Datasheet UPD3794CY Datasheet (NEC)

DATA SHEET

MOS INTEGRATED CIRCUIT

µ

PD3794

2700 PIXELS × 3 COLOR CCD LINEAR IMAGE SENSOR

The µPD3794 is a color CCD (Charge Coupled Device) linear image sensor which changes optical images to

electrical signal and has the function of color separation.

µ

PD3794 has 3 rows of 2700 pixels, and each row has a single-sided readout type of charge transfer register.

The
And it has reset feed-through level clamp circuits, a clamp pulse generation circuit, an RGB selector and voltage
amplifiers. Therefore, it is suitable for 300 dpi/A4 color image scanners, color facsimiles and so on.

FEATURES

• Valid photocell : 2700 pixels × 3

• Photocell's pitch : 8 µm

• Line spacing : 32 µm (4 lines) Green line-Blue line, Blue line-Red line

7

• Color filter : Primary colors (red, green and blue), pigment filter (with light resistance 10

• Resolution : 12 dot/mm A4 (210 × 297 mm) size (shorter side)

300 dpi US letter (8.5” × 11”) size (shorter side)

• Drive clock level : CMOS output under 5 V operation

• Data rate : 4 MHz MAX.

• Power supply : +12 V

• On-chip circuits : Reset feed-through level clamp circuits

Clamp pulse generation circuit
RGB selector
Voltage amplifiers

lx•hour)

ORDERING INFORMATION

Part Number Package

µ

PD3794CY CCD linear image sensor 22-pin plastic DIP (400 mil)

Document No.S13125EJ1V0DS00(1st edition)
Date published December 1997 N CP(K)
Printed in Japan

The information in this document is subject to change without notice.

©

1997

BLOCK DIAGRAM

µ

PD3794

SEL1

SEL2 GND GNDV

22120

V

OUT

Clamp pulse
generator

OD

19 2 11 15 14

······

D15

······

D15

······

D15

3

φ

RB

D64

CCD analog shift register

D64

CCD analog shift register

D64

CCD analog shift register

Photocell

S1

S2

(Green)

Transfer gate

Photocell

S1

S2

(Blue)

Transfer gate

Photocell

S1

S2

(Red)

Transfer gate

S2699

S2700

S2699

S2700

S2699

S2700

D65

D65

D65

D66

D66

D66

D67

D67

D67

φ

GND 1

9

φ

2

13

12

10

φ

TG1

(Green)

φ

TG2

(Blue)

φ

TG3

(Red)

2

PIN CONFIGURATION (Top View)

Green photocell array

8 m

µ

Blue photocell array

8 m

µ

Red photocell array

8 m

µ

4 lines

(32 m)

µ

4 lines

(32 m)

µ

CCD linear image sensor 22-pin plastic DIP (400 mil)

µ

PD3794

Output signal

Ground

Reset gate clock

No connection

No connection

No connection

No connection

No connection

Shift register clock 2

Transfer gate clock 3
(for Red)

Ground

V

GND

φ

φ

TG3

GND

OUT

RB

NC

NC

NC

NC

NC

φ

1

2

1

1

1

3

4

5

6

Red

Blue

Green

7

8

9

2

10

2700

2700

2700

11

22NCSEL1

21

NC

SEL2

20

V

19

18

17

NC

16

NC

GND

15

14

φ

φ

13

12

φ

RGB select input 1

No connection

RGB select input2

Output drain voltage

OD

No connection

No connection

No connection

Ground

1

Shift register clock 1

Transfer gate clock 1

TG1

(for Green)

Transfer gate clock 2

TG2

(for Blue)

PHOTOCELL STRUCTURE DIAGRAM PHOTOCELL ARRAY STRUCTURE DIAGRAM

(Line spacing)

3

m

µ

Channel stopper

5 m

µ

Aluminum
shield

µ

8 m

3

ABSOLUTE MAXIMUM RATINGS (TA = +25 °C)

Parameter Symbol Ratings Unit

Output drain voltage VOD –0.3 to +15 V

µ

PD3794

Shift register clock voltage V
Reset gate clock voltage V
Transfer gate clock voltage V

φ

1, Vφ2 –0.3 to +8 V

φ

RB –0.3 to +8 V

φ

TG1

to V

φ

TG3 –0.3 to +8 V

RGB select input voltage VSEL1,VSEL2 –0.3 to +8 V
Operating ambient temperature TA –25 to +60 °C
Storage temperature Tstg –40 to +70 °C

Caution Exposure to ABSOLUTE MAXIMUM RATINGS for extended periods may affect device reliability;

exceeding the ratings could cause permanent damage. The parameters apply independently.

RECOMMENDED OPERATING CONDITIONS (TA = +25 °C)

Parameter Symbol MIN. TYP. MAX. Unit
Output drain voltage VOD 11.4 12.0 12.6 V
Shift register clock high level V
Shift register clock low level V
Reset gate clock high level V
Reset gate clock low level V
Transfer gate clock high level V
Transfer gate clock low level V
RGB select input high level VSEL1H, VSEL2H 4.5 5.0 5.5 V

φ

1H, Vφ2H 4.5 5.0 5.5 V

φ

1L, Vφ2L –0.3 0 +0.5 V

φ

RBH 4.5 5.0 5.5 V

φ

RBL –0.3 0 +0.5 V

φ

TG1H

φ

TG1L

to V

φ

TG3H 4.5 V

to V

φ

TG3L –0.3 0 +0.5 V

Note

φ

1H

Note

V

φ

1H

V

RGB select input low level VSEL1L, VSEL2L –0.3 0 +0.5 V
Data rate f

Note When Transfer gate clock high level (V

φ

RB – 1.0 4.0 MHz

φ

TG1H to VφTG3H) is higher than Shift register clock high level (Vφ1H),

Image lag can increase.

4

ELECTRICAL CHARACTERISTICS

µ

PD3794

TA = +25 °C, VOD = 12 V, data rate (f

φ

RB) = 1 MHz, storage time = 10 ms,

light source: 3200 K halogen lamp +C-500S (infrared cut filter, t = 1mm), input signal clock = 5 Vp-p

Parameter Symbol Test Conditions MIN. TYP. MAX. Unit
Saturation voltage Vsat 2.0 3.0 V
Saturation exposure Red SER 0.205 lx•s

Green SEG 0.225 lx•s

Blue SEB 0.375 lx•s
Photo response non-uniformity PRNU VOUT = 1.0 V 6 20 %
Average dark signal ADS Light shielding 0.5 5.0 mV
Dark signal non-uniformity DSNU Light shielding 4.0 10.0 mV
Power consumption PW 300 600 mW
Output impedance ZO 0.5 1 kΩ
Response Red RR 10.3 14.6 18.9 V/lx•s

Green RG 9.4 13.3 17.2 V/lx•s

Blue RB 5.6 8.0 10.4 V/lx•s
Image lag IL VOUT = 1.0 V 5.0 10.0 %
Offset level
Output fall delay time

Note1

Note2

VOS 4.5 6.0 7.5 V
td VOUT = 1.0 V 70 ns

Total transfer efficiency TTE VOUT = 1.0 V, 92 98 %

data rate = 4 MHz

Response peak Red 630 nm

Green 540 nm

Blue 460 nm
Dynamic range DR1 Vsat /DSNU 750 times

DR2 Vsat /σ 3000 times
Reset feed-through noise
Random noise σ Light shielding – 1.0 – mV

Note1

RFTN Light shielding –1000 –300 +500 mV

Notes 1. Refer to TIMING CHART 2.

2. When the fall time of

φ

1 (t1) is the TYP. value (refer to TIMING CHART 2).

5

INPUT PIN CAPACITANCE (TA = +25 °C, VOD = 12 V)

Parameter Symbol Pin name Pin No. MIN. TYP. MAX. Unit

µ

PD3794

Shift register clock pin capacitance 1 C
Shift register clock pin capacitance 2 C
Reset gate clock pin capacitance C
Transfer gate clock pin capacitance C

φ

1

φ

2

φ

RB

φ

TG

φ

1 14 300 pF

φ

2 9 300 pF

φ

RB 3 20 pF

φ

TG1 13 50 pF

φ

TG2 12 50 pF

φ

TG3 10 50 pF

RGB select input pin capacitance CSEL SEL1 22 50 pF

SEL2 20 50 pF

RGB SELECT FUNCTION

RGB select input

SEL1 SEL2
High level High level Blue
High level Low level Green
Low level High level Red
Low level Low level Prohibited

Output color

6

123456789101112131415

6162636465

66

2763

2764

2765

2766

2767

2768

2769

SEL2

SEL1

φ

TG1 to

TG3

φ

1

2

φ

φ

RB

φ

V

OUT

a

b

(Blue)

Optical black

(48 pixels)

Invalid photocell

(2 pixels)

Valid photocell (2700 pixels)

Invalid photocell

(3 pixels)

Note

Note

Note

φ

RB pluse continuously during this period, too.Input the

TIMING CHART 1-1

16

7

µ

PD3794

8

123456789101112131415

6162636465

66

2763

2764

2765

2766

2767

2768

2769

SEL2

SEL1

φ

TG1 to

TG3

φ

1

2

φ

φ

RB

φ

V

OUT

b

c

(Green)

Optical black

(48 pixels)

Invalid photocell

(2 pixels)

Valid photocell (2700 pixels)

Invalid photocell

(3 pixels)

Note

Note

Note

φ

RB pluse continuously during this period, too.Input the

TIMING CHART 1-2

16

µ

PD3794

123456789101112131415

6162636465

66

2763

2764

2765

2766

2767

2768

2769

SEL2

SEL1

φ

TG1 to

TG3

φ

1

2

φ

φ

RB

φ

V

OUT

c

a

(Red)

Optical black

(48 pixels)

Invalid photocell

(2 pixels)

Valid photocell (2700 pixels)

Invalid photocell

(3 pixels)

Note

Note

Note

φ

RB pluse continuously during this period, too.Input the

TIMING CHART 1-3

16

9

µ

PD3794

TIMING CHART 2 (for each color)

φ

µ

PD3794

t2t1

φ

1

φ

2

t5

φ

RB

V

OUT

φ

TG1 to φTG3, φ1, φ2 TIMING CHART

90 %

10 %

φ

TG1 to TG3

φ

t6

t3

90 %

10 %

90 %

10 %

t4

+

t

10 %

90 %

10 %

t10

d

t8

t7

RFTN

RFTN

_

t9

t11

OS

V

φ

1, φ2 cross points

90 %

φ

1

φ

2

Symbol MIN. TYP. MAX. Unit
t1, t2 0 25 ns
t3 30 50 ns
t4 150 250 ns
t5, t6 0 25 ns
t7 3000 10000 ns
t8, t9 0 50 ns
t10, t11 900 1000 ns

φ

1

2 V or more 2 V or more

2

Remark Adjust cross points of φ1 and φ2 with input resistance of each pin.

10

µ

PD3794

APPLICATION TIMING EXAMPLE (for reference)

The µPD3794 can be operated under the following timing to switch Red, Green, and Blue outputs and get each
color data in a 1-pixel period. However the offset level of each color is not the same. Therefore, offset level
compensation is required to each color by using each color’s data at dark or the optical black pixels.

The following timing and parameters are for reference only.

SEL1

SEL2

φ

φ

φ

RB

V

OUT

t

R

1

2

t

G

t

B

at dark

with light

Red Green Blue

Symbol MIN. TYP. MAX. Unit
tR, tG, tB 300 – ns

11

DEFINITIONS OF CHARACTERISTIC ITEMS

1. Saturation voltage: Vsat
Output signal voltage at which the response linearity is lost.

2. Saturation exposure: SE
Product of intensity of illumination (I

3. Photo response non-uniformity: PRNU
The output signal non-uniformity of all the valid pixels when the photosensitive surface is applied with the light
of uniform illumination. This is calculated by the following formula.

X) and storage time (s) when saturation of output voltage occurs.

µ

PD3794

PRNU (%) =

∆x

× 100

x

∆x : maximum of x

x =
x

OUT

V

Register Dark

DC level

j − x 

2700

xj

Σ

j=1

2700

j : Output voltage of valid pixel number j

∆x

x

4. Average dark signal: ADS
Average output signal voltage of all the valid pixels at light shielding. This is calculated by the following formula.

2700

d

j

Σ

ADS (mV) =

j=1

2700

j

: Dark signal of valid pixel number j

d

5. Dark signal non-uniformity: DSNU
Absolute maximum of the difference between ADS and voltage of the highest or lowest output pixel of all the valid
pixels at light shielding. This is calculated by the following formula.

DSNU (mV) : maximum of d

− ADS 

j = 1 to 2700

j

dj : Dark signal of valid pixel number j

V

OUT

ADS

Register Dark

DC level

DSNU

12

6. Output impedance: ZO
Impedance of the output pins viewed from outside.

7. Response: R
Output voltage divided by exposure (Ix•s).
Note that the response varies with a light source (spectral characteristic).

8. Image Lag: IL
The rate between the last output voltage and the next one after read out the data of a line.

φ

TG

µ

PD3794

Light

V

OUT

ON OFF

V

OUT

V

1

V1
IL (%) = ×100

V

OUT

9. Random noise: σ
Random noise σ is defined as the standard deviation of a valid pixel output signal with 100 times (=100 lines)
data sampling at dark (light shielding).

100

(Vi – V)

σ (mV) = , V =

Σ

i=1

2

100

i: A valid pixel output signal among all of the valid pixels for each color

V

OUT

1

100

100

Σ

i=1

V

i

V

1

V

2

…

line 1V

line 2

…

V

100

line 100

This is measured by the DC level sampling of only the signal level, not by CDS (Correlated Double Sampling).

13

STANDARD CHARACTERISTIC CURVES

g

DARK OUTPUT TEMPERATURE

CHARACTERISTIC

8

4

2

1

0.5

Relative Output Voltage

0.25

STORAGE TIME OUTPUT VOLTAGE

CHARACTERISTIC (T

2

1

Relative Output Voltage

0.2

A = +25 °C)

µ

PD3794

0.1
100 20304050

Operatin

100

80

60

40

Response Ratio (%)

20

Ambient Temperature TA(°C) Storage Time (ms)

0.1
1510

TOTAL SPECTRAL RESPONSE CHARACTERISTICS

(without infrared cut filter) (T

R

B

G

A

= +25 °C)

G

14

0

400

500 600

Wavelength (nm)

B

700 800

APPLICATION CIRCUIT EXAMPLE

VOUT

PD3794

µ

NC

GND

NC

NC

NC

NC

NC

NC

NC

GND

NC

GND

φ

TG3

φ

φ

2

φ

TG1

φ

1

φ

TG2

47 Ω

4.7 Ω

10 Ω

10 Ω

4.7 Ω

10 Ω

122

21

20

19

18

17

16

15

14

13

12

2

3

4

5

6

7

8

9

10

11

B

SEL1

SEL2

V

OD

φ

RB

+12 V

10 Ω

µ

0.1 Fµ47 F/25 V
SEL1

SEL2

µ

0.1 F

µ

10 F/16 V

TG

1

φ

φ

RB

φ

+

+5 V

+5 V

+

2

47 Ω

47 Ω

µ

0.1 Fµ10 F/16 V

+

µ

PD3794

Remark Inverters: 74HC04

OUT

B EQUIVALENT CIRCUIT

CCD
V

100 Ω

100 Ω

12 V

+

µ

47 F/25 V

2SC945

2 kΩ

15

PACKAGE DRAWING

CCD LINEAR IMAGE SENSOR 22PIN PLASTIC DIP (400 mil)

(Unit : mm)

1st valid pixel

µ

PD3794

3.95±0.3

1.02±0.15

0.46±0.1

3

37.5

44.0±0.3

25.4

2.54

(5.42)

4.21±0.5

2.0

9.25±0.3

4.39±0.4

0~10°

(1.99)

10.16

2.35±0.2

0.25±0.05

1

16

Name Dimensions

Plastic cap

1 The bottom of the package The surface of the chip
2 The thickness of the cap over the chip
3 The 1st valid pixel The center of the pin 1.

42.9 x 8.35 x 0.7

Refractive index

2

22C-1CCD-PKG10-1

1.5

µ

PD3794

RECOMMENDED SOLDERING CONDITIONS

When soldering this product, it is highly recommended to observe the conditions as shown below.
If other soldering processes are used, or if the soldering is performed under different conditions, please make sure

to consult with our sales offices.

For more details, refer to our document "Semiconductor Device Mounting Technology Manual"(C10535E).

Type of Through-hole Device

µ

PD3794CY: CCD linear image sensor 22-pin plastic DIP (400 mil)

Process

Partial heating method

Caution During assembly care should be taken to prevent solder or flux from contacting the plastic cap.

The optical characteristics could be degraded by such contact.

Pin temperature: 260 °C or below,
Heat Time: 10 seconds or less (per pin)

Conditions

17

NOTES ON CLEANING THE PLASTIC CAP

1 CLEANING THE PLASTIC CAP

Care should be taken when cleaning the surface to prevent scratches.
The optical characteristics of the CCD will be degraded if the cap is scratched during
cleaning.

We recommend cleaning the cap with a soft cloth moistened with one of the recommended
solvents below. Excessive pressure should not be applied to the cap during cleaning. If the
cap requires multiple cleanings it is recommended that a clean surface or cloth be used.

µ

PD3794

2 RECOMMENDED SOLVENTS

The following are the recommended solvents for cleaning the CCD plastic cap. Use of
solvents other than these could result in optical or physical degradation in the plastic cap.
Please consult your sales office when considering an alternative solvent.

Solvents Symbol

Ethyl Alcohol EtOH
Methyl Alcohol MeOH
Isopropyl Alcohol IPA
N-methyl Pyrrolidone NMP

18

NOTES FOR CMOS DEVICES

1 PRECAUTION AGAINST ESD FOR SEMICONDUCTORS

Note: Strong electric field, when exposed to a MOS device, can cause destruction of

the gate oxide and ultimately degrade the device operation. Steps must be
taken to stop generation of static electricity as much as possible, and quickly
dissipate it once, when it has occurred. Environmental control must be
adequate. When it is dry, humidifier should be used. It is recommended to
avoid using insulators that easily build static electricity. Semiconductor
devices must be stored and transported in an anti-static container, static
shielding bag or conductive material. All test and measurement tools including
work bench and floor should be grounded. The operator should be grounded
using wrist strap. Semiconductor devices must not be touched with bare
hands. Similar precautions need to be taken for PW boards with semiconductor
devices on it.

µ

PD3794

2 HANDLING OF UNUSED INPUT PINS FOR CMOS

Note: No connection for CMOS device inputs can be cause of malfunction. If no

connection is provided to the input pins, it is possible that an internal input
level may be generated due to noise, etc., hence causing malfunction. CMOS
device behave differently than Bipolar or NMOS devices. Input levels of CMOS
devices must be fixed high or low by using a pull-up or pull-down circuitry. Each
unused pin should be connected to VDD or GND with a resistor, if it is considered
to have a possibility of being an output pin. All handling related to the unused
pins must be judged device by device and related specifications governing the
devices.

3 STATUS BEFORE INITIALIZATION OF MOS DEVICES

Note: Power-on does not necessarily define initial status of MOS device. Production

process of MOS does not define the initial operation status of the device.
Immediately after the power source is turned ON, the devices with reset function
have not yet been initialized. Hence, power-on does not guarantee out-pin
levels, I/O settings or contents of registers. Device is not initialized until the
reset signal is received. Reset operation must be executed immediately after
power-on for devices having reset function.

19

µ

PD3794

[MEMO]

The application circuits and their parameters are for reference only and are not intended for use in actual design-ins.

No part of this document may be copied or reproduced in any form or by any means without the prior written
consent of NEC Corporation. NEC Corporation assumes no responsibility for any errors which may appear in
this document.
NEC Corporation does not assume any liability for infringement of patents, copyrights or other intellectual property
rights of third parties by or arising from use of a device described herein or any other liability arising from use
of such device. No license, either express, implied or otherwise, is granted under any patents, copyrights or other
intellectual property rights of NEC Corporation or others.
While NEC Corporation has been making continuous effort to enhance the reliability of its semiconductor devices,
the possibility of defects cannot be eliminated entirely. To minimize risks of damage or injury to persons or
property arising from a defect in an NEC semiconductor device, customers must incorporate sufficient safety
measures in its design, such as redundancy, fire-containment, and anti-failure features.
NEC devices are classified into the following three quality grades:
"Standard", "Special", and "Specific". The Specific quality grade applies only to devices developed based on a
customer designated "quality assurance program" for a specific application. The recommended applications of
a device depend on its quality grade, as indicated below. Customers must check the quality grade of each device
before using it in a particular application.

Standard: Computers, office equipment, communications equipment, test and measurement equipment,

audio and visual equipment, home electronic appliances, machine tools, personal electronic
equipment and industrial robots

Special: Transportation equipment (automobiles, trains, ships, etc.), traffic control systems, anti-disaster

systems, anti-crime systems, safety equipment and medical equipment (not specifically designed
for life support)

Specific: Aircrafts, aerospace equipment, submersible repeaters, nuclear reactor control systems, life

support systems or medical equipment for life support, etc.
The quality grade of NEC devices is "Standard" unless otherwise specified in NEC's Data Sheets or Data Books.
If customers intend to use NEC devices for applications other than those specified for Standard quality grade,
they should contact an NEC sales representative in advance.
Anti-radioactive design is not implemented in this product.

M4 96.5