preamplifier + power amplifier for 3v headphone stereos overview the LA4581MB is an auto reverse-supported preamplifier + power amplifier ic that is intended for use in 3v headphone stereos. features . preamplifier muting and preamplifier output on/off can be implemented with one pin. this ic can easily be used to construct a set with a radio. . the power amplifier needs no input/output coupling capacitor. . a high-frequency cut capacitor is connected to the preamplifier input pin and the power amplifier input pin. (anti-buzz provision) . because v ref amp (r 0 =10 w ) is built in, the virtual grounding impedance is about 10 w . this eliminates the need for a large capacitor. . 8 w speaker drivable. package dimensions unit : mm 3112-mfp24s [LA4581MB] sanyo : mfp24s specifications maximum ratings atta=25 c parameter symbol conditions ratings unit maximum supply voltage v cc max 4.5 v allowable power dissipation pd max 530 mw operating temperature topr 20 to +75 c storage temperature tstg 40 to +125 c operating conditions atta=25 c parameter symbol conditions ratings unit recommended supply voltage v cc 3.0 v operating supply voltage range v cc op 1.8 to 3.6 v ordering number: en3535a monolithic linear ic LA4581MB any and all sanyo products described or contained herein do not have specifications that can handle applications that require extremely high levels of reliability, such as life-support systems, aircraft? control systems, or other applications whose failure can be reasonably expected to result in serious physical and/or material damage. consult with your sanyo representative nearest you before using any sanyo products described or contained herein in such applications. sanyo assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all sanyo products described or contained herein. sanyo electric co.,ltd. semiconductor bussiness headquarters tokyo office tokyo bldg., 1-10, 1 chome, ueno, taito-ku, tokyo, 110-8534 japan 22896ha(ii) no.3535-1/10
operating characteristics atta=25 c, v cc =3.0v,f=1 khz, 0.775 v = 0 dbm, r l =10k w (preamplifier), r l =16 w (power amplifier) parameter symbol output min typ max unit [pre + power] quiescent current i cco rg = 2.2 k w (preamplifer) v in = 0 v 17 27 ma voltage gain (closed) vg t v o = 5 dbm 65 68 71 db [preamplifier] voltage gain (open) vgo v o = 5 dbm 70 80 db voltage gain (closed) vg1 v o = 5 dbm 40 db maximum output voltage v o max thd=1%,v cc = 1.8 v 0.1 0.2 v total harmonic distortion thd1 v o = 0.2 v, vg = 40 db/nab 0.05 0.5 % equivalent input noise voltage v n 1 rg = 2.2 k w , b.p.f = 20 to 20 khz 1.3 2.0 v crosstalk ct1 rg = 2.2 k w , tune 1 khz 60 80 db ripple rejection ratio r r 1 rg = 2.2 k w ,v cc = 1.8 v, vr = 20 dbm, f = 100 hz 40 50 db [power amplifer] output voltage p o thd = 10% 23 32 mw voltage gain (closed) vg2 v o = 5 dbm 25 28 31 db total harmonic distortion thd2 p o = 1 mw 0.4 1.0 % interchannel crosstalk ct t v o = 5 dbm, r v =0 w 30 40 db output noise voltage v no rg = 0, b.p.f = 20 to 20 khz 24 40 v ripple rejection ratio r r 2 rg=0,v r = 20 db, f = 100 hz, v cc = 1.8 v 45 60 db input resistance r in 22 30 38 k w dc offset voltage v odc off between 13-14 and 15 90 +90 mv note) power amplifier voltage gain vg2 increases by about 1 db for min/max respectively than specified above when r l =32 w . LA4581MB no.3535-2/10
block diagram test circuit unit (resistance: w , capacitance: f) 1.8 to 3.0 v LA4581MB no.3535-3/10
sample application circuit pin and external part functions (when the voltage is v cc = 3.0 v) pin no. pin function 1 pre gnd 2 pre in1r 1.8 v v turns on when pin 17 is grounded. v a bias resistor (2.2 k w ) must be connected between pin 2 and pin 24 (v ref ) when no head is in use. 3 pre in1f 1.8 v v turns on when pin 17 is floating. v a bias resistor (2.2 k w ) must be connected between pin 3 and pin 24 (v ref ) when no head is in use. 4 pre nf1 1.8 v 5 pre out1 1.8 v v like pin 6, 10 k w load drivable. 6 sw out1 1.8v v provides pre amp1 output when pin 8 is floating (pre mute off)(equivalent to pin 5). v disconnects from pre amp1 and sets r in ^ 500 k w when pin 8 is at v cc (pre mute on). 7 power in1 1.8v v input resistance r in 7 30 k w continued on next page. allowable power dissipation, pd max mw ambient temperature, ta c preamplifier input is applied to pins 2,23/ pins 3,22 when sw on/off, respectively. power mute on when connected to gnd. note) pre closed loop gain vg = 40 db/1 khz nab pre mute on when connected to v cc unit (resistance: w , capacitance: f) 1.8 to 3.6 v LA4581MB no.3535-4/10
continued from preceding page. pin no. pin function 8 pre mute v when v cc is applied, pre mute on. v mute on conditions: v 8in ^ v cc 0.2 v, inflow current i 7 7 60 a (when v cc =3v) 9 ripple filter ref 2.7 v(c 7 = 2.2 f to 33 f) v ripple filter, v ref reference v the v ref ripple rejection ratio worsens when c 7 is made smaller. v r r is 55 db for 22 f; 35 db for 2.2 f. 10 ripple filter out 2.7 v v ripple rejection ratio: r r is 38 db when c 7 = 22 f; 30 db when c 7 = 2.2 f. v outflow current i 7 max=1ma 11 v cc 3.0 v 12 power gnd 13 common 1.2 v 14 power out1 1.2 v v ch1 output. 15 power out2 1.2 v v ch2 output 16 power mute 0.7 v (c 10 = 1.0 f to 4.7 f) v when connected to gnd: power mute on. v mute on conditions: v 16 % 0.3 v, outflow current i 16 7 2.5 a. v c 10 can be used to control mute time. v when c 10 = 2.2 f, v cc =3.0 v 0.7 sec. 17 fwd/rev sw (c11 % 0.47 f) v when connected to gnd, pre in1r (pin 2) and in2r (pin 23) turn on. v when floating, pre in1f (pin 3) and in2f (pin 22) turn on. v c 11 and r 7 are intended for smoothing at the time of switching. v rev condition: v 17 % 0.2 v. 18 power in2 1.8 v v input resistance r in 7 30 k w 19 sw out2 1.8 v v provides pre amp2 when pin 8 is floating (pre mute off) (equivalent to pin 20). v disconnects from pre amp2 and r in ^ 500 k w when pin 8 is v cc (pre mute on). 20 pre out2 1.8 v v like pin 19, 10 k w load drivable. 21 pre nf2 1.8v 22 pre in2f 1.8 v v turns on when pin 17 is floating. v a bias resistor (2.2 k w ) must be connected between pin 22 and pin 24 (v ref ) when no head is in use. 23 pre in2r 1.8 v v turns on when pin 17 is connected to gnd. v a bias resistor (2.2 k w ) must be connected between pin 23 and pin 24(v ref ) when no head is in use. 24 v ref 1.8 v v the reference voltage is set to 3/5 v cc . because vref amp (r o 7 10 w ) is built in, c 17 can be made smaller (1 f). v inflow/outflow current i 24 = 500 a available. sample application: radio set application. as shown above, radio on and pre mute can be implemented with one-circuit switch. LA4581MB no.3535-5/10
ic usage notes 1. the power amplifier outputs and the common amplifier output are connected through resistors of about 60 w . the resistors are for common amplifier oscillation blocking. 2. the preamplifier muting function isolates the preamplifier outputs from sw out. the preamplifier is on even when the preamplifier muting is on. 3. if transient noise is noticeable when the power supply is turned off, add the external circuit described below. transient noise when the power is turned off can be improved by rapidly applying the power amplifier muting. 4. internal equivalent circuit for each sw pin. . pre-mute . power mute . f/r sw w w however, the standby current i st flows even when the power switch is off i st =(v cc v be )/600 k w when v cc = 3.0 v i st = (3.0 0.6)/600 k w 7 4a unit (resistance: w , capacitance: f) mute on condition : v 8in ^ v cc 0.2 v inflow current : i 8 7 60 a (when v cc = 3.0 v) unit (resistance: w ) mute on condition : v 16 % 0.3 v outflow current : i 16 7 2.5 a unit (resistance: w , capacitance: f) rev condition : v 17 % 0.2 v unit (resistance: w , capacitance: f) LA4581MB no.3535-6/10
pre + power quiescent current, icco ma supply voltage, v cc v voltage gain, vg db preamp frequency ,fhz unit (resistance: w , capacitance: f) preamp preamp voltage gain, vgo db supply voltage, v cc v total harmonic distortion, thd % output voltage, v o v preamp [interchannel] preamp maximum output voltage, v o maxv the base correction turns off, causing output dc to increase, and output is obtained. supply voltage, v cc v crosstalk, ct db 79 db at tune 1 khz frequency ,fhz [between f/r] frequency ,fhz 89 db at tune 1 khz preamp preamp equivalent crosstalk, ct db output noise voltage, v no f equivalent ch1, ch2 equivalent supply voltage, v cc v LA4581MB no.3535-7/10
amp output voltage, v o dbm frequency ,fhz drops because of 1 f at 5 kh or more when impedance is small. reference voltage, vref v amp virtual grounding inflow current i s i = 500 a max. output current, i o ma unit (resistance: w , capacitance: f) dc voltage, v dc v supply voltage, v cc v power amp dc voltage, v dc v (vitrual grounding) supply voltage, v cc v maximum output voltage, v o v power amp when both channels output simultaneously power amp voltage gain, vg db when both channels output simultaneously frequency ,fhz supply voltage, v cc v power amp power amp voltage gain, vg db supply voltage, v cc v crosstalk, ct db equivalent frequency ,fhz when both channels output LA4581MB no.3535-8/10
power amp power amp total harmonic distortion,thd % total harmonic distortion, thd % when both channels output simultaneously when both channels output simultaneously supply voltage, v cc v output voltage, p o mw power amp power amp total harmonic distortion, thd % output noise voltage, v no v when both channels output simultaneously output power, p o mw supply voltage, v cc v svrr db power amp preamp supply voltage, v cc v supply voltage, v cc v ch1 and ch2 out are equivalent svrr db LA4581MB no.3535-9/10
LA4581MB ps no.3535-10/10 specifications of any and all sanyo products described or contained herein stipulate the performance, characteristics, and functions of the described products in the independent state, and are not guarantees of the performance, characteristics, and functions of the described products as mounted in the customer? products or equipment. to verify symptoms and states that cannot be evaluated in an independent device, the customer should always evaluate and test devices mounted in the customer? products or equipment. sanyo electric co., ltd. strives to supply high-quality high-reliability products. however, any and all semiconductor products fail with some probability. it is possible that these probabilistic failures could give rise to accidents or events that could endanger human lives, that could give rise to smoke or fire, or that could cause damage to other property. when designing equipment, adopt safety measures so that these kinds of accidents or events cannot occur. such measures include but are not limited to protective circuits and error prevention circuits for safe design, redundant design, and structural design. in the event that any or all sanyo products(including technical data,services) described or contained herein are controlled under any of applicable local export control laws and regulations, such products must not be exported without obtaining the export license from the authorities concerned in accordance with the above law. no part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, or any information storage or retrieval system, or otherwise, without the prior written permission of sanyo electric co. , ltd. any and all information described or contained herein are subject to change without notice due to product/technology improvement, etc. when designing equipment, refer to the ?elivery specification for the sanyo product that you intend to use. information (including circuit diagrams and circuit parameters) herein is for example only ; it is not guaranteed for volume production. sanyo believes information herein is accurate and reliable, but no guarantees are made or implied regarding its use or any infringements of intellectual property rights or other rights of third parties. this catalog provides information as of february, 1996. specifications and information herein are subject to change without notice.
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