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SP8107

Rev. 09/05/03

SP8107 – Three Channel Laser Driver

Copyright 2003 Sipex Corporation

SIPEX RESERVES THE RIGHT TO MAKE CHANGES TO THIS DATASHEET. CALL FOR UPDATES: 1-978-667-8700.

SIPEX CONFIDENTIAL, ADVANCED & PROPRIETARY. DO NOT DISTRIBUTE OR

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IR

I2

I3

RF

EN2

EN3

ENABLE

OSCEN

Vcc

Iout A

GND

RSA

RSB

Iout B

SELA

Vcc

SP8107

SSOP-16

FEATURES

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Three current controlled inputs with independent

ENABLE/DISABLE

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Two selectable outputs for grounded laser diodes

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Output current up to 400mA (250mA per input channel)

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Independent swing for each output channel controlled

by external resistor

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On-chip oscillator with resistor controlled frequency

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Single 5V power supply

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Common ENABLE and oscillator ENABLE inputs

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TTL/CMOS logic level control signals

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Small SSOP16 package

APPLICATION

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DVD-RAM with CD-RW capability

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DVD-RW with CD-RW capability

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Writable data storage optical devices

GENERAL DESCRIPTION

The SP8107 is a three channel laser diode driver specifically designed for high speed DVD-RW or DVD-

RAM applications. It operates two grounded laser diodes (650nm for DVD and 780nm for CD) and

features three input channels that allow setting of three different optical power levels. The first channel

(IR) has lower gain (100mA/mA) and output current (up to 200mA) and is used as a read channel. The

second (I2) and third (I3) channels have higher gain (250mA/mA) and output current (up to 250mA) and

are used as write channels. Each write channel may be switched on/off at very fast switching speeds with

TTL/CMOS logic level signals applied to EN2 and EN3 inputs - channels are enabled at low logic level

and disabled at high logic level. Outputs of all channels are summed together and connected to one of the

200 ohm DC impedance but allow voltage control by using external limiting resistors.

An on-chip oscillator is used to reduce laser mode hopping in read mode. The frequency of this oscillator

may be changed by an external resistor connected to the RF pin. Oscillator swing can be set separately for

enabled by high logic level at the OSCEN pin.

Low logic level at the ENABLE pin disables the entire device. Supply current in disabled mode is below

100uA. Pins EN2 and EN3 have internal pull-up resistors. Pins ENABLE, OSCEN, and SELA have

internal pull-down resistors.

Three Channel High Performance Laser Driver