page 1 of 6 1. overview the hc 34018 speakerphone integrated circuit in corporates the necessary amplifiers attenuators and control functions for a high quality hands-free spea kerphone system. incl uded are microphone amplifier, audio power amp for speaker, transmit and receive attenuator, a monitoring system for background noise level and an attenuation control sy stem which responds to the relative transmit and receive level as well as background level. also included are voltage regulator circuits both for internal and external circuit. a chip select pin allows the chip to be powe red down when not in use. the csc34018cp applications include speakerphone for household and business use, intercom system, automotive telephones and others. its features are: all necessary level detection and attenuation control for hands-free telephone in one single chip background level monitoring with long time constant wide dynamic operating range with through signal compression on-chip supply and reference voltage regulation typical 100mw output into 25 load and peak level limiting to reduce distortion chip select pin for active/standby switch linear volume control microphone att noise signal att cont. comparator peak limiter receive transmit level det vcc reg speaker amp det det tx rx receive level att 9 17 15 13 10 12 25 11 2 23 3 4 5 6 8 7 26 27 20 21 18 16 28 1 24 19 22 14 transmit amp voice switched speakerphone circuit for hand free system HC34018 hsin semiconductor pte ltd www.hsin.com.s g
page 2 of 6 2. 2 pin description pin no. symbol description pin no. symbol description 1 con aa att gain control 15 out p power output 2 con ata transmit att gain control 16 v + input dc supply voltage 3 in ta transmit att input 17 agc p power agc control 4 out ta transmit att output 18 en digital chip select input 5 in td transmit level detector input 19 in p power input 6 out td transmit level detector output 20 reg regulation 7 in rd receive level detector input 21 v b bias voltage 8 out rd receive level detector output 22 gnd ground 9 in mc microphone input 23 out cmp comparator output 10 out mc microphone output 24 con vol volume control 11 cmp nv noise level compare 25 fil ac att control filter 12 cmp tv signal level compare 26 iut ra receive att output 13 in cmp comparator input 27 in ra receive att input 14 gnd p power ground 28 con ara receive att gain 3. electrical characteristics 3. 1 absolute maximum ratings unless otherwise specified, t amb = 25 parameter symbol value unit v + terminal voltage v + 12/-1.0 v chip select terminal voltage v en 12/-1.0 v speaker power ground voltage v 14 3.0/-1.0 v volume control terminal voltage v con v cc /-1.0 v operating temperature t amb -20 ~ 70 storage temperature t stg -65 ~ 150 3. 2 recommended operating conditions va l u e parameter symbol recommended conditions min typ max unit v + terminal voltage v + 6.0 11 v chip select terminal voltage v en 0 11 v internal regulation current i cc 0 3.0 ma volume control terminal voltage v con 0.55 v b v receive att input signal voltage v iira 0 250 mv microphone amp input signal voltage v imc 0 5.0 mv speaker power ground voltage v 14 -10 10 mv
page 3 of 6 3.3 electrical characteristics unless otherwise specified, t amb = 25 , add supply voltage on pin 22, v + =7.5v, v en =0.7v. receiving mode: v 8 =5v; transmitting mode: v 6 =5v, v 11 =0v standby mode: v 6 =5v, v 11 =5v va l u e parameter symbol test conditions min typ max unit supply voltage v =11v, v 18 =0.7v 9.0 ma supply current i v+ v =11v, v 18 =1.6v 800 ua v cc voltage v cc v =7.5v 4.9 5.4 5.9 v line regulation v cclin 6.5v v + 11v 65 150 mv output resistance r o(vcc) i cc =3.0ma 6.0 20 dropout voltage v sat v =5.0v 80 300 mv v b voltage v b v =7.5v 2.5 2.9 3.3 v output resistance r o(vb) v b , i b =1.7ma 250 receive attenuators att gain a ra receive, f=1.0khz v 24 =v b , v 27 =250mv 2.0 6.0 10 db range a ra receive to transmit 40 44 48 db idle mode a rai receive, f=1.0khz v 24 =v b v 27 =250mv -20 -16 -12 db receive output voltage v rao receive 1.8 2.3 3.2 v delta out ra v rao receive to transmit 100 mv out ra sink current a raol receive 75 ua out ra source current i raoh receive 1.0 3.0 ma input resistance r raoh receive 3.5 5.0 8.0 k volume control v con receive 0.6v b v 24 v b 24.5 32.5 db transmit attenuators att gain a ta transmit f=1.0khz v 3 =250mv 4.0 6.0 8.0 db range a ta transmit to receive 40 44 48 db idle mode a tai standby f=1.0khz, v 3 =250mv -16.5 -13 -8.5 db transmit output voltage v ota transmit 1.8 2.3 3.2 v delta out ra v rao transmit to receive 100 mv out ra sink current a taol transmit 75 ua out ra source current i taoh transmit 1.0 3.0 ma input resistance r tai 3.5 5.0 8.0 k receive 150 mv transmit 6.0 mv fil ac terminal voltage v acf standby 75 mv power amplifier for speaker gain a p v 19 =20mv 33 34 35 db input resistance r ip 15 22 37 k output voltage v op v 19 with capacitor to gnd 2.4 3.0 3.6 v output high level v poh v 19 =0.1v, v 15 =-100ma 5.5 v output low level v pol v 19 = -0.1v, v 15 =100ma 600 mv
page 4 of 6 va l u e parameter symbol test conditions min typ max unit speaker amplifier amp gain a mc v 9 =10mv, f=1.0khz 32.5 34 35 db input resistance r imc 6.5 10 16 k logamps receive leakage current i lkord v 8 =v b -1.0v 2.0 ua transmit leakage current i lkotd v 6 =v b -1.0v 2.0 ua transmit to receive threshold i th ratio of i tli to i rli at 20 ua 0.8 1.2 transmit detector idle 0 comparator output voltage v ccmp transmit 4.0 v cp2 current source i cp2 5.0 10 13 ua distortion transmit distortion d ra in r to out p v 27 =10mvrms,1khz 1.5 % receive distortion d ta in mc to out ta v 9 =5.0mvrms,1khz 2.0 % 4. test circuit + 1uf + 47uf + 47uf + 1uf + 47uf + 1000uf + 4.7uf + 47uf + 4.7uf 0.1uf 3.3k 2.2m 2.2m 18k 24k 91k 30k 18k 4.3k 25 /1w 200k 100k 47k 0.068uf 0.068uf 1uf sw2 0.1uf 0.1uf 0.01uf 0.047uf + 47uf sw1 9 5 6 7 8 21 24 25 3 2 4 27 28 26 19 14 15 1 17 22 20 16 18 23 11 12 13 10 mc in out in outp v v+ vcc ra ta out b v b mc 4.7k 0.0068uf in
page 5 of 6 5. characteristics curve 10k 100k 1m -70 -60 -50 -40 -30 -20 -10 0 +10 db 10k 100k 1m -70 -60 -50 -40 -30 -20 -10 0 +10 db 0.1 0.5 10 -70 -60 -50 -40 -30 -20 -10 0 +10 db -40 -35 -30 -25 -20 -15 -5 0 +5 db max gain vacf=6.0mv max att rr=30k vacf=150mv vcc=v b rtx max gain vacf=6.0mv max att vacf=150mv rr=30k vcc=v b rrx gtx vs.rtxrr vacf=6.0mv vacf=6.0mv vacf=150mv vacf=150mv atx vs.rtxrr grx vs.rrxrr arx vs.rrxrr 1.0 5.0 ratio rrx=18k rtx=91k rr=30k circuit in receive mode gtx grx min recommanded level 0.2 0.4 0.6 0.8 1.0 vcc/v b rrx=18k rtx=91k rr=30k gtx grx vacf(mv) 150 120 90 60 30 0 10 30 -40 -35 -30 -25 -20 -15 -5 0 +5 db 0 60 100 140 40 20 80 120 160 -20 -40 -60 -80 0 50 100 150 200 rlo.tlo(mv) 250 rli.tli.xdi.(ua) in i (rli.tli.xli) vb (rlo.tlo.cpl) out vo tage r=2700 c=0.1uf r=4700 c=0.068uf (rlo.tlo) 2.2uf 2.2m vb c r rli.tli in i (1.0kh) 50 70 8.0 6.0 4.0 2.0 0 9.0 8.0 7.0 vsko max(vp_p) 11 10 v+(v) 10 6.0 5.0 4.0 25 load no load rli.tli(mvp-p) rlo.tlo.cpi(mv)
page 6 of 6 6. application circuit 7. package dimensions 47uf 0.05uf sw2 2.0k 25 20k 24k + 47uf + 47uf 91k 30k 18k 4.3k 200k 2.2m 2.2m 0.01uf 0.05uf + 47uf + 4.7uf + 4.7uf + 1.0uf 0.1uf 0.068uf 4.7k 3.3k 100k 4.7k 0.068uf 0.068uf 0.1uf + 47uf + 4.7uf + 1.0uf 0.01uf 0.01uf 1m 10k 47k 68k 47k 68k 27k 4.7k 470k 2.2k 0.1uf 33k + 10uf 8.2k 15k 0.068uf b in4007x4 7.5v in4737 1000uf 27 0.001uf 0.05uf 0.001uf 0.0047uf 470k 47k 22k 470k sw1 9 15 14 24 20 2 1 28 26 19 12 23 6 8 21 22 27 7 18 16 17 25 11 5 4 13 10 3 tip ring v vcc v b mic b v b
|
