TSH511
INFRARED STEREO HEADPHONE APPLICATION
The right side of the figure shows the block-diagram of an infrared stereo receiver using the TSH511. The
sensitive LNA directly connected to the photodiode does not require an external pre-amplifier. After filter-
ing, the amplified signals are limited and demodulated with quadrature demodulators. The two integrated
audio buffers directly drive the stereo headphones. The audio power reaches 2x20mW in two 16Ω loads.
The built-in squelch function fades-out the audio when the incoming infrared signal is low. The standby in-
puts SBY1 and SBY2 enable only one receiver for the mono applications.
IR stereo HiFi transmitter
(Television)
IR stereo HiFi receiver
(Headphones)
Vcc: 2.3 to 5.5V
Current < 15 mA
Right
channel
LNA + ALC
Line inputs
Left
channel
LNA + ALC
TSH512
TX2
VOX
buffer2
SBY
TX1
buffer1
Power supply:
2.3 to 5.5V
Icc < 20 mA stereo
photodiode
Vcc
LNA
LED
Hi2F.i3s&te2re.8o:MHz
carriers
2.3 MHz
filter
RX2
TSH511
Audio
buffer2
20 mW / 16 Ω
RX1
filter
2.8 MHz
Audio
buffer1
20 mW / 16 Ω
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