SP3490EN-L-TR Datasheet, PDF (7/12 Pages) Exar Corporation – +3.3V Low Power Full-Duplex RS-485 Transceivers with 10Mbps Data Rate

D
Vcc
V_OD
R
R
V_OC
Figure 1. Driver DC Test Load Circuit
Test Circuits
VDM
S1
D
GENERATOR
(NOTE 1)
50Ω
VCC
R L = 27Ω
OUT
C L = 15pF
(NOTE 2)
VOM =
VOH + VOL
2
≈ 1.5V
Figure 2. Driver Propagation Delay Test Circuit
C_L
D
GENERATOR
(NOTE 1)
50Ω
VCC
R_L = _OUT
60Ω
C L= 15pF (NOTE 2)
Figure 3. Driver Differential Output Delay and
Transition Time Circuit.
S1
0V OR 3V
D
GENERATOR
(NOTE 1)
50Ω
C L = 50pF
(NOTE 2)
VCC
R L = 110Ω
OUT
Figure 5. Driver Enable and Disable Timing Circuit,
Output Low
1.5V
S3
-1.5V
VID R
GENERATOR
(NOTE 1)
50Ω
1k
CL= 15pF
(NOTE 2)
S1
VCC
S2
GENERATOR
(NOTE 1)
S1
D
50Ω
CL = 50pF
(NOTE 2)
OUT
RL = 110Ω
VOM =
VOH + VOL
2
≈ 1.5V
Figure 4. Driver Enable and Disable Timing Circuit,
Output High
GENERATOR
(NOTE 1)
V ID
R
50Ω
OUT
CL = 15pF
(NOTE 2)
1.5V
0V
VOM = VCC
2
Figure 6. Receiver Propagation Delay Test Circuit
DE = 0 or Vcc
A/Y
DI = 0 or Vcc
D
B/Z
IOS D
100Ω
-7V to +12V V
Figure 7. Receiver Enable and Disable Timing
Circuit
Figure 8. Driver Short Circuit Current Limit Test
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 510-668-7017 • www.exar.com

SP3490_3491_102_102710