shenzhen luguang electronic technology co.,l td . 1. this specification shall co ver the characteristics of ceramic fil ter with 455khz,inten ed for use in tr ansceivers,etc. 2. part number: LT455HTU 3. electronical specifications a. centre frequency(f ) : 455khz1.0khz b. band width at 6 db : 3.0khzmin.(to 455khz) c. band width at 40 db : 9.0khzmax.(to 455khz) d. stop band attenuation : 35 db min.(at f 100khz) e. ripple : 2.0 db max.( at f 5.0khz) f. insertion loss : 6.0 db max.(at the smallest loss) g temprature coefficient . of center frenquency : 50ppm/ max.(-20 to +80) h. input/output impedance : 2.0k ? note : a) center frequency shall be defied as the central value of the band wtth al 6 db b) temprature coefficient of center frequency shall be defined as the average of the central frequecy. 4. measurement a. environmental condition measurement shall be carried out at the reference temperature of 25 2 . it shall be possibly done at 5 to 35 cunless it is questionable. b. measuring circuit #s.s.g. (standard signal generation) LT455HTU ceramic filter r.f.v.m. (radio frequency voltage meter) rg+r1=r2=2.0k ? c =50pf
shenzhen luguang electronic technology co.,l td . 5. dimensions(mm) 6. environmental characteristics 6-1 high temperature exposure subject the fitter to +80 for 96 hours. then release the filter into the specifications in table 1. 6-2 moisure keep the filter at 40 and 95%rhfor 96 hours.then release the filter into the room conditions for 1 to 2 hours prior to the measuremen t. it shall fulfill the specifications in table 1. 6-3 low temperature exposure subject the filter to -20 for 96 hours. then release the filter into the room conditions for 1 to 2 hours prior to the measurement. it shall fulfill the specific ations in table 1. LT455HTU ceramic filter
shenzhen luguang electronic technology co.,l td . 6-4 temperature cycling subject the filter to alow temperature of -55 for 30 minutes. followsing by a high temperature of +85 for 30 minutes. then release the filter into the room conditions for 1 to 2 hours prior to the mesurement. it shall meet the specifications in table 1. 6-5 resistance to solder heat dip the filter terminals no closer than 1.5mm into the solder bath at 270 10 for 10 1 sec. then release the filter in to the room conditions for 1 to 2 hours. the filter shall meet the specifications in table 1. 6-6 mechanical shock drop the fil ter random ly onto the concrete floor from the height of 30cm 3 ti mes.the filter shall fulfill the specifications in table 1. 6-7 vibration subject the filter to the vibration for 1 hour each in x,y and z axes with the amplitude of 1.5mm at 10 to 55hz. the filter shall fulfillthe specifications in table 1. 6-8 lead fatigue 6-8-1 pulling test weight along with the direction of lead without an shock 3 kg. the filter shall satisfy all the initiall characteristics. 6-8-2 bending test lead shall be subject to withstand against 90 bending in the derection of thickness. this operation shall be done toward both direction.the fil ter shall show noevidence of damage and shall satisfy all the initial electric al characteristics. table 1 item specification centre frequency(f ) 4551.0 khz max band width(6 db) 3.0 khz min selectivity(40 db) 9.0 khz max stop band attenuation 35 db min ripple 2.0 db max insertion loss 6.0 db max LT455HTU ceramic filter
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