TFDU4100 Vishay, TFDU4100 Datasheet - Page 6

• Manufacturer Part Number: TFDU4100
• Manufacturer: Vishay
• Type: TX/RXr

Specifications of TFDU4100

• Peak Wavelength: 900nm
• Angle Of Half Sensitivity: 48°
• Pulse Width: 4us
• Led Supply Voltage: -0.5 to 6V
• Package Type: Ultra Small Profile
• Fall Time: 600/200ns
• Rise Time: 600/1400ns
• Dimensions: 9.7x4.7x4
• Operating Supply Voltage (typ): 2.5/3.3/5V
• Operating Supply Voltage (min): 2/2.7V
• Operating Supply Voltage (max): 5.5V
• Mounting: Surface Mount
• Pin Count: 8
• Operating Temp Range: -25C to 85C
• Operating Temperature Classification: Commercial
• Data Rate: 115.2Kbps
• Lead Free Status / RoHS Status: Compliant

TFDU4100
Vishay Semiconductors
Table 1.
Recommended Application Circuit Components
The sensitivity control (SC) pin allows the minimum
detection irradiance threshold of the transceiver to be
lowered when set to a logic HIGH. Lowering the irra-
diance threshold increases the sensitivity to infrared
signals and increases transmission range up to 3
meters. However, setting the Pin SC to logic HIGH
also makes the transceiver more susceptible to trans-
mission errors due to an increased sensitivity to fluo-
rescent light disturbances. It is recommended to set
the Pin SC to logic LOW or left open if the increased
range is not required or if the system will be operating
in bright ambient light.
Shutdown
The internal switch for the IRED in Vishay Semicon-
ductors SIR transceivers is designed to be operated
like an open collector driver. Thus, the V
can be an unregulated power supply while only a well
regulated power source with a supply current of 1.3
mA connected to V
to the remainder of the transceiver circuitry in receive
mode. The term V
supply pin to indicate that V
independently to shut down the transceiver. It is
allowed to keep the power supply connected to the
IRED Anode. In transmit mode, the current at V
slightly higher (approximately 4 mA average at 3 V
supply current) and the voltage is not required to be
kept as stable as in receive mode. A voltage drop of
V
ing the voltage directly from the Pin V
figure 1). This configuration minimizes the influence
of high current surges from the IRED on the internal
analog control circuitry of the transceiver and the
application circuit. Also board space and cost savings
can be achieved by eliminating the additional linear
regulator normally needed for the IRED’s high current
requirements. The transceiver can be very efficiently
shutdown by keeping the IRED connected to the
power supply V
power source to V
from a microcontroller (see figure 4). In shutdown,
current loss is realized only as leakage current
through the current limiting resistor to the IRED (typi-
www.vishay.com
6
CC1
Component
is acceptable down to about 2.0 V when buffer-
C1
C2
R1
R2
CC2
14 Ω, 0.25 W (recommended using two 7 ΩM, 0.125 W
CC1/SD
CC1/SD
CC1/SD
but switching off V
is used here for the power
is needed to provide power
resistor in series, (V
can be provided directly
CC1
Recommended Value
4.7 µF, Tantalum
0.1 µF, Ceramic
can be switched off
47 Ω, 0.125 W
CC1
CC1/SD
to GND see
CC2
CC2
source
= 5 V)
CC1
. The
is
cally 5 nA). The settling time after switching V
on again is approximately 50 μs. Vishay Semiconduc-
tors’ TOIM4232 interface circuit is designed for this
shutdown feature. The V
the TOIM4232 can be used to power the transceiver
with the necessary supply current. If the microcontrol-
ler or the microprocessor is unable to drive the supply
current required by the transceiver, a low-cost SOT23
pnp transistor can be used to switch voltage on and
off from the regulated power supply (see figure 5).
The additional component cost is minimal and saves
the system designer additional power supply costs.
Supply
Power
Supply
Power
Microcontroller or
Microprocessor
+
–
TFDU4100 (Note: Typical Values Listed)
Receive Mode
at 5 V: I
at 2.7 V: I
Transmit Mode
at 5 V: I
at 2.7 V: I
20 mA
TFDU4100 (Note: Typical Values Listed)
Receive Mode
at 5 V: I
at 2.7 V: I
Transmit Mode
at 5 V: I
at 2.7 V: I
Regulated Power Supply
+
–
Microcontroller or
Regulated Power Supply
Microprocessor
IRED
IRED
IRED
IRED
IRED
IRED
IRED
IRED
20 mA
50 mA
CRCW-1206-7R00-F-RT1
CRCW-1206-47R0-F-RT1
= 210 mA, I
= 210 mA, I
VJ 1206 Y 104 J XXMT
= 210 mA, I
= 210 mA, I
293D 475X9 016B 2T
= 210 mA, I
= 210 mA, I
50 mA
Vishay Part Number
= 210 mA, I
= 210 mA, I
Figure 4.
Figure 5.
CC_SD
S
S
S
S
= 1.3 mA
S
= 5 mA (Avg.)
S
S
S
= 1.3 mA
= 5 mA (Avg.)
= 1.0 mA
= 3.5 mA (Avg.)
, S0 or S1 outputs on
I
S
= 1.0 mA
= 3.5 mA (Avg.)
Document Number 82514
I S
I
IRED
V
V CC1 /SD
R1
Anode
I IRED
IRED
CC1
R1
Anode
IRED
Rev. 1.6, 03-Jul-06
/SD
14878
14879
CC1/SD