卤80V Fault-Protected, 2Mbps, Low Supply
Current CAN Transceivers
MAX3050/MAX3057
CANH - CANL
1V/div
CANH - CANL
1V/div
FFT
200mV/div
FFT
200mV/div
Figure 8. FFT Recessive Bus at 500kbps
Figure 10. FFT Recessive Bus at 62.5kbps
Applications Information
CANH - CANL
1V/div
Reduced EMI and Reflections
In slope-control mode, the CANH and CANL outputs
are slew-rate limited, minimizing EMI and reducing
reflections caused by improperly terminated cables. In
general, a transmitter鈥檚 rise time relates directly to the
length of an unterminated stub, which can be driven
with only minor waveform reflections. The following
equation expresses this relationship conservatively:
Length = t
RISE
/ (15ns/ft)
FFT
500mV/div
Figure 9. FFT Dominant Bus at 62.5kbps
where t
RISE
is the transmitter鈥檚 rise time.
The MAX3050 and MAX3057 require no special layout
considerations beyond common practices. Bypass V
CC
to GND with a 0.1碌F ceramic capacitor mounted close
to the IC with short lead lengths and wide trace widths.
Chip Information
TRANSISTOR COUNT: 1214
PROCESS: BiCMOS
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