DATA
0
1
0
1
0
0
1
1
0
1
1
t2
t1
t2
t1
IRRX
nIRRX
Parameter
min
typ
max
units
t1
t1
t1
t1
t1
t1
t1
t2
t2
t2
t2
t2
t2
t2
Pulse Width at 115kbaud
Pulse Width at 57.6kbaud
Pulse Width at 38.4kbaud
Pulse Width at 19.2kbaud
Pulse Width at 9.6kbaud
Pulse Width at 4.8kbaud
Pulse Width at 2.4kbaud
Bit Time at 115kbaud
Bit Time at 57.6kbaud
Bit Time at 38.4kbaud
Bit Time at 19.2kbaud
Bit Time at 9.6kbaud
1.4
1.4
1.4
1.4
1.4
1.4
1.4
1.6
3.22
4.8
2.71
3.69
µs
µs
µs
µs
µs
µs
µs
µs
µs
µs
µs
µs
µs
µs
5.53
9.7
11.07
22.13
44.27
88.55
19.5
39
78
8.68
17.4
26
52
104
208
416
Bit Time at 4.8kbaud
Bit Time at 2.4kbaud
Notes:
1. Receive Pulse Detection Criteria: A received pulse is considered detected if the
received pulse is a minimum of 1.41µs.
2. IRRX: CRC Bit 0: 1 = RCV active low
nIRRX: CRC Bit 0: 0 = RCV active high (default)
FIGURE 14 - IRDA SIR RECEIVE TIMING
SMSC DS – FDC37N3869
Page 123
Rev. 10/25/2000
SMSC [ SMSC CORPORATION ]
