Document Number: 82094

www.vishay.com

Rev. 2.1, 18-Jul-08

83

New TSOP21..

IR Receiver Modules for

Remote Control Systems

Vishay Semiconductors

SUITABLE DATA FORMAT

The TSOP21.. series is designed to suppress spurious

output pulses due to noise or disturbance signals. Data and

disturbance signals can be distinguished by the devices

according to carrier frequency, burst length and envelope

duty cycle. The data signal should be close to the band-pass

center frequency (e.g. 38 kHz) and fulfill the conditions in the

table below.

When a data signal is applied to the TSOP21.. in the

presence of a disturbance signal, the sensitivity of the

receiver is reduced to insure that no spurious pulses are

present at the output. Some examples of disturbance signals

which are suppressed are:

• DC light (e.g. from tungsten bulb or sunlight)

• Continuous signals at any frequency

• Modulated IR signals from common fluorescent lamps

(example of noise pattern is shown in figure 14)

Fig. 14 - IR Signal from Fluorescent Lamp

with Low Modulation

Note

For data formats with long bursts (10 carrier cycles or longer) we recommend the TSOP22.. because of the better noise suppression.

010

15

20

Time (ms)

16920

IR Signal from Fluorescent

Lamp with Low Modulation

5

TSOP21..

Minimum burst length

6 cycles/burst

After each burst of length

a minimum gap time is required of

6 to 70 cycles

≥ 10 cycles

For bursts greater than

a minimum gap time in the data stream is needed of

70 cycles

> 1.1 x burst length

Maximum number of continuous short bursts/second

2000

Compatible to NEC code

yes

Compatible to RC5/RC6 code

yes

Compatible to RCMM code

yes

Compatible to RECS-80 code

yes

Compatible to r-Step and r-Map data format

yes

Compatible to XMP data format

yes

Suppression of interference from fluorescent lamps

Most common disturbance signals are suppressed