MAX3045BCWE-T Maxim Integrated, MAX3045BCWE-T Datasheet - Page 12

• Manufacturer Part Number: MAX3045BCWE-T
• Description: RS-422/RS-485 Interface IC
• Manufacturer: Maxim Integrated

Specifications of MAX3045BCWE-T

• Data Rate: 20 Mbps
• Operating Supply Voltage: 4.75 V to 5.25 V
• Supply Current: 2 mA
• Operating Temperature Range: 0 C to + 70 C
• Mounting Style: SMD/SMT
• Package / Case: SOIC-16 Wide
• Function: Line Transmitter
• Input Voltage: 4.75 V to 5.25 V
• Maximum Operating Temperature: + 70 C
• Maximum Power Dissipation: 696 mW
• Minimum Operating Temperature: 0 C
• Number Of Drivers: 4
• Output Voltage: - 7.5 V to + 12.5 V
• Product: RS-422/RS-485 Combination
• Propagation Delay Time Ns: 0.7 us

Figure 14 shows a typical multiple-point connection for
the MAX3040–MAX3045 with the MAX3095. Because of
the high frequencies and the distances involved, high
attention must be paid to transmission-line effects while
using termination resistors. A terminating resistor (RT)
is simply a resistor that should be placed at the
extreme ends of the cable to match the characteristic
impedance of the cable. When the termination resis-
tance is not the same value as the characteristic
±10kV ESD-Protected, Quad 5V RS-485/RS-422
Transmitters
Figure 13. Typical Connection of a Quad Transmitter and a Quad Receiver as a Pair
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Typical Multiple-Point Connection
T1IN
T2IN
T3IN
T4IN
EN
EN
MAX3043–MAX3045
V
CC
D1
D2
D3
D4
GND
impedance of the cable, reflections will occur as the
signal is traveling down the cable. Although some
reflections are inevitable due to the cable and resistor
tolerances, large mismatches can cause significant
reflections resulting in errors in the data. With this in
mind, it is very important to match the terminating resis-
tance and the characteristic impedance as closely as
possible. As a general rule in a multi-drop system, termi-
nation resistors should always be placed at both ends of
the cable.
G
G
RT
RT
RT
RT
V
CC
MAX3095
R1
R2
R3
R4
GND
R1OUT
R2OUT
R3OUT
R4OUT