Electrical Specifications
5.16 UART Timing
Table 5−37 to Table 5−38 assume testing over recommended operating conditions (see Figure 5−35).
Table 5−37. UART Timing Requirements
MIN
MAX
UNIT
ns
†
†
t
t
Pulse width, receive data bit
Pulse width, receive start bit
0.99U
1.01U
w(UDB)R
†
†
0.99U
1.01U
ns
w(USB)R
†
U = UART baud time = 1/programmed baud rate
Table 5−38. UART Switching Characteristics
PARAMETER
Maximum programmable baud rate
Pulse width, transmit data bit
MIN
MAX
UNIT
MHz
ns
f
t
t
5
baud
†
†
U − 2
U + 2
w(UDB)X
w(USB)X
†
†
Pulse width, transmit start bit
U − 2
U + 2
ns
†
U = UART baud time = 1/programmed baud rate
t
w(USB)X
Data Bits
Start
Bit
TX
t
w(UDB)X
Data Bits
Start
Bit
RX
t
w(UDB)R
t
w(USB)R
Figure 5−35. UART Timings
107
November 2001 − Revised April 2004
SPRS007D
TI [ TEXAS INSTRUMENTS ]
