ELANT EL6287CU Datasheet

EL6287C - Product Brief

4-Ch Laser Diode Driver + Oscillator

EL6287C - Product Brief

Features

• “Shrink-Small” Outline Package

• Voltage-controlled output current source requiring one external set resistor per channel

• Current-controlled output current source

• Rise time = 0.8 nsec

• Fall time = 0.8 nsec

• On chip oscillator with frequency and amplitude control by use of external resistors to ground

• Oscillator to 500MHz

• Oscillator to 100mA pk/pk

• Single +5V supply (±10%)

• Disable feature for power-up protection and power savings

• CMOS control signals

Applications

• CD-RW applications

• Writable optical drives

• Laser diode current switching

Ordering Information

Part No Temp. Range Package Outline #

EL6287CU 0°C to +70°C 24-Pin QSOP MDP0040

General Description

The EL6287C is a four channel laser diode current amplifier that provides controlled current to a grounded laser diode. Channels 2, 3, and 4 must be used as the write channels, with switching speeds of approximately one nanosecond rise/fall time. All four channels are summed together at the I

output, allowing the user to create multilevel

OUT

waveforms in order to optimize laser diode performance. The level of the output current is set by an analog voltage applied to an external resistor which converts the voltage into a current at the IIN pin (virtually ground). The current seen at this pin is then amplified to become a current source at pin I

OUT

An on-chip 500MHz oscillator is provided to allow current modulation when in read mode. This is turned on when the OSCEN pin is held high. Complete control of amplitude and frequency is set by two external resistors connected to ground at pins RFREQ and RAMP (see graphs in this data sheet for further explanation). The oscillator will turn off whenever any of the OUTEN pins for channels 2, 3, or 4 (the write channels) are low (see truth table).

The external resistors allow the user to accurately and independently set each amplifier transconductance by applying a voltage to each resistor, without restriction on the voltage range, thus ensuring broad voltage DAC compatibility. Alternatively, the IIN pin can be biased from a current DAC or other current source.

Connection Diagram

GND

IINR

GND

IIN2

RFREQ

IIN3

IIN4

OUTENR

OUTEN2

OUTEN3

OUTEN4

GND

VCC

IOUT

GND

RAMP

ENABLE

OSCEN

VCC

GND

August 31, 2001

Note: All information contained in this data sheet has been carefully checked and is believed to be accurate as of the date of publication; however, this data sheet cannot be a “controlled document”. Current revisions, if any, to these

specifications are maintained at the factory and are available upon your request. We recommend checking the revision level before finalization of your design documentation.

EL6287C - Product Brief

4-Ch Laser Diode Driver + Oscillator

EL6287C - Product Brief

General Disclaimer

Specifications contained in this data sheet are in effect as of the publication date shown. Elantec, Inc. reserves the right to make changes in the circuitry or specifications contained herein at any time without notice. Elantec, Inc. assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement.

WARNING - Life Support Policy

Elantec, Inc. products are not authorized for and should not be used within Life Support Systems without the specific written consent of Elantec, Inc. Life Support systems are equipment intended to sup-

Elantec Semiconductor, Inc.

675 Trade Zone Blvd. Milpitas, CA 95035 Telephone: (408) 945-1323

(888) ELANTEC Fax: (408) 945-9305 European Office: +44-118-977-6020 Japan Technical Center: +81-45-682-5820

port or sustain life and whose failure to perform when properly used in accordance with instructions provided can be reasonably expected to result in significant personal injury or death. Users contemplating application of Elantec, Inc. Products in Life Support Systems are requested to contact Elantec, Inc. factory headquarters to establish suitable terms & conditions for these applications. Elantec, Inc.’s warranty is limited to replacement of defective components and does not cover injury to persons or property or other consequential damages.

August 31, 2001

Printed in U.S.A.