MAX3120CSA+T Maxim Integrated Products, MAX3120CSA+T Datasheet - Page 5

• Manufacturer Part Number: MAX3120CSA+T
• Description: IC TXRX INFRARED IRDA 8-SOIC
• Manufacturer: Maxim Integrated Products
• Type: Transceiverr

Specifications of MAX3120CSA+T

• Number Of Drivers/receivers: 1/1
• Protocol: Infrared (IRDA)
• Voltage - Supply: 3 V ~ 5.5 V
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

(T
The MAX3120 is an IrDA 1.2-compatible infrared (IR)
transceiver. By selecting appropriate external optical
components (see
section), the MAX3120 will operate at data rates of
2.4kbps to 115kbps at distances from 1cm to 1m.
Because of its low-noise design, the MAX3120
achieves a bit error rate (BER) below 10
data rates when used with the appropriate external
components. On-chip filtering rejects out-of-band
ambient light signals that would otherwise interfere with
IR communication. Also included in the MAX3120 is
a high-power LED driver capable of sinking 200mA. It
can drive most available IR LEDs at IrDA speeds of
2.4kbps to 115kbps.
A
PIN
= +25°C, unless otherwise noted.)
1
2
3
4
5
6
7
8
2V/div
2V/div
NAME
SHDN
PGND
LEDC
GND
PINC
V
TERMIC BPV22NF, TRANSMIT POWER 200mW/sr
RXD
TXD
V
CC
CC
= 3.3V, 115.2kbps AT 1m DISTANCE,
IR LED and PIN Photodiode Selection
_______________________________________________________________________________________
vs. INFRARED INPUT
IR Transmitter TTL/CMOS Data Input. High = LED on.
Supply Voltage
Ground. Connect anode of PIN diode to GND. Connect GND to PGND.
PIN Diode Cathode Input. Connect cathode of PIN diode to PINC.
Shutdown Input. Active low.
Power Ground. Ground for IR LED driver. Connect PGND to GND.
LED Driver Output. Connect cathode of IR-emitting LED to LEDC.
IR Receiver TTL/CMOS Data Output. Pulses low for IR input pulse.
Detailed Description
RXD OUTPUT
2 s/div
MAX3120 toc12
-8
Typical Operating Characteristics (continued)
RXD
OUTPUT
at maximum
INFRARED
INPUT
IrDA Infrared Transceiver
Low-Profile, 3V, 120µA,
The MAX3120’s IR receiver amplifier reverse biases the
PIN diode by approximately 1.2V, and the PIN diode
converts pulses of IR light into pulses of current. The
input transimpedance (current-to-voltage) amplifier
then converts these current pulses into voltage pulses
of a useful magnitude. The MAX3120 filters the result-
ing output voltage pulses to remove low-frequency
ambient light interference and high-frequency circuit
noise. Finally, a high-speed comparator translates
these voltage pulses into usable CMOS output levels
(Figure 1).
FUNCTION
2V/div
2V/div
V
TERMIC BPV22NF, TRANSMIT POWER 200mW/sr
CC
= 3.3V, 2400bps AT 1m DISTANCE,
vs. INFRARED INPUT
RXD OUTPUT
100 s/div
Pin Description
MAX3120 toc13
RXD
OUTPUT
INFRARED
INPUT
Receiver
5