低功耗，限摆率限制
RS - 485 / RS -422收发器
100pF
Z
TTL IN
t
R
, t
F
＆ LT ;为6ns
D
Y
R = 54
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. HWD481 / HWD485 / HWD490 / HWD491 / HWD487
接收机吨
PHL
图16. HWD481 / HWD485 / HWD490 / HWD491 / HWD1487
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. HWD483 ， HWD487 - HWD489接收机吨
PHL
图18. HWD483 ， HWD487 - HWD489接收机吨
PLH
12
