19-1402; Rev 0; 11/98
3 V t o 5 .5 V, IrDA In fra re d Tra n s c e ive r w it h
In t e g ra t e d RS -2 3 2 In t e rfa c e
0/MAX31
Ge n e ra l De s c rip t io n
Fe a t u re s
The MAX3130/MAX3131 combine an IrDA 1.2 compati-
ble infrared transceiver with an RS-232 interface—all in
a single 3V-powered hybrid microcircuit. The infrared
tra ns c e ive r s up p orts IrDA d a ta ra te s of 2.4kb p s to
115kbps. The infrared receive channel provides a high-
gain/low-noise PIN-diode amplifier with 100µA of ambi-
ent photodiode current rejection at a +3V supply. A
high-power LED driver capable of sinking 200mA is
included in the infrared transmit path. The on-board
encoder/decoder (ENDEC) compresses/stretches sig-
nals to and from the external UART, allowing IrDA com-
munication even with non-IrDA UARTs.
♦ Integrated RS-232 and IrDA in Single 28-Pin SSOP
Package
♦ 370µA Supply Current
♦ IrDA 1.2 Compatible: 2.4kbps to 115kbps
Data Rate
♦ On-Board IR Encoder/Decoder Allows Use of
Non-IrDA UARTs
♦ +3.0V to +5.5V Single-Supply Operation
♦ Meet EIA/TIA-232 Specifications Down to +3V
♦ 200mA, High-Current Infrared LED Drive
A 2-driver/2-receiver RS-232 transceiver supports data
rates up to 120kbps. A proprietary, high-efficiency, dual
charge-pump power supply and a low-dropout trans-
mitter combine to deliver true RS-232 performance from
a single +3.0V to +5.5V supply. Selectable shutdown
for IR and RS-232 circuitry reduces supply current to
1µA.
♦ 1µA Low-Power Shutdown with RS-232
Receivers Active
Ord e rin g In fo rm a t io n
PART
TEMP. RANGE
0°C to +70°C
-40°C to +85°C
0°C to +70°C
-40°C to +85°C
PIN-PACKAGE
28 SSOP
The MAX3130 is optimized for applications using a sin-
gle UART for both infrared and RS-232 communication.
The infrared transmitter input and infrared receiver out-
put are multiplexed with one RS-232 transmitter input
a nd one RS-232 re c e ive r outp ut, re s p e c tive ly. The
MAX3131’s IrDA transceiver and RS-232 transceivers
are separate and have their own data inputs and outputs.
MAX3130CAI
MAX3130EAI
MAX3131CAI
MAX3131EAI
28 SSOP
28 SSOP
28 SSOP
P in Co n fig u ra t io n
Both these devices require a minimum of external com-
ponents: four small 0.1µF capacitors, a photodiode, an
infrared LED, and a current-setting resistor.
TOP VIEW
EDGEDET (RXD)
1
2
28 R2OUT
27 R2IN
26 T2OUT
25 RSSD
24 V-
T1IN
T2IN
Ap p lic a t io n s
3
Personal Digital Assistants (PDAs)
Palmtop Computers
Battery-Powered Systems
Hand-Held Equipment
Peripherals
IRMODE (TXD)
R1OUT
4
5
MAX3130
MAX3131
R1IN
6
23 C2-
T1OUT
7
22 C2+
21 C1-
BAUD16
GND
8
IrDA Applications
9
20 C1+
19 V+
Cellular Phones
V
CC
10
N.C. 11
18 N.C.
17 LEDC
16 PGND
15 IRSD
AV 12
CC
AGND 13
PINC 14
SSOP
( ) ARE FOR MAX3131
________________________________________________________________ Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.