IBM31T1100 Datasheet, PDF (7/8 Pages) List of Unclassifed Manufacturers – Integrated Infrared Transceiver Module

IBM31T1100A
Programming the Receiver Bandwidth
The IBM31T1100A powers on with the upper limit of the receiver
bandwidth set to 1.2 Mbps operation. To set the bandwidth for
operation at 4 Mbps, apply timings as shown in Figure 14 to the
SD/BW and the TX inputs. Note that the internal LED driver is
disabled when SD/BW is active and is not enabled until the next
rising edge of TX. This ensures that the LED(s) will not be active
during bandwidth adjustment. It is recommended that the SD/BW
pin be connected to GND if bandwidth adjustment and shutdown
mode are not used.
To switch the IBM31T1100A from the default state to 4 Mbps and
vice versa, the programming specifications are as follows:
Setting the receiver to 4 Mbps mode
1. Set the SD/BW input to logic high.
t 2. Set the TX input to logic high. Wait tS 200 ns.
3. Set the SD/BW to logic low. (This high-to-low transition
latches the state of TX, which determines the receiver
bandwidth.)
t 4. After waiting tH 200 ns, set the TX input to logic low. The
receiver is now in high bandwidth mode, the optimal setting
for 4 Mbps operation.
Package Dimensions
5.45 ± 0.5
3.75 ± 0.5
SD/BW
TX
(Setting high bandwidth mode)
TX
(Setting low bandwidth mode)
t_S
50%
50%
t_H
V _IH
V _IL
V_IH
50%
VIL
VIL
Figure 13. Bandwidth Programming
Setting the receiver to 9.6 kbps-to-1.2 Mbps mode
1. Set the SD/BW input to logic high.
t 2. Ensure that the TX input is at logic low. Wait tS 200 ns.
3. Set the SD/BW to logic low. (This high-to-low transition
latches the state of TX, which determines the receiver
bandwidth.)
t 4. Ensure that the TX input remains low for tH 200 ns. The
receiver is now in low bandwidth mode, which is the optimal
setting for data rates from 9.6 kbps to 1.2 Mbps.
13 ± 0.5
A
6.5 ± 0.5
0.5 A
0.6 _{± 0.2}
B
0.275 ± 0.075
2.35 ± 0.3
6.7 ± 0.4
0.5 B
0.9 ± 0.1
0.5 ± 0.1
0.635
(7X) 1.27
(2X) 1.45
Dimensions in mm.
7