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Complete Product Specifications

Elantec Technical Support:

Features

• Low output noise = 4.0nA/rt-Hz

• High-performance laser diode

driver

• Pin compatible with EL6257

• Voltage-controlled output current

source to 150 mA per channel,

requiring one external set resistor

per channel

• Current-controlled output current

source to 150 mA per channel

• Rise time = 1.0 ns

• Fall time = 1.1 ns

• On chip oscillator with frequency

and amplitude control by use of

external resistors to ground

• Oscillator to 500 MHz

• Oscillator to 100 mA pk/pk

• Single +5V supply (±10%)

• Disable feature for power-up

protection and power savings

• TTL/CMOS control signals

Applications

• DVD-RAM high speed drives

• CD-RW applications

• Writable optical drives

• Laser diode current switching

Ordering Information

Part No

Temp. Range

Package

Outline #

EL6259CU

0°C to +70°C

QSOP-24

MDP0040

EL6259C - Product Brief

Low Noise 4-Channel Laser Diode Driver + Oscillator

General Description

The EL6259C is a low noise four channel laser diode current amplifier

that provides controlled current to a grounded laser diode. The four

amplifiers can provide up to 150 mA per channel of DC or pulsed cur-

rent. Channels 2, 3, and 4 must be used as the write channels, with

switching speeds of approximately one nanosecond rise/fall time. All

user to create multilevel waveforms in order to optimize laser diode

performance. The level of the output current is set by an analog volt-

age applied to an external resistor which converts the voltage into a

An on-chip 500 MHz oscillator is provided to allow current modula-

tion when in the read mode. This is turned on when the EOSC pin is

held high (floating not recommended). 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).

Output current pulses are enabled when an ‘L’ signal is applied to the

OE pin. No output current flows when OE is ‘H’, and additional laser

diode protection is provided since the OE input will float high when

low, which will override the OE control pins.

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

from a current DAC or other current source.

Connection Diagram

1

2

3

4

16

15

14

13

5

6

7

12

11

9

8

10

20

19

18

17

24

23

22

21

GND

GND

RAMP

CE

EOSC

RFREQ

OER

OE2

OE3

OE4

GND

GND

GND

GND