Document Number: 82579

www.vishay.com

Revision 05-July-02

2

Table 1. Input/Output Functional Description

Symbol

I/O Type

Polarity

Function

RxD

Output

Active

Low

This output indicates received serial data. It is a push-pull CMOS driver capable of driv-

ing a standard CMOS or TTL load. No external pull-up or pull-down resistor is required.

This output may switch indeterminately when the module is transmitting. This output pin

is in tri-state mode when the module is in shutdown mode and during digital serial pro-

gramming operations. RxD is high at initializaton.

TxD

Input

Active

High

This CMOS input is used to transmit serial data when SD/ Mode is low. An on-chip pro-

tection circuit disables the LED driver if the TxDpin is asserted for longer than 60

µs.

When used in conjunction with the SD/ Mode pin. TxD is low at initializaton.

SD/ Mode Input

Active

High

Assertion of this pin high for a period of time exceeding 400

µs places the module into

shutdown mode. On the falling edge of this signal, the state of the TxDpin is sampled and

used to set receiver low bandwidth (TxD= Low) or high bandwidth (TxD= High) mode.

See Figures 7 and 8 for timings. SD is low at initializaton

Positive Supply

-

Connect to positive power supply (2.7 V to 5.25 V). Placement of a 1.0

µF to 10.0 µF de-

GND

Ground (Power)

-

Connect to power supply ground. A solid ground plane is recommended.

NC

No Connect

-

This pin could be connected to ground.

Input

-

Output

-

LED cathode. Leave this pin unconnected. This pin may be monitored to determine the

state of the LED.

Figure 1. Block Diagram

Figure 2. Minimum Vishay Low-Power Integrated Infrared

Transceiver Circuit Diagram

Comp

Amp

TxD

GND

LEDC

RxD

Driver

SD/Mode

Mode &

Power

Control

LEDA

Driver

IR

Controller

IRMS6452

IRTX

TxD

SD/ Mode

LEDA

V

GND

IRRX

RxD

GPO

LEDC

NC

CC

C1= 1

µF to 10 µF

Table 2. Recommended Operating Conditions

Table 3. DC Electrical Characteristics

Table 4. Receiver DC Electrical Characteristics

Symbol

Parameter

Min

Typical

Max

Unit

Conditions

V

CC

Supply Voltage

2.7

5.25

V

T

A

Ambient Operating

Temperature

-25

75

˚C

Symbol

Parameter

Min

Typical

Max

Unit

Conditions

I

CC

Supply Current; Listening

2.0

3.2

4.5

mA

Typical value obtained at Vcc=5 V

I

CC

Supply Current; Receiving

3.8

15

mA

Interface and optical input power dependent

I

SD

Supply Current; Shutdown

50

100

nA

V

Symbol

Parameter

Min

Typical

Max

Unit

Conditions

V

OL

RxD Output Low Voltage

0.5

V

I

OL

Static Sink Current on RxD

2.4

mA

2.2K

V

OH

RxD Output High Voltage

Vcc-0.5

V

I

OH

Static Source Current on RxD

2.4

mA

2.2K

RL

RxD Rosistive Load

2.2

k

Ω

C

L

RxD Capacitive Load

50

pF