HSDL-3021-021 Avago Technologies US Inc., HSDL-3021-021 Datasheet - Page 24

• Manufacturer Part Number: HSDL-3021-021
• Description: Infrared Transceivers FIR + RC
• Manufacturer: Avago Technologies US Inc.

Specifications of HSDL-3021-021

• Wavelength: 885 nm
• Continual Data Transmission: 4 Mbit/s
• Transmission Distance: 50 cm
• Radiant Intensity: 4 mW/sr
• Half Intensity Angle Degrees: 30 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

Two-TxD Direct Transmission Mode
In the two-TxD direct
transmission mode, the LED can
be driven separately for IrDA and
RC mode of operation through the
TxD_IR and TxD_RC pins
respectively. This mode can be
used when the external controller
utilizes separate transmit pins for
IrDA and RC operation modes,
thereby eliminating the need for
external multiplexing.
Please refer to the Transceiver
I/O truth table for more detail.
24
Bandwidth Selection Timing
The power on state should be the
IrDA SIR mode. The data transfer
rate must be set by a program-
ming sequence using the TxD_IR
and SD inputs as described below.
Note: SD should not exceed the
maximum, t
Setting to the High Bandwidth
MIR/FIR Mode (0.576 Mbits/s to
4 Mbits/s)
1. Set SD input to logic “HIGH.”
2. Set TxD_IR input to logic
3. Set SD to logic “LOW” (this
4. After waiting t
Wait t
“HIGH.” Wait t
negative edge latches state of
TxD_IR, which determines
speed setting).
TxD_IR can be set to logic
“LOW.” TxD_IR is now re-
enabled as normal IrDA
transmit input for the High
Bandwidth MIR/FIR mode.
A
C
5 s, to prevent shutdown.
200 ns.
S
H
50 ns.
50 ns
Transceiver Control I/O Truth Table for Two-TxD Direct Transmission Mode
SD
0
0
0
0
1
*The shutdown condition will set the transceiver to the default mode (IrDA-SIR)
Setting to the Low Bandwidth SIR
Mode (2.4 kbits/s to 115.2 kbits/s)
1. Set SD input to logic “HIGH.”
2. Set TxIR input to logic
3. Set SD to logic “LOW” (this
4. TxIR must be held for t
TxIR
“LOW.” Wait t
negative edge latches state of
TxIR, which determines
speed setting).
50 ns. TxIR is now re-enabled
as normal IrDA transmit
input for the Low Bandwidth
SIR mode.
SD
TxIR
0
0
1
1
0
50%
TxRC
0
1
0
1
0
S
t
A
50%
50 ns.
t
C
LED
OFF
ON
ON
-
OFF
S
t
S
Remarks
IR Rx enabled. Idle mode
Remote control operation
IrDA Tx operation
Not recommended (both transmitters off)
Shutdown mode*
50%
t
H
50%
HIGH: MIR/FIR
LOW: SIR