82092 Datasheet, PDF (5/7 Pages) Vishay Siliconix – IR Receiver Modules for Remote Control Systems

TSOP22..WE1
Vishay Semiconductors
Suitable Data Format
The circuit of the TSOP22..WE1 is designed in that
way that unexpected output pulses due to noise or
disturbance signals are avoided. A bandpass filter, an
integrator stage and an automatic gain control are
used to suppress such disturbances.
The distinguishing mark between data signal and dis-
turbance signal are carrier frequency, burst length
and duty cycle.
The data signal should fulfill the following conditions:
• Carrier frequency should be close to center fre-
quency of the bandpass (e.g. 38 kHz).
• 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 necessary.
• For each burst which is longer than 1.8 ms a corre-
sponding 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
TSOP22..WE1 it can still receive the data signal.
However the sensitivity is reduced to that level that no
unexpected pulses will occur.
Some examples for such disturbance signals which
are suppressed by the TSOP22..WE1 are:
• DC light (e.g. from tungsten bulb or sunlight)
• Continuous signal at 38 kHz or at any other fre-
quency
• Signals from fluorescent lamps with electronic bal-
last with high or low modulation ( see Figure 13 or Fig-
ure 14 ).
IR Signal from fluorescent
lamp with low modulation
0
16920
5
10
15
20
Time ( ms )
Figure 13. IR Signal from Fluorescent Lamp with low Modulation
IR Signal from fluorescent
lamp with high modulation
0
16921
5
10
15
20
Time ( ms )
Figure 14. IR Signal from Fluorescent Lamp with high Modulation
Document Number 82092
Rev. 1.6, 31-Jan-05
www.vishay.com
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