Rev 0.8 (09/25/06)

SP8036 APC Amplifier



2006 Sipex Corporation

page

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Vref

Rgain1

Rgain2

CE

SP8036

8-Pin

OPLGA

Vcc

Gain

Vout

Gnd

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FEATURES

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Dual wavelength 650nm and 780nm

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13 ns Settling Time to 2%

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100 MHz Bandwidth at -3dB

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10 mV Output Offset Voltage

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25 µV/

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± 6 dB External Gain Adjust

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Small 8-pin OPLGA package

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Power-down mode

APPLICATIONS

CD-R, and CD-RW

DVD+/-R, DVD+/-RW, and DVD-

RAM

GENERAL DESCRIPTION

The SP8036 represents the next generation in Automatic Power Control (APC) amplifiers designed

specifically for demanding pick-up head applications. With its integrated photo detector, the SP8036 monitors

light intensity of the laser diode in CD-R, CD-RW, DVD+/-R, DVD+/-RW, and DVD-RAM assemblies and

converts this light to an output voltage. The magnitude of this voltage signal corresponds to the laser power

intensity and is subsequently fed back to the laser diode driver to control the laser output power.

The SP8036 on-chip photo detector transforms incident laser light into a proportional current, which is then

converted to a voltage through a transimpedance amplifier. Adjustable gain is provided in the transimpedance

amplifier by means of a gain control loop that is controlled by an external resistor. This external resistor is not

a part of the signal path, which greatly reduces the effects of all parasitic capacitances and inductances on

the flex cable at these pins. The signal is then buffered to provide reactive load drive capability.

The SP8036 achieves an unparalleled level of performance by combining excellent DC stability and low noise

with outstanding AC performance. This level of performance is achieved using a proprietary fully

complimentary BICMOS process with fully integrated, on-board photo detector.

The SP8036 is offered with a nominal sensitivity 4450 V/W and is packaged in a 3.0 x 3.5 mm, 8-lead

OPLGA package. All input logic levels should not be left open at any time.

The SP8036 offers power-down capability with the new active-low chip enable pin, CE. The chip operates

normally when this pin is connected to GND and powers down when connected to Vcc.

Solved by

TM

SP8036

APC Amplifier with Integrated Photodiode

and Gain Adjust Capability