RPM7240-V4R Rohm Semiconductor, RPM7240-V4R Datasheet - Page 20
![RECEIVER REMOTE CTRL 40.0KHZ L](/photos/40/15/401559/rsip-a3_v4_sml.jpg)
RPM7240-V4R
Manufacturer Part Number
RPM7240-V4R
Description
RECEIVER REMOTE CTRL 40.0KHZ L
Manufacturer
Rohm Semiconductor
Specifications of RPM7240-V4R
Sensing Distance
15m
B.p.f. Center Frequency
40.0kHz
Voltage - Supply
2.7 V ~ 3.6 V
Current - Supply
500µA
Orientation
Side View
Mounting Type
Through Hole
Lead Free Status / Rohs Status
Lead free / RoHS Compliant
• Various Types of Optical Noise
• Countermeasures of Set for Optical Noise
Rapid Fluorescent Lamp
The light emission frequency of a standard fluorescent lamp is 100Hz or 120Hz in most of the
countries. It depends on the goverment policy. Although the light emission frequency is
sufficiently lower than the subcarrier frequency of the remote control, the harmonics may cause
a malfunction (i.e., a reduction in the effective distance may result).
High Frequency Modulation Type Fluorescent Lamp
In order to reduce the flickering of light, the light emission frequency of an inverter fluorescent
lamp is modified. The frequency is around 45kHz, which is close to the subcarrier of the remote
controller and becomes noise that cannot be eliminated with ease.
With the incidence of inverter fluorescent light, the effective distance will be shorter in
comparison with the case of the rapid fluorescent lamp.
Incandescent Lamp and Sunlight
These light sources have DC noise but including a large quantity of infrared components used
for the remote control. The incidence of the noise results in a reduction in effective distance.
Lighting apparatus becomes an optical noise source. In many cases, this noise source is
radiated from the upper side. Therefore, at the time of designing the window of the set, limit
the incidence of light from the upper side.
100
80
60
40
20
0
0.2
Fig. 20 Optical Noise Wavelength Characteristics
Sunlight
Fluorescent Lamp
0.5
Wavelength: λ (mm)
18
Incandescent Lamp
Precautions for Designing Receiver Side