd mute 1uf 10uf 3 4 5 1 9 8 7 6 10 v- po p no is e suppression v + v 10uf v + v 47k ? 47k ?
NJU72014 ? 4 ? ? application note the NJU72014 is an audio line amplifier that eliminates the need for external dc-blocking output capacitors. the NJU72014 has built-in pop suppression circuitry to eliminate disturbing pop noise during power-on, power-off and mute-control. 1. operating principle the NJU72014 has the built-in non-inverted input operational amplifiers, voltage inverter, and pop noise suppression circuitry (fig.1). the voltage inverter for NJU72014 eliminates the need for external dc-blocking output capacitors. the pop suppression circuitry for NJU72014 eliminates the pop noise during power-on, power-off and mute-control. *1) connect a zener diode between v- terminal[6pin] and gnd te rminal[8pin] to prevent connec ting v- terminal[6pin] and v+ terminal[3pin]. fig.1 the NJU72014 functional block diagram mut e- tr mut e- tr 1uf 10uf v + 1uf 1k ? 820pf charge pu mp 2 bias inl outl v + cp cn inr outr gnd mute 1uf 1k ? 820pf 10uf 3 4 5 1 9 8 7 6 10 v - pop noise suppression c2 c3 r1 r3 c9 c8 c11 c6 c4 *1)
NJU72014 ? 5 ? 1.1 external parts 1.1.1 input coupling capacitors c i (c2, c8) the input coupling capacitor (c i ) and the total of the external resistance (r1, r3) and the input resistance (r in =218k ? typ.) for the non-inverted terminal form a high-pass filter with the corner frequency determined in [fc=1/(2 x (r1+218k ?) x c i )). it is necessary to adjust 1uf or more. 1.1.2 flying capacitor (c4) use capacitors with a low-esr (ex. ceramic capaci tors) for optimum performance. design to provide low impedance for the wiring between cp terminal (4pin), cn terminal (5pin), and the flying capacitor (c4). fig.2 the NJU72014 block diagram (4pin, 5pin) 1.1.3 hold capacitor (c6) use capacitors with a low-esr (ex. ceramic capaci tors) for optimum performance. design to provide low impedance for the wiring between the hold capaci tor (c6), v- terminal (6pin) and the gnd on the pcb. separate the gnd pattern connecting to the hold ca pacitor (c6) from that connecting to the gnd terminal (8pin), thus suppressing the influence of switching noise by removing the common impedance of the gnd wiring. design no short-circuits of v- terminal (6pin) and v+ terminal (3pin) on the pcb pattern. fig.3 the NJU72014 block diagram (6pin, 8pin) cp(4pin) cn(5pin) c4=1uf c6 v-(6pin) gnd(8pin)
NJU72014 ? 6 ? 1.1.4 to reducing output signal level output gain level(gv) is adjustable by the value of the r1 and r2 connected to input pin (pin 1,10). add att to input pin of NJU72014 as shown in fig.4. ( ) () 4 3 4 4 3 2 1 4 3 2 log 20 // // log 20 25 . 11 r r r r r r r r r r gv + + + + + + = (1) r4= 200k r3=18k r1=1k c1 r2 in nju72012 out fig.4 NJU72014 with att. ex) in the case of r1=1k ? and r2=82k ? ( ) () () () ] [ 36 . 10 200 18 200 log 20 200 18 // 82 1 200 18 // 82 log 20 25 . 11 log 20 // // log 20 25 . 11 4 3 4 4 3 2 1 4 3 2 db k k k k k k k k k k r r r r r r r r r r gv = + + + + + + = + + + + + + = 1.2 control of v+ terminal and mute terminal 1.2.2 power-on procedure turn on the v+ in the condition of mute terminal is ?low?. after 100msec from power on, change the control voltage of mute terminal (vcnt) from "low" to "high". * it is necessary to stabilize an ic for 100msec. 1.2.3 power-off procedure change the control voltage of mute terminal (vcnt) from "high" to "low".by the mute function, the output signals are stopped from output terminal. turn off the v+. fig.5 power-on / power-off timing chart NJU72014 r1 100msec 100msec t t v+ (3pin) mute (7pin) mute off mute on mute on
NJU72014 ? 7 ? ? terminal description terminal symbol function equivalent circuit voltage 1 10 inl inr ac input 0v 2 9 outl outr ac output 0v 3 v+ supply voltage v+ 4 cp flying capacitor positive terminal - 100 ? v - v + 14.8k ? 5.5k ? 100 ? 100 ? v - v + v + 18k ? 30pf 200k ? v+ v- gnd
NJU72014 ? 8 ? ? terminal description terminal symbol function equivalent circuit voltage 5 cn flying capacitor negative terminal - 6 v- v- voltage -[v+] 7 mute mute/pop noise suppression 0v v - v - v + 100 ? v - v + 400k ? gnd
NJU72014 ? 9 ? idd vs supply voltage no signal 0.0 2.5 5.0 7.5 2.5 3.0 3.5 4.0 supply voltage [v] idd [ma] ta=-40 ? ta=+85 ? ta=+25 ? maximum output voltage vs supply voltage thd+n=1%, rl=47kohm, i/o=inl-outl 1.0 1.5 2.0 2.5 3.0 2.5 3.0 3.5 4.0 supply voltage [v] maximum output voltage [vrms] ta=-40, +25, +85 ? maximum output voltage vs frequency v+=3.3v, thd+n=1%, rl=47kohm, i/o=inl-outl 1.0 1.5 2.0 2.5 3.0 10 100 1000 10000 100000 frequency [hz] maximum output voltage [vrms ] ta=-40, +25, +85 ? output voltage vs road resistance v+=3.3v, vin=0.7vrms, f=1khz, i/o=inl-outl 1.0 1.5 2.0 2.5 3.0 1000 10000 100000 road resistance [ ? ] output voltage [vrms] ta=-40, +25, +85 ? output gain vs frequency (2nd lpf) v+=3.3v, vin=0.6vrms, rl=47kohm, 2nd lpf 0 2 4 6 8 10 12 10 100 1000 10000 10000 0 10000 00 frequency [hz] output gain [db] ta=-40, +25, +85 ? 100000 1000000 thd+n vs output voltage v+=3.3v, f=1khz, bw: 400-22khz(f=1khz), i/o=inl-outl, 0.0001 0.001 0.01 0.1 1 10 100 0.01 0.1 1 10 output voltage [vrms] thd+n [%] ta=-40, +25, +85 ? ? typical characteristics
NJU72014 ? 10 ? thd+n vs frequency v+=3.3v, vin=0.6vrms, rl=47kohm, bw=10-80khz, i/o:inl-outl 0.001 0.01 0.1 1 10 100 1000 10000 100000 frequency [hz] thd+n [%] ta=+25 ? ta=-40 ? ta=+85 ? channel separation vs frequency v+=3.3v, rl=47kohm, vin=0.6vrms, bw:10-80khz, i/o: inr-outl 0 20 40 60 80 100 10 100 1000 10000 100000 frequency [hz] channel separation [db ] ta=-40, +25, +85 ? psrr vs frequency v+=3.3v, vripple=100mvrms, f=1khz, bw: bandpass 0 10 20 30 40 50 60 70 10 100 1000 10000 100000 frequency [hz] psrr [db] ta=-40, +25 ? ta=+85 ? output gain vs mute control voltage v+=3.3v, vin=0.6vrms, f=1khz, bw: 400-22khz -120 -100 -80 -60 -40 -20 0 20 01234 mute control voltage [v] output gain [db] ta=+25 ? ta=-40 ? ta=+85 ? ? typical characteristics [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.
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