HSDL-3021-021 Lite-On Electronics, HSDL-3021-021 Datasheet - Page 15

• Manufacturer Part Number: HSDL-3021-021
• Description: Infrared Transceivers IR Transceiver 4.0Mb/s
• Manufacturer: Lite-On Electronics

Specifications of HSDL-3021-021

• Wavelength: 885 nm
• Continual Data Transmission: 4 Mbit/s
• Transmission Distance: 50 cm
• Radiant Intensity: 10 mW/sr
• Half Intensity Angle Degrees: 30 deg to 60 deg
• Pulse Width: 4 us, 1.6 us
• Maximum Rise Time: 40 ns, 600 ns
• Maximum Fall Time: 40 ns, 600 ns
• Led Supply Voltage: 0 V to 6.5 V
• Operating Voltage: 2.4 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 25 C
• Dimensions: 8 mm x 3 mm x 2.5 mm
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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Appendix B: PCB Layout Suggestion
The effects of EMI and power supply noise can poten-
tially reduce the sensitivity of the receiver, resulting in re-
duced link distance. The PCB layout played an important
role to obtain a good PSRR and EM immunity resulting in
good electrical performance. Things to note:
1. The ground plane should be continuous under the
2. The shield trace is a wide, low inductance trace back
3. VLED can be connected to either unfiltered or
4. V
5. IOV
6. Preferably a multi-layered board should be used
part, but should not extend under the shield trace.
to the system ground. CX1, CX2, CX3, CX4 and CX5 are
optional supply filter capacitors; they may be left out
if a clean power supply is used.
unregulated power supply. The bypass capacitors
should be connection before the current limiting
resistor R2 respectively. In a noisy environment,
including capacitor CX3and CX4 can enhance supply
rejection. CX3 that is generally a ceramic capacitor of
low inductance providing a wide frequency response
while CX4 is tantalum capacitor of big volume and fast
frequency response. The use of a tantalum capacitor
is more critical on the VLED line, which carries a high
current.
unregulated power supply. The Resistor, R1 together
with the capacitors, CX1 and CX2 acts as the low pass
filter.
VCC supply. The capacitor, CX5 acts as the bypass
capacitor.
to provide sufficient ground plane. Use the layer
underneath and near the transceiver module as Vcc,
and sandwich that layer between ground connected
board layers. The diagram below demonstrate an
example of a 4 layer board:
CC
pin can be connected to either unfiltered or
CC
is connected to the ASIC voltage supply or the
• Top Layer: Connect the metal shield and module
• Layer 2: Critical ground plane zone. 3 cm in all directions
• Layer 3: Keep data bus away from critical ground plane
• Bottom layer: Ground layer. Ground noise <75 mVp-
ground pin to bottom ground layer; Place the bypass
capacitors within 0.5 cm from the V
of the module.
around the module. Connect to a clean, noiseless
ground node (e.g., bottom layer).
zone.
p. Should be separated from ground used by noisy
sources.
CC
and ground pin