SP485R Datasheet, PDF (5/9 Pages) Exar Corporation – 1/10th Unit Load RS-485 Transceiver

SWITCHING WAVEFORMS
+3V
DRIVER INPUT
0V
B
DRIVER
OUTPUT _A
DIFFERENTIAL ^VO⁺
OUTPUT 0V
V_A –V_B ^VO^–
f ≥1MHz; t_R ≤10ns; t_F ≤10ns
1.5V
t _PLH
t _PHL
V_O ^1/2VO
t _DPLH
t _DPHL
t_R
t _SKEW = |t _DPLH - t_DPHL|
Figure 6. Driver Propagation Delays
1.5V
1/2V_O
t_F
+3V
DE
0V
5V
A, B
V_OL
V_OH
A, B
0V
f = 1MHz; t_R < 10ns; t_F < 10ns
1.5V
t _ZL
2.3V
Output normally LOW
2.3V
t _ZH
Output normally HIGH
1.5V
t _LZ
0.5V
0.5V
t _HZ
Figure 7. Driver Enable and Disable Times
V_OD2⁺
A– B
V_OD2^–
f = 1MHz; t_R ≤10ns ; t_F ≤ 10ns
0V
INPUT
V_OH
RECEIVER OUT
V_OL
t_PHL
1.5V
OUTPUT
t_PLH
0V
1.5V
Figure 8. Receiver Propagation Delays
+3V
RE
0V
5V
RECEIVER OUT
V_IL
V_IH
RECEIVER OUT
0V
1.5V _{f = 1MHz; tR ≤ 10ns; tF ≤ 10ns}
t_ZL
1.5V
Output normally LOW
1.5V
t_ZH
Output normally HIGH
1.5V
t_LZ
0.5V
0.5V
t_HZ
Figure 9. Receiver Enable and Disable Times
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com

SP485R_100_072309