iC-WG

14-BIT DIFFERENTIAL SCANNING OPTO ENCODER

Rev B0, Page 2/11

DESCRIPTION

The iC-WG is an optoelectronic detector IC for linear and angle measuring systems, e.g. glass scales or

rotary encoders. Monolithically integrated are photodiodes, amplifiers and comparators as well as

TTL-compatible push-pull output drivers. All 14 tracks are differentially evaluated.

An integrated LED current control with driver stage makes it possible to directly connect a transmit LED

with series resistor and also guarantees a constant optical received power. The setpoint for the receive

current is adjusted via an external resistor. If the LED current control deviates from its working range, this

is indicated at the error message output.

For the adjustment of a reticle the chip features two adjustment crosses and supplies the analog signals

from three monitor photocurrent amplifiers. For exact radial alignment of the iC-WG (with reticle) to the

code disk, two monitor photodiodes are arranged such that the track position can be checked (option, not

available in the standard SMD package).

Two test pins permit a complete electrical functional test of the IC not including the photodiodes.

All push-pull and analog outputs are protected against ESD and short-circuits. The error message output

NERR is also short-circuit-proof and due to it’s open-collector design bus capable.

PAD DESCRIPTION

Name

Function

GND

Ground

IN0

Track N0 Analog Output (current sink)

IP0

Track P0 Analog Output (current sink)

IN1

Track N1 Analog Output (current sink)

IP1

Track P1 Analog Output (current sink)

RGND

Reference Ground for RSR circuitry

RSR

LED Current Control Setup

LED

LED Driver Output

LGND

LED Driver Power Ground

NERR

Error Message Output, low active

CSR

External capacitor for LED control

TIP

Positive Test Aid Input

TIN

Negative Test Aid Input

VCC

+5 to +20V Supply Voltage

A13

Track 13 Push-Pull Output

A12

"

..

"

A0

Track 0 Push-Pull Output