XRT4500
MULTIPROTOCOL SERIAL NETWORK INTERFACE IC
REV. 1.0.5
áç
ELECTRICAL CHARACTERISTICS (CONTINUED)
SYMBOL PARAMETER
MIN
TYP
MAX
V.28 RECEIVER
Maximum Transmission Rate
256
VTHL
VTLH
AVTH
RIN
tr, tf
TPLH
TPHL
Input Low Threshold Voltage
Input High Threshold Voltage
Receiver Input Hysteresis
Receiver Input Impedance
Rise or Fall Time
Input to Output
Input to Output
1.4 0.8
2.0 1.4
0.1 0.4 1.0
3
5
7
10
400
450
The following tests circuits and timing diagrams are
referenced in the preceding Electrical Characteristics
Tables.
FIGURE 3. RS422 DRIVER TEST CIRCUIT
UNIT CONDITIONS
Kbps
V
V
V
kΩ -15 ≤ VA ≤ 15V
ns (Figures 7, 11 )
ns (Figures 7, 11 )
ns (Figures 7, 11 )
TXB
VOD
RL=50Ω
RL=50Ω VOC
TXA
FIGURE 4. RS422 DRIVER/RECEIVER AC TEST CIRCUIT
33