VISHAY HS0038B Vishay Telefunken Suitable Data Format Code,RC6 Code,R-2000 Code. henadistubanoesgnali5ap5begiothetSegeae and duty cycle. sensitivity is reduced to that level pulses will occure. The data signal should fullfill the following condition: iegengyoe6apsg他g,8kgeocenle Burst length should be 10 cycles/burst or longer .DClight(e.g.from tungsten bulb or sunlight) r et .Continuous signal at 38kHz or at any other frequency 800 short bursts per second can be received Figure B). 10 20 time [ms] A. rom Fluorescent Lamp with low Modulatio 10 time [s] Figure B:IR Signal from Fluorescent Lamp with high Modulation Rea70geo8ra2o02HS0038B Vishay Telefunken Rev. 7, 05-Dec-00 3 (7) Document Number 82002 www.vishay.com Suitable Data Format The circuit of the HS0038B is designed in that way that unexpected output pulses due to noise or disturbance signals are avoided. A bandpassfilter, an integrator stage and an automatic gain control are used to suppress such disturbances. The distinguishing mark between data signal and disturbance signal are carrier frequency, burst length and duty cycle. The data signal should fullfill the following condition: • Carrier frequency should be close to center frequency of the bandpass (e.g. 38kHz). • Burst length should be 10 cycles/burst or longer. • After each burst which is between 10 cycles and 70 cycles a gap time of at least 14 cycles is neccessary. • For each burst which is longer than 1.8ms a corresponding gap time is necessary at some time in the data stream. This gap time should be at least 4 times longer than the burst. • Up to 800 short bursts per second can be received continuously. Some examples for suitable data format are: NEC Code, Toshiba Micom Format, Sharp Code, RC5 Code, RC6 Code, R–2000 Code. When a disturbance signal is applied to the HS0038B it can still receive the data signal. However the sensitivity is reduced to that level that no unexpected pulses will occure. Some examples for such disturbance signals which are suppressed by the HS0038B are: • DC light (e.g. from tungsten bulb or sunlight) • Continuous signal at 38kHz or at any other frequency • Signals from fluorescent lamps with electronic ballast with high or low modulation (see Figure A or Figure B). 0 5 10 15 20 time [ms] Figure A: IR Signal from Fluorescent Lamp with low Modulation 0 5 10 15 20 time [s] Figure B: IR Signal from Fluorescent Lamp with high Modulation