低功耗,限摆率限制
RS - 485 / RS -422收发器
MAX481/MAX483/MAX485/MAX487–MAX491/MAX1487
100pF
Z
TTL IN
t
R
, t
F
& LT ;为6ns
D
Y
R = 54Ω
A
B
R
接收器
OUT
100pF
图14.接收器传输延迟测试电路
A
500mV/div
V
CC
= 5V
T
A
= +25°C
B
500mV/div
V
CC
= 5V
T
A
= +25°C
B
RO
A
2V/div
2V/div
RO
20ns/div
20ns/div
图15. MAX481 / MAX485 / MAX490 / MAX491 / MAX1487
接收机吨
PHL
图16. MAX481 / MAX485 / MAX490 / MAX491 / MAX1487
接收机吨
PLH
A
500mV/div
V
CC
= 5V
T
A
= +25°C
B
500mV/div
V
CC
= 5V
T
A
= +25°C
B
RO
2V/div
A
2V/div
RO
400ns/div
400ns/div
图17. MAX483 , MAX487 , MAX489接收吨
PHL
图18. MAX483 , MAX487 , MAX489接收吨
PLH
12
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