TSOP4838 Vishay, TSOP4838 Datasheet - Page 5

• Manufacturer Part Number: TSOP4838
• Description: Infrared Receivers 4.5-5.5V 38kHz
• Manufacturer: Vishay

Specifications of TSOP4838

• Carrier Frequency: 38 KHz
• Supply Current: 0.85 mA
• Beam Angle: 45 deg
• Data Transmission Rate: 800 bits/s
• Mounting Style: Through Hole
• Transmission Distance: 45 m
• Viewing Angle: 45 deg
• Output Current: 5 mA
• Operating Voltage: 2.7 V to 5.5 V
• Power Dissipation: 10 mW
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 25 C
• Transmission Range: 45m
• Directivity: 45°
• Supply Voltage Range: 2.7V To 5.5V
• Opto Case Style: Through Hole
• Operating Temperature Range: -25°C To +85°C
• Svhc: No SVHC
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

Suitable Data Format
The circuit of the TSOP48.. is designed in that way
that unexpected output pulses due to noise or distur-
bance signals are avoided. A bandpass filter, an inte-
grator 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 (repetitive pulse), NEC Code (repetitive data),
Toshiba Micom Format, Sharp Code, RC5 Code,
RC6 Code, R-2000 Code, Sony Code.
When a disturbance signal is applied to the TSOP48..
it can still receive the data signal. However the sensi-
tivity is reduced to that level that no unexpected
pulses will occur.
Some examples for such disturbance signals which
are suppressed by the TSOP48.. 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 ).
Document Number 82090
Rev. 11, 23-Jun-03
VISHAY
Figure 14. IR Signal from Fluorescent Lamp with high Modulation
Figure 13. IR Signal from Fluorescent Lamp with low Modulation
16920
16921
0
0
IR Signal from fluorescent
lamp with high modulation
IR Signal from fluorescent
lamp with low modulation
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5
Time ( ms )
Time ( ms )
10
10
Vishay Semiconductors
15
15
TSOP48..
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20
www.vishay.com
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