DS2480B+T&R Maxim Integrated Products, DS2480B+T&R Datasheet - Page 25

• Manufacturer Part Number: DS2480B+T&R
• Description: IC LINE DRVR W/SENSOR 1-W 8-SOIC
• Manufacturer: Maxim Integrated Products
• Type: Line Driver, Transmitterr

Specifications of DS2480B+T&R

• Number Of Drivers/receivers: 1/0
• Protocol: RS232
• Voltage - Supply: 4.5 V ~ 5.5 V
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Figure 11a. UART DIRECT
Figure 11b. ±5V RS232
The signals DTR and RTS provide the power to operate the DS2480B. The resistor in the TXD line and
the Schottky diode limit the negative voltage at the TXD pin of the DS2480B to 0.3V maximum. The
resistor is typically 4.7k. If the inverting driver is current-limited to 1mA the resistor is not required.
From the DS2480B’s perspective, this circuit will work with inverted signals of 5V as well as 0 to 5V.
Depending on the voltage levels the host expects, it may be necessary to generate a negative voltage on
the RXD line. Figure 11c shows how this can be accomplished for a true RS232C system.
or μC
UART
or μC
UART
Start
Start
12 V
SOUT (TXD)
SIN (RXD)
L
L
RTS
DTR
1
0
1
0
Regulator
SIN (RXD)
SOUT (TXD)
Power Stealing
M
M
5V
Stop
Stop
With EPROM Programming
* only one DS950x ESD protection device with 5V
VPP
RXD
TXD
DS2480B
GND
VDD
POL
1-W
22 μF
Return
1-Wire Bus
25 of 32
0.1 μF
See Text
5 V
DS9503
DS9503
5V Operation Only
VPP
RXD
TXD
VDD
RXD
TXD
DS2480B
DS2480B
GND
GND
VDD
VPP
POL
POL
1-W
1-W
Optional filter
Optional filter
470 pF
470 pF
62 Ohms
62 Ohms
Return
1-Wire Bus
DS9503
DS9503
*