VSOP98260 Datasheet, PDF (1/3 Pages) Vishay Siliconix – VSOP98260 for IR Code Learning Applications

VISHAY SEMICONDUCTORS
www.vishay.com
Infrared Remote Control Receivers
Application Note
VSOP98260 for IR Code Learning Applications
ESD
• To maximize the sensitivity, the TIA input pin has only
HBM class 1B ESD protection! Care should be taken
never to touch or otherwise expose this pin to an adverse
ESD source.
FEATURES
• Supply voltage: 2.0 V to 3.6 V
• Supply current: 0.6 mA to 0.9 mA
• Carrier-out-function: carrier frequency from 20 kHz to
60 kHz and burst length accurately correspond to the
input signal
• Small outline package 2 mm x 2 mm DFN-8 package
• Can be used with either a pvhotodiode or an IR emitter
used as a detector
• AC coupled input is insensitive to DC photocurrents
There is a wide interest in universal remote controls, which can be used to diminish the “clutter” of remote controls typically
present in a modern living room setting. Training the universal remote to send the correct code to each of possibly many
appliances in any media setting is not a simple task. Usually, the manufacturer of the universal remote control owns a database
of literally thousands of brand-model combinations, and the corresponding remote control code base for each model. The
universal remote must know the modulation frequency and pulse patterns represented in the code base in order to correctly
transmit a valid command to the appliance via a key press. Training the universal remote requires the user to identify his
appliances in the data base, and then by some means load the universal remote with the correct code base for each appliance.
While some users may have little difficulty with this set-up routine, others may be challenged. Also, even the largest data bases
inevitably lack some models present in the field, the number of which is mind boggling. There exists therefore a need for
universal remotes to learn their codes directly from the user. Assuming the precondition that the user still possesses the original
remote controls for his appliances, these remotes can be used as a “teacher” for a code learning circuit on the universal remote.
The process is simple. An application program guides the user to position his appliance remote near an infrared sensitive
component on the universal remote, and then asks the user to press a specific key. This causes the appliance remote to transmit
an infrared code, which is received in the universal remote and stored in memory. The universal remote now knows it must also
transmit this exact same code when the corresponding command is requested (e.g. “1”, “2”, … “channel up”, “volume up” etc.).
This process is repeated for each key which must be learned.
Infrared remote controls transmit their signals via an infrared LED. The simplest and least expensive code learning technique
devised to date uses this same infrared LED as both the code transmitter and the code detector for receiving signals from the
appliance remote. IR LEDs are not very efficient detectors. Fortunately, for code learning we want to use an inefficient detector
to eliminate any spurious signals present in the room. The much stronger signal from the appliance remote, which is held close
to the detector, will be enough to capture a clean signal.
Revision: 19-Jul-12
1
Document Number: 82588
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000