1/4 rev. l structure : silicon monolithic integrated circuit product : band-pass filter for sp ectrum analyzer for car audio systems type : ba3834f function : 1. built-in band pa ss filter for spectrum analyzer. ba3834f is for 7 bands 2. designed for 5v micr ocomputer power voltage 3. sop18 package requiri ng few external parts absolute maximum ratings (ta=25) parameter symbol rating unit power supply voltage vcc 7 v power dissipation pd 450 mw operating temperature topr -25+75 storage temperature tstg -55+125 this value decreases 4.5 mw/ for ta=25 or more. operating voltage rangeta25 parameter symbol min. typ. max. unit power supply voltage vcc 4.5 5.0 6.5 v electrical characteristics unless specified particularly, ta25v cc 5vr l 10m,v ain -30dbvsel1 parameter symbol limit unit conditions min. typ. max. circuit current i c c D 10 15 ma v ain =0v, a, b, c, sel=0 maximum output level v om 4.0 4.8 D v v ain =-14dbv, measured at each output output offset voltage v os D 30 150 mv v ain =0v, sel=0/1, measured at each output (cycle time : t s =50ms) standard output level 1 v 01 0.65 1.35 1.70 v f in =68hz. a=0. b=0. c=1. standard output level 2 v 02 0.65 1.35 1.70 v f in =170hz. a=0. b=1. c=0. standard output level 3 v 03 0.65 1.35 1.70 v f in =420hz. a=0. b=1. c=1. standard output level 4 v 04 0.65 1.35 1.70 v f in =1khz. a=1. b=0. c=0. standard output level 5 v 05 0.65 1.35 1.70 v f in =2.4khz. a=1. b=0. c=1. standard output level 6 v 06 0.65 1.35 1.70 v f in =5.9khz. a=1. b=1. c=0. standard output level 7 v 07 0.65 1.35 1.70 v f in =14.4khz. a=1.b=1.c=1. application example note that rohm cannot provide adequate confirmation of patents. the product described in this specification is designed to be u sed with ordinary electronic equipment or devices (such as audi o-visual equipment, office-automation equipment, communications devices, electrical appliances, and electronic toys). should you intend to use this pro duct with equipment or devices which require an extremely high level of reliability and the m alfunction of which would directly endanger human life (such as medical instruments , transportation equipment, aerospace machinery, nuclear-reacto r controllers, fuel controllers and other safety devices), please be sure to consul t with our sales representative in advance.
2/4 rev. l parameter symbol limit unit conditions min. typ. max. input impedance r in 80 100 120 k f in =1khz. common-mode rejection ratio cmrr 25 50 D db f in =1khz. v ain =v cin . logic input high level v ih 2.5 5.0 D v logic input low level v il D 0 0.5 v not applicable in t he when item 10 of the operation notes applies. output response time t D 5 10 sec discharge level dl D 3 D db reset pulse width t r =10s (typ.) *1 the time from the rise of a, b, c or sel until the rise of a out (90 of peak). if the output selection time is less than th is, the output voltage is not guaranteed and the reset pulse is not generated. *2 automatically generated internally based on the output selec t signal. for the duration that this signal is h, a resister is connected to the peak hold capacitor, and the output level drops by C3db (typ.) for o ne pulse. *3 the of the bandpas filter is 3.5 for f 01 to f 06 , and 2.5 for f 07. not designed for radiation resistance. output select logic table : don't care. timing chart sel a b c aout 0 gnd 1 0 0 0 gnd 1 0 0 1 68hz 1 0 1 0 170hz 1 0 1 1 420hz 1 1 0 0 1khz 1 1 0 1 2.4khz 1 1 1 0 5.9khz 1 1 1 1 14.4khz
3/4 rev. l block diagram application example (1) numbers and data in entries are r epresentative design values an d are not guaranteed values of the items. (2) although we are confident in recommending the sample appli cation circuits, carefully check their characteristics further when using them. when modifying externally attached co mponent constants before use, determine them so that they have sufficient margins by taking into account var iations in externally attached components and the rohm lsi, not only for static characteristics but also includin g transient characteristics. (3) absolute maximum ratings if applied voltage, operating temperature range, or other absol ute maximum ratings are exceeded, the lsi may be damaged. do not apply voltages or temperatures that exceed the absolute maximum ratings. if you think of a case in which absolute maximum ratings are exceeded, enforce fu ses or other physical safety measures and investigate how not to apply the conditions under which absolut e maximum ratings are exceeded to the lsi. (4) gnd potential make the gnd pin voltage such that it is the lowest voltage eve n when operating below it. actually confirm that the voltage of each pin does not become a lower voltage than th e gnd pin, including transient phenomena. terminal number terminal name 1 biasc 2 vrefc 3 rref 4 n.c 5 difout 6 n.c 7 cin 8 ain 9 vcc 10 a 11 b 12 c 13 n.c 14 sel 15 n.c 16 test 17 aout 18 gnd outline dimension ba 383 4 f lot no. terminal number/ terminal name b p f 1 7 0 h z b p f 6 8 h z b p f 4 2 0 h z b p f 1 k h z b p f 2 . 4 k h z b p f 5 . 9 k h z b p f 1 4 . 4 k h z h o l d p e a k h o l d p e a k h o l d p e a k h o l d p e a k hold p e a k h o l d p e a k h o l d p e a k r e s r e s r e s r e s r e s r e s r e s d i f a - c c a m p x d e c r e f f e r e n c e c u r r e n t b i a c v r e f c r r e f n . c . d i f o u t n . c . c i n a i n v c c g n d a o u t t e s t n . c . s e l n . c . c b a peak s biasc sop18 (unitmm)
4/4 rev. l (5) thermal design perform thermal design in which there are adequate margins by t aking into account the allowable power dissipation in actual states of use. (6) shorts between pins and misinstallation when mounting the lsi on a board, pay adequate attention to ori entation and placement discrepancies of the lsi. if it is misinstalled and the power is turned on, the lsi may be dama ged. it also may be damaged if it is shorted by a foreign substance coming between pins of the lsi or between a p in and a power supply or a pin and a gnd. (7) operation in stro ng magnetic fields adequately evaluate use in a strong magnetic field, since there is a possibility of malfunction. (8) frequency characteristics the frequency characteristics of this ic are determined by the resistor connected between the r ref terminal and gnd. for the specification conditions, the value of this resistor is 100k if it is necessary to set the frequency characteristics accurately, use a variable resistor (note: all bands will shift together). (9) load characteristics to convert the bias sense output signal to the gnd sense signal, the ic performs a v / i conversion, and then an i /v conversion using a 10kresistor (typ.) for the output. therefore, if the load circuit connected to the aout pin has a mos structure there is no problem (eg. microprocessor input port), but if the connected circuit has a low input impedance, it may cause the output level to drop. (10) external resistor for the control pin when using a common port for the output select control and fl drive, you must add a diode and resistor as shown in the right figure to prevent the fl drive ? l ? voltage from destroying the ic. in this case, the ? l ? voltage applied to the internal comparator input terminal v 1 is given by: to maintain a noise margin of at least 2.5v with respect to the comparator threshold level vref, the representative values for vref, r1 and r2 are 1.5v, 20k, and 10krespectively. this gives: and from this, the following condition is obtained: r30k in this case, the ? l ? level voltage v2 for the ic will be: v 2 0.75v (11) recommended operating ranges provided that the ic is operated within the recommended operating conditions and the recommended temperature range, the basic circuit functions are guaranteed. within these ranges, ratings for electrical characteristics for conditions other than those stipulated cannot be guaranteed, but the inherent function of the band pass f ilter will be maintained. (12) output offset voltage the relationship between the output offset voltage and the output selection cycle (cycle time) for this ic is shown in fig.5. the maximum output offset voltage of 150mv that is given in the electrical characteristics table is under the condition that ts = 200ms. when ts is greater than 50ms, the graph of the output offset voltage is a straight line at 150mv. when ts is below 50ms, due to transient characteristics of the peak hold circuit, the graph is a line sloping downwards to the right. in other words, the shorter the cycle, the larger the output offset voltage. furthermore, the output offset voltage may shift due to soldering or other temperature stresses from the surroundings. therefore, when setting the spectral analyzer light level, take into consideration the points given above and make sure that it does not light by mistake during quiescent periods. use the chart below as a guide for this, and, if necessary, leave even a larger margin. v 1 = v ref r 1 +r 2 +r 1.5v+0.25v 1.5v 20k +20k +r 20k +r ba3834f
r1120 a www.rohm.com ? 2011 rohm co., ltd. all rights reserved. notice rohm customer support system http://www.rohm.com/contact/ thank you for your accessing to rohm product informations. more detail product informations and catalogs are available, please contact us. notes no copying or reproduction of this document, in part or in whole, is permitted without the consent of rohm co.,ltd. the content specied herein is subject to change for improvement without notice. the content specied herein is for the purpose of introducing rohm's products (hereinafter "products"). if you wish to use any such product, please be sure to refer to the specications, which can be obtained from rohm upon request. examples of application circuits, circuit constants and any other information contained herein illustrate the standard usage and operations of the products. the peripheral conditions must be taken into account when designing circuits for mass production. great care was taken in ensuring the accuracy of the information specied in this document. however, should you incur any damage arising from any inaccuracy or misprint of such information, rohm shall bear no responsibility for such damage. the technical information specied herein is intended only to show the typical functions of and examples of application circuits for the produc ts. rohm does not grant you, explicitly or implicitly, any license to use or exercise intellectual property or other rights held by rohm and other parties. rohm shall bear no responsibility whatsoever for any dispute arising from the use of such technical information. the products specied in this document are intended to be used with general-use electronic equipment or devices (such as audio visual equipment, ofce-automation equipment, commu- nication devices, electronic appliances and amusement devices). the products specied in this document are not designed to be radiation tolerant. while rohm always makes efforts to enhance the quality and reliability of its products, a product may fail or malfunction for a variety of reasons. please be sure to implement in your equipment using the products safety measures to guard against the possibility of physical injury, re or any other damage caused in the event of the failure of any product, such as derating, redundancy, re control and fail-safe designs. rohm shall bear no responsibility whatsoever for your use of any product outside of the prescribed scope or not in accordance with the instruction manual. the products are not designed or manufactured to be used with any equipment, device or system which requires an extremely high level of reliability the failure or malfunction of which may result in a direct threat to human life or create a risk of human injury (such as a medical instrument, transportation equipment, aerospace machinery, nuclear-reactor controller, fuel- controller or other safety device). rohm shall bear no responsibility in any way for use of any of the products for the above special purposes. if a product is intended to be used for any such special purpose, please contact a rohm sales representative before purchasing. if you intend to export or ship overseas any product or technology specied herein that may be controlled under the foreign exchange and the foreign trade law, you will be required to obtain a license or permit under the law.
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