epc111/112

Fully integrated standalone light barrier driver & receiver

General Description

The epc111/112 is a general purpose, fully integrated self-contained

CMOS circuit family to be used in light-barrier applications.

The chip contains a controller which drives an LED, typically an IR-

LED. The LED is used in a pulsed mode to increase the signal-to-

noise ratio even when there is very strong sunlight biasing the photo

diode.

It contains also a high sensitive photo diode amplifier and a signal

conditioning circuitry to cancel unwanted environmental light including

strong sunlight and pulsed light sources. The receiver is built around a

synchronous demodulator circuitry. Two output signals with different

threshold levels are implemented in order to trigger the light barrier

output or to indicate light reserve.

The chip also includes a power supply circuitry to establish all

internally required voltages from one source only.

It can be used as a standalone device forming the whole core of an

industrial light barrier.

Features



Fully integrated light barrier chip



Needs just a photo diode and a LED with a LED driver



Various types are available, i.e. high sensitivity or high speed



Integrated clock generator



CSP10 package with very small footprint

or standard QFN16 package available

Applications



Light barriers ranging from millimeters to tens of meters



Smoke detectors



Liquid detectors

Functional Block Diagram

for 10-Pin Chip Scale Package (for 16-pin QFN Package)

Functional Block diagram epc70x

LST

OUTH

Parameter

Memory

Interface

OUTN

NC

VDD33

PD

16.12.2010

Page 1

File:

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.

LED

D1

V

LED

f

VDD18

Signal

Processor

Processor

Controller

GND

VDD

LED

9 (12)

10 (10)

7 (15)

4 (4)

1 (9)

VDD

2 (7)

8 (14)

3 (6)

5 (2)

6 (1)

NC

Figure 1: Block Diagram

Type

Response Time

Sensitivity

Typical Application

epc111

Medium

Medium (High)

Long range light barrier

epc112

Fast

Medium

High speed detection rate

Table 1: Characteristics of available types

© 2011 ESPROS Photonics Corporation

Characteristics subject to change without notice

1

Datasheet epc111_112 - V2.2

www.espros.ch