TC245

786-

× 488-PIXEL CCD IMAGE SENSOR

SOCS019A – DECEMBER 1991

Copyright

2-1

POST OFFICE BOX 655303

for NTSC B/W TV Applications

With 1/2” Vidicon Optics

Image-Sensing Area

Burn-in, Residual Imaging, Image

Distortion, Image Lag, or Microphonics

description

The TC245 is a frame-transfer charge-coupled device (CCD) image sensor designed for use in single-chip B/W

NTSC TV applications. The device is intended to replace a 1/2-inch vidicon tube in applications requiring small

size, high reliability, and low cost.

The image-sensing area of the TC245 is configured into 242 lines with 786 elements in each line. Twenty-nine

elements are provided in each line for dark reference. The blooming-protection feature of the sensor is based

on recombining excess charge with charge of opposite polarity in the substrate. This antiblooming is activated

by supplying clocking pulses to the antiblooming gate, which is an integral part of each image-sensing element.

The sensor is designed to operate in an interlace mode, electronically displacing the image-sensing elements

in alternate fields by one-half of a vertical line during the charge integration period, effectively increasing the

vertical resolution and minimizing aliasing. The device can also be operated as a 755 (H) by 242 (V)

noninterlaced sensor with significant reduction in the dark signal.

A gated floating-diffusion detection structure with an automatic reset and voltage reference incorporated on-chip

converts charge to signal voltage. The signal is further processed by a low-noise, state-of-the-art correlated

clamp-sample-and-hold circuit. A low-noise, two-stage, source-follower amplifier buffers the output and

provides high output-drive capability. The image is read out through three outputs, each of which reads out every

third image column.

The TC245 is built using TI-proprietary virtual-phase technology, which provides devices with high blue

response, low dark signal, good uniformity, and single-phase clocking. The TC245 is characterized for operation

from –10

°C to 45°C.

This MOS device contains limited built-in gate protection. During storage or handling, the device leads should be shorted together

or the device should be placed in conductive foam. In a circuit, unused inputs should always be connected to SUB. Under no

circumstances should pin voltages exceed absolute maximum ratings. Avoid shorting OUTn to ADB during operation to prevent

damage to the amplifier. The device can also be damaged if the output terminals are reverse-biased and an excessive current is

allowed to flow. Specific guidelines for handling devices of this type are contained in the publication

Guidelines for Handling

Electrostatic-Discharge-Sensitive (ESDS) Devices and Assemblies available from Texas Instruments.

SUB

1

IAG

2

ABG

3

ADB

4

OUT3

5

OUT2

6

OUT1

7

AMP GND

8

CDB

9

SUB 10

20 SUB

19 IAG

18 ABG

17 SAG

16 SRG3

15 SRG2

14 SRG1

13 NC

12 TRG

11 IDB

DUAL-IN-LINE PACKAGE

(TOP VIEW)

NC – No internal connection

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.