Datasheet

MAX3130/MAX3131
3V to 5.5V, IrDA Infrared Transceiver with
Integrated RS-232 Interface
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Pin Description (continued)
TTL/CMOS RS-232 Receiver Output. For the MAX3130, drive IRMODE low to connect
R2OUT to the IR receiver output, and drive IRMODE high to connect R2OUT to the
RS-232 receiver output. For the MAX3131, R2OUT is always internally connected to the
RS-232 receiver output.
R2OUT2828
RS-232 Receiver InputR2IN2727
RS-232 Transmitter OutputT2OUT2626
Shutdown Input for the RS-232 Transmitters and Charge Pump
RSSD
2525
-5.5V Generated by the Internal Charge PumpV-2424
Negative Terminal of the Inverting Charge-Pump CapacitorC2-2323
Positive Terminal of the Inverting Charge-Pump CapacitorC2+2222
Negative Terminal of the Voltage-Doubling Charge-Pump CapacitorC1-2121
Positive Terminal of the Voltage-Doubling Charge-Pump CapacitorC1+2020
Shutdown Input for the IrDA Transceiver Circuitry
IRSD
1515
Analog Ground for IR Signal Processing. Connect to GND.AGND1313
Analog Supply Voltage V
CC
for IR Signal Processing. AV
CC
range is 3.0V to 5.5V.AV
CC
1212
Silicon PIN Photodiode Input. Connect PINC to the cathode of the PIN photodiode.
Connect the anode of the PIN photodiode to GND.
PINC1414
Open-Drain Output for Driving the IR LED. Connect LEDC to the cathode of the IR LED.LEDC1717
Power Ground for IR LED Driver. Connect to GND.PGND1616
+5.5V Generated by the Internal Charge PumpV+1919
No Connection. Do not make connections to these pins.
N.C.11, 1811, 18
6
7
8
9
10
MAX3131
3
4
5
MAX3130
PIN
RS-232 Receiver InputR1IN6
RS-232 Transmitter OutputT1OUT7
16-Times Baud-Rate Input. To use the ENDEC, apply a signal that is 16 times the baud
rate into BAUD16. Connect BAUD16 to GND or V
CC
to disable the ENDEC.
BAUD168
GroundGND9
3.0V to 5.5V Supply VoltageV
CC
10
TTL/CMOS RS-232 Transmitter Input. For the MAX3130, drive IRMODE low to connect
T2IN to the IR transmitter input, and drive IRMODE high to connect T2IN to the RS-232
transmitter input. For the MAX3131, T2IN is always connected to the RS-232 transmitter
input.
T2IN3
IR Transmitter TTL/CMOS Data InputTXD—
TTL/CMOS RS-232 Receiver OutputR1OUT5
FUNCTIONNAME
—
IR Mode Control. Drive IRMODE low to connect R2OUT to the IR receiver output and
T2IN to the IR transmitter input. Driving IRMODE low also shuts down the RS-232
charge pump and puts the RS-232 transmitter outputs in a high-impedance state. Drive
IRMODE high to connect R2OUT to the RS-232 receiver output and connect T2IN to the
RS-232 transmitter input.
IRMODE
4