2000 January

13

Philips Semiconductors

Objective specification

Frame Transfer CCD Image Sensor

FXA 1012

Peripheral ICs

To allow compact and low-cost applications, use of the following

peripheral circuits for the FXA 1012 is suggested:

• Pulse Pattern Generator

The PPG (pulse pattern generator) delivers all the pulses, at logic

level, to drive the vertical clocks of the CCD. For this sensor, the

PPG is included in the DSP SAA8122 or separately in the Timing

Generator SAA8103.

• Vertical Drivers + DC/DC Converter

The vertical drivers convert the 3.3V or 5V logic pulses from the

PPG to 12V analog pulses to drive the vertical clocks of the CCD.

The recommended driver is the Philips TDA9991.

• CDS - AGC - ADC

The combined CDS (correlated double sampling) - AGC (automatic

gain control) and ADC (10 bit analog-to-digital convertor) is the

easiest way to link the output of the CCD to a DSP (digital signal

processor). Philips Semiconductors # TDA8783

• DSP

A dedicated DSP has been developed that can handle the image

for mat and different modes of the FXA 1012. Philips

Semiconductors # SAA8122.

Special modes of operation

Monitor mode with 240 lines vertical resolution is achieved with 1:5

subsampling, yielding 1200/5 = 240 lines. When 1:4 subsamlping is

applied, an image with 288 lines vertical resolution is obtained.

Device Handling

An image sensor is a MOS device which can be destroyed by electro-

static discharge (ESD). Therefore, the device should be handled

with care.

Always store the device with short-circuiting clamps or on conductive

foam. Always switch off all electric signals when inserting or removing

the sensor into or from a camera (the ESD protection in a CCD

image sensor is less effective than the ESD protection of standard

CMOS circuits).

Being a high quality optical device, it is important that the cover

glass remain undamaged. When handling the sensor, use fingercots.

To remove the protective tape from the cover glass, use the following

procedure:

• do not scratch or tear off the protective tape before mounting.

• peel off the tape slowly.

• the use of an ionised air blower is recommended when peeling off

the tape.

• once peeled off, do not reuse the tape.

To clean stains from the package surface, use a cotton stick soaked

in ethanol. Wipe carefully in order not to scratch the glass surface.

Dry rubbing of the cover glass may cause electro-static discharges

which can destroy the device.

Soldering information

The CCD package temperature must not exceed 150°C. Soldering

iron temperature should be under 300°C when mounting a CCD on

a printed circuit board. Aim for a soldering time of 3 seconds per

pad. Use a soldering iron that has an adjustable temperature control

function (that is grounded) that holds the soldering iron tip at a

constant temperature.