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| 1/16 www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. class-ab s p eak er amplifiers 1.9w+1.9w s t ereo s p eaker amplifier BD7836EFV desc ri ptio n BD7836EFV is a class-ab stereo speaker amplifier, developed fo r note-book pc, desktop pc, portable devices and others. class-ab amplifier has no emi noise. power package htssop-b20 can realize high output power. low circuit current at active mode reduce consumption of batte ry. shutdown current is 0.1a typically, and pop noise level when shutdown turns on and off is very small. this device is suitable for the application that often changes mode between shutdown state and active state. f e atu r es 1) high power 1.9w typ. (vdd=5v, r l =4 ? , thd+n=1%, stereo input) high power 1.2w typ. (vdd=5v, r l =8 ? , thd+n=1%, stereo input) 2) gain selectable by the external control (6,10,15.6,21.6db) 3) pop noise suppression circuitry 4) shutdown function (also mute function) [i sd =0.1a(typ.)] 5) protection circuitry (thermal shutdown, under voltage lockout) 6) power package with thermal pad htssop-b20 a p p lic ati o n s note-book pc, desktop pc, etc. a b s o lute maximum r a tings ( t a=+25 ) parameter symbol ratings unit power supply voltage vddmax 7.0 v power dissipation pd 1 *1 w 3.2 *2 w storage temperature tstg -55 +150 input terminal input voltage range *3 vin -0.3 vdd+0.3 v control terminal input voltage range *4 vctl -0.3 vdd+0.3 v *1 70mm70mm1.6mm fr4 1-layer glass epoxy board(copper on top layer 0%) derating in done at 8mw/ for operating above ta=25 . there are thermal via on the board. *2 70mm70mm1.6mm fr4 4-layer glass epoxy board (copper on bottom 2 and 3 layer 100%) derating in done at 25.6mw/ for operating above ta=25 . there are thermal via on the board. *3 input terminal (lin +, lin-, rin+, rin-) *4 control terminal ( shutdown , gain0, gain1) o per ati ng c o n d i tio n s parameter symbol range unit power supply voltage vdd +4.5 +5.5 v temperature topr -40 +85 * these products arent designed for protection against radioactive rays. no.10077eat07 downloaded from: http:///
technical note 2/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. e l ectr ic c hara cter i stic (unless otherwise specified, ta=+25 , vdd=+5.0v, r l =8 , ac stereo input) parameter symbol limits unit condition min. typ. max. circuit current (active) i cc D 5 10 ma ic active, no load shutdown =hi circuit current (shutdown) i sd D 0.1 2.0 a ic shutdown shutdown =lo technical note 3/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. lot no. (unit : mm) bd7836 p a ck ag e o u tli n es fig.1 htssop-b20 b l oc k di a g ram p i n assi g n me nt t a bl e pin no. terminal name function 1 gnd ground 2 gain0 bit 0 of gain select 3 gain1 bit 1 of gain select 4 lout+ left channel positive output 5 lin- left channel negative differential input 6 pvdd supply voltage terminal 7 rin+ right channel negative differential input 8 lout- left channel negative output 9 lin+ left channel positive differential input 10 bypass tap to voltage divider for internal midsupply bias generator 11 gnd ground 12 nc no connection 13 gnd ground 14 rout- right channel negative output 15 pvdd supply voltage terminal 16 vdd supply voltage terminal 17 rin- right channel negative differential input 18 rout+ right channel positive output 19 shutdown places ic in shutdown mode when held low 20 gnd ground power management depop circuitry gain control rin- rin+ rout+ rout- gain0 gain1 pvdd vdd bypass gnd shutdown lin+ lin- lout- lout+ fig.2 downloaded from: http:/// technical note 4/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. m eas ur ement c i rc uit d i a g ram fig.3 gain control power management + - + - rout+ 18 rout- 14 rin- rin+ gain0 gain1 lin- lin+ right line input signal c rin - 0.47 17 c rin + 0.47 7 23 5 98 4 19 10 16 6.15 vdd bypass shut- down gnd to system control c sr 0.47 c byp 0.1 0.1 c sr 1,11, 13,20 lout+ lout- left line input signal c lin - c lin + 0.47 0.47 v dd v dd pvdd rl rl downloaded from: http:/// technical note 5/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. ap pl ic atio n circ uit e x am pl e fig.4 single ended inputs fig.5 differential inputs gain control power management + - + - rout+ 18 rout- 14 rin- rin+ gain0 gain1 lin- lin+ right line input signal c rin - 0.47 17 c rin + 0.47 7 23 5 98 4 19 10 16 6.15 vdd bypass shut- down gnd to system control c sr 0.47 c byp 0.1 0.1 c sr 1,11, 13,20 lout+ lout- left line input signal c lin - c lin+ 0.47 0.47 v dd v dd pvdd gain control power management + - + - rout+ 18 rout- 14 rin- rin+ gain0 gain1 lin- lin+ right line input signal c rin- 0.47 17 c rin+ 0.47 7 23 5 98 4 19 10 16 6.15 vdd bypass shut- down gnd to system control c sr 0.47 c byp 0.1 0.1 c sr 1,11, 13,20 lout+ lout- left line input signal c lin- c lin+ 0.47 0.47 v dd v dd pvdd downloaded from: http:/// technical note 6/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. ev al u a tio n bo ar d circ uit di ag ram fig .6 ev al u a tio n bo ar d p a rtt s list number part name type, value smd size manufacturer/ part number 4 clin+/-,crin+/- capacitor, 0.47 f 1608 murata grm188r71c474ka01d 2 csr capacitor, 0.1 f 1608 murata grm188r71c104ka01d 1 cbyp capacitor, 0.47 f 1608 murata grm188r71c474ka01d 1 u1 ic, BD7836EFV, class-ab stereo speaker amplifier pkg:htssop-b20 rohm BD7836EFV-e2 1 pcb1 printed-circuit board BD7836EFV D D please connect to gnd . please connect to po w e r sup p l y (vdd=+4.5 5.5v) line. please connect ito inp u t signal line. please connect sp eaker . please connect sp eaker . use these solde r jump er fo r conn ecting th e cont rol te rminal to gn d . use these solde r jump er fo r conn ecting th e cont rol te rminal t o vdd . a aa ? ? y ? y ? ? ? ? downloaded from: http:/// technical note 7/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. desc ri ptio n of e x ter n al p a rt s input coupling capacitors ci (clin+/-,crin+/-) it sets cutoff frequency fc by the follow ing formula by input coupling capacitors ci(clin+/-,crin+/-) and input impedance zi. it makes an input coupling capacitors of evaluation board 0.47 f on evaluation board.. input impedance zi and cutoff frequency fc in each gain settings are given in table1. table1. the relations in the gain settings and cutoff frequency fc. gain0 gain1 gain [db] ri ? ] zi [ ? ] fc [hz] lo lo 6 90k 45k 7.5 lo hi 12 70k 35k 9.7 hi lo 18 45k 22.5k 15 hi hi 24 25k 12.5k 27 the power decoupling capacitors (c sr ) it makes a power decoupling capacitors 0.1 f. because power decoupling capacitors influences total harmonic distortion (thd) and some audio characteristics, please place a good lo w equivalent-series-resistance (esr) capacitors as close as possible to ic. bypass capacitor (c byp ) because bypass capacitor influences thd, psrr and some audio characteristics, please place good low equivalent-series-resistance (esr) capacitor as close as possible to ic. the value of bypass capacitor determines the turn on time and turn off time. refer to the following section of turn on and turn off. it makes bypass capacitor of evaluation board 0.47 f. control terminal each control terminal ( shutdown , gain0, gain1) dont have pull-down resistance internal circuit. connect to gnd line or vdd line or input low or high level voltage to terminals in order to avoid the terminals made high impedance. using ic under the control terminal let hi gh impedance, operation fault may occur. [hz] ci iz 2 1 fc ? ? ? downloaded from: http:/// technical note 8/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. ev al u a tio n bo ar d pcb la y e r fig.7 top layer fig.8 bottom layer downloaded from: http:/// technical note 9/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. t u r n o n an d t u r n of f this ic has the circuit that reduces pop noise at turn on and turn off. reducing pop noise is realized in controlling to adjust the turn on and turn off time. (a)turn on (b)turn off fig. 9 the following table show the turn on time and turn off time when it makes the bypass capacitor 0.47uf. cbyp turn on turn off 0.47uf 280ms 340ms turn on time is defined as the time until byp ass terminal voltage reaches the 90% of vdd/2 after shutdown l h. turn off time is defined as the time until byp ass terminal voltage reaches the 10% of vdd/2 after shutdown h l. the values of above table are typical characteristics. these values will shift by 30% at some conditions. i n put terminal this ic can be inputed signal by differntial inputs or single ended inputs. when sing the single ended inputs, connect the terminal of not signal inputed line to ac gnd with input couppling capacitors. please makes the value of all input capacito rs same because of preventing pop noise. if they are not same value, for example, lout+=0.47f, lo ut-=0.33f, it caused pop noise increase and characteristics become worse. shutdown 5v/div. bypass 1v/div. lout- 1v/div. turn on time turn off time downloaded from: http:/// technical note 10/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. a b o u t th e the rma l d e si gn by t h e ic characteristics of an ic have a great deal to do with the temperature at which it is used, and exceeding absolute maximum ratings may degrade and destroy elements. careful consider ation must be given to the heat of the ic from the two standpoints of immediate damage and long-term reliability of oper ation. pay attention to points such as the following. since an maximum junction temperature (tj max .)or operating temperature range (topr) is shown in the absolute maximum ratings of the ic, to reference the va lue, find it using the pd-ta charac teristic (temperature derating curve). if an input signal is too great when there is insufficient radiation, tsd (therma l shutdown) may operate. tsd, which operates at a chip temperature of approximately +180 , is canceled when this goes below approximately +100 . since tsd operates persistently with the purpose of preventing chip damage, be aware that long-term use in the vicinity that tsd affects decrease ic reliability. temperature derating curve fig.10 power dissipation vs. ambient temperature power dissipation values vary according to the board on which the ic is mounted. the power dissipation of this ic when mounted on a multilayer board designed to radiate is greater than the val ues in the graph above. note) values are actual measurements and are not guaranteed. reference data htssop-b20 2.5 2.0 1.0 0.5 0.0 0 25 50 75 100 125 150 ambient temperature ta( ) power dissipation pd(w) 1w measurement conditions: ic unit rohm standard board mounted board 70mm 70mm 1.6mmt board fr4 1-layer glass epoxy board (copper on top layer 0%) board fr4 2-layer glass epoxy board (copper on top layer 0%) board fr4 3-layer glass epoxy board (copper on top layer 100%) board fr4 4-layer glass epoxy board (copper on top layer 100%) 85 1.5 2.3 2.3w 3.5 3.2 3.2w 1.45w downloaded from: http:/// technical note 11/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. t y pic a l character i stics table of graphs items parameter figure number total harmonic distortion plus noise (thd+n) vs. frequency 11, 12, 17, 18 vs. output power 13, 14, 15, 16, 19, 20, 21, 22 supply current (icc) vs. supply voltage 23 shutdown current (isd) vs. supply voltage 24 gain vs. frequency 25 crosstalk vs. frequency 26 supply ripple rejection ratio vs. frequency 27 shutdown attenuation vs. frequency 28 power dissipation vs. output power 29 efficiency vs. output power 30 output power vs. load resistance 31 downloaded from: http:/// technical note 12/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. = = = [] [%] = = = = = = = [] [%] = = = = = = = [] [%] = = = = = = [] [%] = = = [] [%] = = = [] [%] = = = = = [] [%] = = = = = = = [] [%] = = = fig.11 fig.12 fig.13 fig.14 fig.15 fig.16 fig.17 fig.18 downloaded from: http:/// technical note 13/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. = = = = [] [%] = = = = = = = [] [%] = = = = = = [] [%] = = = = = = [] [%] = = = a a [] [] a a [] [] a = = [] a [] a = = = [] a [] fig.19 fig.20 fig.21 fig.22 fig.23 fig.24 fig.25 fig.26 downloaded from: http:/// technical note 14/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. = y= = aa [] [] aa = = = [] aa [] a = = = [] a [] = = = = = = [] [%] = = = a a = = = a a[] [%] = = fig.27 fig.28 fig.29 fig.30 fig.31 downloaded from: http:/// technical note 15/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. n o te s fo r use (1) absolute maximum ratings this ic may be damaged if the absolute maximum ratings fo r the applied voltage, tem perature range, or other parameters are exceeded. therefore, avoid usin g a voltage or temperature that ex ceeds the absolute maximum ratings. if it is possible that absolute maximum ratings will be ex ceeded, use fuses or other physical safety measures and determine ways to avoid exceeding the ics absolute maximum ratings. (2) gnd terminals potential try to set the minimum voltage for gnd terminal s potential, regardless of the operation mode. (3) shorting between pins and mounting errors when mounting the ic chip on a board, be very careful to set the chips orientation and position precisely. when the power is turned on, the ic may be damaged if it is not mounted correctly. the ic may also be damaged if a short occurs (due to a fo reign object, etc.) between two pins, between a pin and the power supply, or between a pin and the gnd. (4) operation in strong magnetic fields note with caution that operation faults may occur when this ic operates in a strong magnetic field. (5) thermal design ensure sufficient margins to the thermal design by taking in to account the allowable power dissipation during actual use modes, because this ic is power amp. when excessive signal in puts which the heat dissipation is insufficient condition, it is possible that thermal shutdown circuit is active (6) thermal shutdown circuit this product is provided with a built-in thermal shutdown circuit. when the the rmal shutdown circuit operates, the output transistors are placed under open status. the thermal shutdown circuit is primarily intended to shutdown the ic avoiding thermal runaway under abnormal conditions wi th a chip temperature exceeding tjmax = +150 , and is not intended to protect and secure an electrical appliance (7) load of the output terminal this ic corresponds to dynamic speaker load, and doesn't correspond to the load except for dynamic speakers. (8) the short protection of the output terminal this ic has short protection circuit. the function protects the ic from rash current on road. (9) operating ranges the rated operating power supply voltage range (vdd=+4.5v +5.5v) and the rated operating temperature range (ta=-40 +85 ) are the range by which basic circuit functions is operated. characteristics and rated output power are not guaranteed in all power supply voltage ranges or temperature ranges. (10) electrical characteristics electrical characteristics show the typical performance of device and depend on board layout, parts, power supply. the standard value is in mounting device and parts on surface of rohms board directly. (11) maximum output power when stereo inputs at r l =4 , maximum output power may not achieve up to typical value because the device heats. ensure sufficient margins to the thermal design to get larger output power. downloaded from: http:/// technical note 16/16 BD7836EFV www.rohm.com 2010.07 - rev . a ? 2010 rohm co., ltd. all rights reserved. or der in g p a rt n u mb er b d 7 8 3 6 e f v - e 2 part no. part no. 7836 package efv:htssop-b20 packaging and forming specification e2: embossed tape ad reel (unit : mm) htssop-b20 s 0.08 s 11 20 11 0 (max 6.85 include burr) 6.5 0.1 (2.4) 4.4 0.1 0.325 6.4 0.2 (4.0) 0.17 +0.05 - 0.03 1.0 0.2 0.5 0.15 0.65 0.08 0.05 0.85 0.05 1.0max 0.24 +0.05 - 0.04 ? order quantity needs to be multiple of the minimum quantity. datasheet d a t a s h e e t notice - ge rev.002 ? 2014 rohm co., ltd. all rights reserved. notice precaution on using rohm products 1. our products are designed and manufac tured for application in ordinary elec tronic equipments (such as av equipment, oa equipment, telecommunication equipment, home electroni c appliances, amusement equipment, etc.). if you intend to use our products in devices requiring ex tremely high reliability (such as medical equipment (note 1) , transport equipment, traffic equipment, aircraft/spacecra ft, nuclear power controllers, fuel c ontrollers, car equipment including car accessories, safety devices, etc.) and whose malfunction or failure may cause loss of human life, bodily injury or serious damage to property (specific applications), please consult with the rohm sale s representative in advance. unless otherwise agreed in writing by rohm in advance, rohm shall not be in any way responsible or liable for any damages, expenses or losses incurred by you or third parties arising from the use of any ro hms products for specific applications. (note1) medical equipment classification of the specific applications japan usa eu china class class class b class class class 2. rohm designs and manufactures its products subject to strict quality control system. however, semiconductor products can fail or malfunction at a certain rate. please be sure to implement, at your own responsibilities, adequate safety measures including but not limited to fail-safe desi gn against the physical injury, damage to any property, which a failure or malfunction of our products may cause. the following are examples of safety measures: [a] installation of protection circuits or other protective devices to improve system safety [b] installation of redundant circuits to reduce the impact of single or multiple circuit failure 3. our products are designed and manufactured for use under standard conditions and not under any special or extraordinary environments or conditio ns, as exemplified below. accordin gly, rohm shall not be in any way responsible or liable for any damages, expenses or losses arising from the use of an y rohms products under any special or extraordinary environments or conditions. if you intend to use our products under any special or extraordinary environments or conditions (as exemplified below), your independent verification and confirmation of product performance, reliability, etc, prior to use, must be necessary: [a] use of our products in any types of liquid, incl uding water, oils, chemicals, and organic solvents [b] use of our products outdoors or in places where the products are exposed to direct sunlight or dust [c] use of our products in places where the products ar e exposed to sea wind or corrosive gases, including cl 2 , h 2 s, nh 3 , so 2 , and no 2 [d] use of our products in places where the products are exposed to static electricity or electromagnetic waves [e] use of our products in proximity to heat-producing components, plastic cords, or other flammable items [f] sealing or coating our products with resin or other coating materials [g] use of our products without cleaning residue of flux (ev en if you use no-clean type fluxes, cleaning residue of flux is recommended); or washing our products by using water or water-soluble cleaning agents for cleaning residue after soldering [h] use of the products in places subject to dew condensation 4. the products are not subjec t to radiation-proof design. 5. please verify and confirm characteristics of the final or mounted products in using the products. 6. in particular, if a transient load (a large amount of load applied in a short per iod of time, such as pulse. is applied, confirmation of performance characteristics after on-boar d mounting is strongly recomm ended. avoid applying power exceeding normal rated power; exceeding the power rating under steady-state loading c ondition may negatively affect product performance and reliability. 7. de-rate power dissipation (pd) depending on ambient temper ature (ta). when used in seal ed area, confirm the actual ambient temperature. 8. confirm that operation temperat ure is within the specified range described in the product specification. 9. rohm shall not be in any way responsible or liable for fa ilure induced under deviant condi tion from what is defined in this document. precaution for mounting / circuit board design 1. when a highly active halogenous (chlori ne, bromine, etc.) flux is used, the resi due of flux may negatively affect product performance and reliability. 2. in principle, the reflow soldering method must be used; if flow soldering met hod is preferred, please consult with the rohm representative in advance. for details, please refer to rohm mounting specification downloaded from: http:/// datasheet d a t a s h e e t notice - ge rev.002 ? 2014 rohm co., ltd. all rights reserved. precautions regarding application examples and external circuits 1. if change is made to the constant of an external circuit, pl ease allow a sufficient margin considering variations of the characteristics of the products and external components, including transient characteri stics, as well as static characteristics. 2. you agree that application notes, re ference designs, and associated data and in formation contained in this document are presented only as guidance for products use. theref ore, in case you use such information, you are solely responsible for it and you must exercise your own independent verification and judgment in the use of such information contained in this document. rohm shall not be in any way responsible or liable for any damages, expenses or losses incurred by you or third parties arising from the use of such information. precaution for electrostatic this product is electrostatic sensitive product, which may be damaged due to electrostatic discharge. please take proper caution in your manufacturing process and storage so that voltage exceeding t he products maximum rating will not be applied to products. please take special care under dry condit ion (e.g. grounding of human body / equipment / solder iron, isolation from charged objects, se tting of ionizer, friction prevention and temperature / humidity control). precaution for storage / transportation 1. product performance and soldered connections may deteriora te if the products are stor ed in the places where: [a] the products are exposed to sea winds or corros ive gases, including cl2, h2s, nh3, so2, and no2 [b] the temperature or humidity exceeds those recommended by rohm [c] the products are exposed to di rect sunshine or condensation [d] the products are exposed to high electrostatic 2. even under rohm recommended storage c ondition, solderability of products out of recommended storage time period may be degraded. it is strongly recommended to confirm sol derability before using products of which storage time is exceeding the recommended storage time period. 3. store / transport cartons in the co rrect direction, which is indicated on a carton with a symbol. otherwise bent leads may occur due to excessive stress applied when dropping of a carton. 4. use products within the specified time after opening a humidity barrier bag. baking is required before using products of which storage time is exceeding the recommended storage time period. precaution for product label qr code printed on rohm products label is for rohms internal use only. precaution for disposition when disposing products please dispose them proper ly using an authorized industry waste company. precaution for foreign exchange and foreign trade act since our products might fall under cont rolled goods prescribed by the applicable foreign exchange and foreign trade act, please consult with rohm representative in case of export. precaution regarding intellectual property rights 1. all information and data including but not limited to application example contained in this document is for reference only. rohm does not warrant that foregoi ng information or data will not infringe any intellectual property rights or any other rights of any third party regarding such information or data. rohm shall not be in any way responsible or liable for infringement of any intellectual property rights or ot her damages arising from use of such information or data.: 2. no license, expressly or implied, is granted hereby under any intellectual property rights or other rights of rohm or any third parties with respect to the information contained in this document. other precaution 1. this document may not be reprinted or reproduced, in whol e or in part, without prior written consent of rohm. 2. the products may not be disassembled, converted, modified, reproduced or otherwise changed without prior written consent of rohm. 3. in no event shall you use in any wa y whatsoever the products and the related technical information contained in the products or this document for any military purposes, incl uding but not limited to, the development of mass-destruction weapons. 4. the proper names of companies or products described in this document are trademarks or registered trademarks of rohm, its affiliated companies or third parties. downloaded from: http:/// datasheet datasheet notice C we rev.001 ? 2014 rohm co., ltd. all rights reserved. general precaution 1. before you use our pro ducts, you are requested to care fully read this document and fully understand its contents. rohm shall n ot be in an y way responsible or liabl e for fa ilure, malfunction or acci dent arising from the use of a ny rohms products against warning, caution or note contained in this document. 2. all information contained in this docume nt is current as of the issuing date and subj ec t to change without any prior notice. before purchasing or using rohms products, please confirm the la test information with a rohm sale s representative. 3. the information contained in this doc ument is provi ded on an as is basis and rohm does not warrant that all information contained in this document is accurate an d/or error-free. rohm shall not be in an y way responsible or liable for an y damages, expenses or losses incurred b y you or third parties resulting from inaccur acy or errors of or concerning such information. downloaded from: http:/// |
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