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 SN28846

 SERIAL DRIVER

 

 SOCS024B – FEBRUARY 1991

Copyright 

©

 1991, Texas Instruments Incorporated

 1

POST OFFICE BOX 655303 

 DALLAS, TEXAS 75265

TTL-Compatible Inputs

CCD-Compatible Outputs

Full-Frame Operation

Frame-Transfer Operation

Solid-State Reliability

Adjustable Clock Levels

     

description

The SN28846 serial driver is a monolithic CMOS

integrated circuit designed to drive the serial-reg-

ister gate (SRGn) and transfer-gate (TRG) inputs

of the Texas Instruments (TI

) virtual-phase CCD

image sensors. The SN28846 interfaces a

user-defined timing generator to the CCD image

sensor; it receives TTL signals from the timing generator and outputs level-shifted signals to the image sensor.

The SN28846 contains three noninverting serial-gate drivers and one noninverting transfer-gate driver.

The voltage levels on SRG1OUT, SRG2OUT, SRG3OUT, and TRGOUT are controlled by the levels on V

SS

 and

V

CC

. The propagation delays for these outputs are controlled  by SEL0 and SEL1. The PD, SRG1IN, SRG2IN,

SRG3IN, and TRGIN are TTL compatible.

A high level on PD allows the SN28846 to operate normally with the level-shifted outputs following the inputs.

When PD is low, the device is in a low power-consumption mode and all outputs are at V

CC

.

The SN28846 is available in a 20-pin surface-mount package and is characterized for operation from –20

°

C

to 45

°

C.

This device contains circuits to protect its inputs and outputs against damage due to high static voltages or electrostatic fields. These

circuits have been qualified to protect this device against electrostatic discharges (ESD) of up to 2 kV according to MIL-STD-883C,

Method 3015; however, precautions should be taken to avoid application of any voltage higher than maximum-rated voltages to these

high-impedance circuits. 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 an appropriated logic voltage level, preferably either VCC or ground.

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.

TI is a trademark of Texas Instruments Incorporated.

1

2

3

5

6

7

8

9

10

20

19

18

17

16

15

14

13

12

11

SEL0OUT

GND

PD

SRG3IN

SRG2IN

SRG1IN

TRGIN

NC

SEL1OUT

V

SS

V

SS

SEL0

NC

V

CC

SRG3OUT

SRG2OUT

SRG1OUT

TRGOUT

V

CC

SEL1

DW 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.

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SN28846

SERIAL DRIVER

 

SOCS024B – FEBRUARY 1991

 2

POST OFFICE BOX 655303 

 DALLAS, TEXAS 75265

logic symbol

6

19

14

3

5

7

15

16

13

11

4

SEL0

SEL1

PD

SRG1IN

SRG2IN

SRG3IN

TRGIN

SRG1OUT

SRG2OUT

SRG3OUT

TRGOUT

Φ

† This symbol is in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.

Terminal Functions

TERMINAL

I/O

DESCRIPTION

NAME

NO.

I/O

DESCRIPTION

GND

2

Ground

NC‡

8

No connect

NC‡

18

No connect

PD

3

I

Power down

SEL0

19

I

Propagation delay mode select

SEL1

11

I

Propagation delay mode select

SEL0OUT

1

O

Test pin (factory use only)

SEL1OUT

9

O

Test pin (factory use only)

SRG1IN

6

I

Serial-register gate 1 in

SRG2IN

5

I

Serial-register gate 2 in

SRG3IN

4

I

Serial-register gate 3 in

SRG1OUT

14

O

Serial-register gate 1 out

SRG2OUT

15

O

Serial-register gate 2 out

SRG3OUT

16

O

Serial-register gate 3 out

TRGIN

7

I

Transfer gate in

TRGOUT

13

O

Transfer gate out

VCC‡

12

I

Positive supply voltage

VCC‡

17

I

Positive supply voltage

VSS‡

10

I

Negative supply voltage

VSS‡

20

I

Negative supply voltage

‡ All terminals of the same name should be connected together externally.

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 SN28846

 SERIAL DRIVER

 

 SOCS024B – FEBRUARY 1991

 3

POST OFFICE BOX 655303 

 DALLAS, TEXAS 75265

absolute maximum ratings over operating free-air temperature range (unless otherwise noted)

Positive supply voltage, V

CC

 (see Note 1) 

 4 V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Negative supply voltage, V

SS

 (see Note 2) 

 –11.1 V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Input voltage range: SEL0 and SEL1 

 V

SS

 to V

CC

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Other inputs 

 0 to 5.5 V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Continuous total power dissipation at (or below) T

A

 

 25

°

C: Unmounted device (see Figure 1) 

 825 mW

. . . 

Mounted device (see Figure 1) 

 1150 mW

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

. . . . . 

Operating free-air temperature range, T

A

   

– 20

°

C to 45

°

C

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Storage temperature range, T

STG

   

– 55

°

C to 125

°

C

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds 

 260

°

C

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

† Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and

functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not

implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

NOTES:

1. All voltage values are with respect to the GND terminal.

2. The algebraic convention, in which the least positive (most negative) value is designated minimum, is used in this data sheet for

voltage levels only.

0

10

20

30

40

50

60

70

0

500

1000

1500

P

D

– Power Dissipation – mW

TA – Free-Air Temperature – 

°

C

Mounted Device

(see Note A)

Unmounted Device

POWER DISSIPATION

vs

FREE-AIR TEMPERATURE

100

200

300

400

600

700

800

900

1100

1200

1300

1400

Figure 1

NOTE A: The mounted-device derating curve of Figure 1 is obtained under the following conditions:

The board is 50 mm by 50 mm by 1.6 mm thick.

The board material is glass epoxy.

The copper thickness of all the etch runs is 35 microns.

Etch run dimensions – All 20 etch runs are 0.4 mm by 22 mm.

Each chip is soldered to the board.

An aluminum cooling fin 10 mm by 10 mm by 1 mm thick is coupled to the chip with thermal paste.

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SN28846

SERIAL DRIVER

 

SOCS024B – FEBRUARY 1991

 4

POST OFFICE BOX 655303 

 DALLAS, TEXAS 75265

recommended operating conditions

MIN

NOM

MAX

UNIT

Positive supply voltage, VCC

0

1.5

3

V

Negative supply voltage, VSS (see Note 2)

–11.1

–10.4

–9.7

V

SRG1IN, SRG2IN, SRG3IN, TRGIN

2

5

High-level input voltage, VIH

SEL0, SEL1

VCC

V

PD

4

5

SRG1IN, SRG2IN, SRG3IN, TRGIN

0

0.8

Low-level input voltage, VIL

SEL0, SEL1

VSS

V

PD

0

0.4

Capacitance load

SRG1OUT, SRG2OUT, SRG3OUT

200

pF

Capacitance load

TRGOUT

350

pF

Operating free-air temperature, TA

– 20

45

°

C

NOTE 2: The algebraic convention, in which the least positive (most negative) value is designated minimum, is used in this data sheet for voltage

levels only.

electrical characteristics over recommended ranges of supply voltage and operating free-air

temperature (unless otherwise noted)

PARAMETER

TEST CONDITIONS

MIN

MAX

UNIT

VOH

High-level output voltage

SRG1OUT, SRG2OUT,

SRG3OUT

f = 4.8 MHz,

See Figure 2

tw = 70 ns,

VCC – 0 5

VCC+0 5

V

VOH

High-level out ut voltage

TRGOUT

f = 3.6 MHz,

See Figure 2

tw = 140 ns,

VCC – 0.5

VCC+0.5

V

VOL

Low-level output voltage

SRG1OUT, SRG2OUT,

SRG3OUT

f = 4.8 MHz,

See Figure 2

tw = 70 ns,

VSS – 0 8

VSS+0 8

V

VOL

Low-level out ut voltage

TRGOUT

f = 3.6 MHz,

See Figure 2

tw = 140 ns,

VSS – 0.8

VSS+0.8

V

VN(PP)

Peak-to-peak output

noise voltage

SRG1OUT, SRG2OUT,

SRG3OUT

See Figure 2

300

mV

IIH

High-level input current

SRG1IN, SRG2IN,

SRG3IN, TRGIN,

SEL0, SEL1

VI = 5.5 V

50

µ

A

IIL

Low-level input current

VI = 0

±

10

µ

A

ISS

Supply current

No load, PD at 0 V, TA = 25

°

C

– 0.5

mA

ISS

Supply current

See Note 3

–25

mA

fmax

Maximum frequency

of oscillation

SRG1OUT, SRG2OUT,

SRG3OUT

CL = 200 pF

10

MHz

max

of oscillation

TRGOUT

CL = 350 pF

1

NOTE 3: SRG1OUT, SRG2OUT, and SRG3OUT are loaded with 80-pF capacitive loads; TRGOUT is loaded with a 180-pF load. The SN28846

driver is clocked by the SN28835 timer. SEL0 and SEL1 are both held at –11.1 V.

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 SN28846

 SERIAL DRIVER

 

 SOCS024B – FEBRUARY 1991

 5

POST OFFICE BOX 655303 

 DALLAS, TEXAS 75265

switching characteristics for SRG1OUT, SRG2OUT, and SRG3OUT, V

CC

 = 2.3 V, V

SS

 = – 10.3 V, 

T

A

 = 25

°

C (unless otherwise noted) (see Figure 2)

PARAMETER

SELECT

MODE ‡

TEST CONDITIONS

MIN

TYP

MAX

UNIT

0

28

tPLH

Propagation delay time,

1

t

= 70 ns

f = 4 8 MHz

36

ns

tPLH

g

y

low-to-high-level output

2

tw = 70 ns,

f = 4.8 MHz

42

ns

3

48

0

25

tPHL

Propagation delay time,

1

t

= 70 ns

f = 4 8 MHz

24

ns

tPHL

g

y

high-to-low-level output

2

tw = 70 ns,

f = 4.8 MHz

23

ns

3

23

tPLH

(see Note 4)

±

5

tPHL

(see Note 4)

Any

TA = 20

°

C to 55

°

C

±

5

ns

t k( )

Skew time (see Note 5)

Any

TA = – 20

°

C to 55

°

C

5

ns

tsk(o)

Skew time (see Note 5)

5

0

63

68

73

t

Pulse duration

1

t

= 70 ns

f = 4 8 MHz

54

59

64

ns

tw

Pulse duration

2

tw = 70 ns,

f = 4.8 MHz

47

52

57

ns

3

40

45

50

tw(n) – tw(m)

Pulse duration differential

(see Note 6)

Any

tw = 70 ns,

f = 4.8 MHz

5

ns

tr

Rise time

Any

t

= 70 ns

f = 4 8 MHz

10

14

18

ns

tf

Fall time

Any

tw = 70 ns,

f = 4.8 MHz

6

10

13

ns

† The load is a Texas Instruments CCD image sensor.

‡ The select mode is determined by the voltage levels applied to the SEL1 and SEL0 inputs as follows:

SELECT MODE

SEL1

SEL0

0

VSS

VSS

1

VSS

VCC

2

VCC

VSS

3

VCC

VCC

NOTES:

4. For a given channel, 

tPLH and 

tPHL are the changes in tPLH and tPHL, respectively, when the device is operated over the

temperature range – 20

°

C to 55

°

C rather than at 25

°

C.

5. This is the maximum absolute difference in propagation delay time, either tPLH or tPHL, through the three channels at any given

temperature within the specified range.

6. This is the maximum difference in the pulse duration through the three channels.

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SN28846

SERIAL DRIVER

 

SOCS024B – FEBRUARY 1991

 6

POST OFFICE BOX 655303 

 DALLAS, TEXAS 75265

switching characteristics for TRGOUT, V

CC

 = 2.3 V, V

SS

 = –10.3 V, T

A

 = 25

°

C (unless otherwise noted)

(see Figure 2)

PARAMETER

SELECT

MODE ‡

TEST CONDITIONS

MIN

TYP

MAX

UNIT

0

24

tPLH

Propagation delay time,

1

t

= 140 ns

f = 3 6 MHz

33

ns

tPLH

g

y

low-to-high-level output

2

tw = 140 ns,

f = 3.6 MHz

39

ns

3

47

0

24

tPHL

Propagation delay time,

1

t

= 140 ns

f = 3 6 MHz

23

ns

tPHL

g

y

high-to-low-level output

2

tw = 140 ns,

f = 3.6 MHz

22

ns

3

22

tPLH

(see Note 7)

Any

TA = 20

°

C to 55

°

C

20

ns

tPHL

(see Note 7)

Any

TA = – 20

°

C to 55

°

C

20

ns

tw

Pulse duration

100

140

180

tr

Rise time

Any

tw = 140 ns,

f = 3.6 MHz

17

ns

tf

Fall time

10

† The load is a Texas Instruments CCD image sensor.

‡ The select mode is determined by the voltage levels applied to SEL1 and SEL0 as follows:

SELECT MODE

SEL1

SEL0

0

VSS

VSS

1

VSS

VCC

2

VCC

VSS

3

VCC

VCC

NOTE 7:

tPLH and 

tPHL are the changes in tPLH and tPHL, respectively, when the device is operated over the temperature range – 20

°

C to 55

°

C

rather than at 25

°

C.

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 SN28846

 SERIAL DRIVER

 

 SOCS024B – FEBRUARY 1991

 7

POST OFFICE BOX 655303 

 DALLAS, TEXAS 75265

PARAMETER MEASUREMENT INFORMATION

50%

50%

10%

90%

10%

90%

0% + 2 V

100% – 2 V

tf

tr

tPLH

tPHL

SRG1OUT, SRG2OUT,

SRG3OUT, or TRGOUT

SRG1IN, SRG2IN,

SRG3IN, or TRGIN

SRG1OUT, SRG2OUT,

SRG3OUT, or TRGOUT

SRG1OUT, SRG2OUT,

or SRG3OUT

SRG1OUT, SRG2OUT,

or SRG3OUT

VCC + 0.5 V

VCC

VCC – 0.5 V

(worst case)

VSS + 0.8 V

VSS – 0.6 V

VSS

VSS + 0.15 V

VSS – 0.15 V

tw

PULSE DURATION AND RISE AND FALL TIMES

PROPAGATION DELAYS

SRG1OUT, SRG2OUT,

or SRG3OUT

SRG1OUT, SRG2OUT,

or SRG3OUT

VCC + 0.5 V

VCC

VCC – 0.5 V

(typical)

VSS + 0.8 V

VSS + 0.15 V

VSS – 0.15 V

VSS – 0.6 V

VSS

TYPICAL AND WORST-CASE OUTPUT NOISE

51 

CL = 80 pF

(see Note A)

From Output

Under Test

NOTE A: CL Includes probe and jig capacitance.

Figure 2. Load Circuit and Voltage Waveforms

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SN28846

SERIAL DRIVER

 

SOCS024B – FEBRUARY 1991

 8

POST OFFICE BOX 655303 

 DALLAS, TEXAS 75265

MECHANICAL DATA

DW/R-PDSO-G**

PLASTIC WIDE-BODY SMALL-OUTLINE PACKAGE

20 PIN SHOWN

0.419 (10,65)

0.400 (10,15)

0.293 (7,45)

0.299 (7,59)

0.093 (2,35)

0.104 (2,65)

0.012 (0,30)

0.004 (0,10)

0.009 (0,23)

0.012 (0,30)

0.050 (1,27)

0.016 (0,40)

0.020 (0,51)

0.014 (0,35)

16

0.400

(10,16)

A  MIN

A  MAX

(10,41)

0.410

0.510

(12,95)

(12,70)

0.500

20

0.610

(15,49)

(15,24)

0.600

24

0.710

(18,03)

(17,78)

0.700

28

DIM

 PINS**

4040000/A–10/93

20

11

1

10

0.338 (8,58)

0.364 (9,24)

A

Seating Plane

0.004 (0,10)

0

°

– 8

°

M

0.010 (0,25)

0.050 (1,27)

NOTES: A. All linear dimensions are in inches (millimeters).

B. This drawing is subject to change without notice.

C. Body dimensions do not include mold flash or protrusion not to exceed 0.006 (0,15).

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Texas Instruments and its subsidiaries (TI) reserve the right to make changes to their products or to discontinue

any product or service without notice, and advise customers to obtain the latest version of relevant information

to verify, before placing orders, that information being relied on is current and complete. All products are sold

subject to the terms and conditions of sale supplied at the time of order acknowledgement, including those

pertaining to warranty, patent infringement, and limitation of liability.

TI warrants performance of its semiconductor products to the specifications applicable at the time of sale in

accordance with TI’s standard warranty. Testing and other quality control techniques are utilized to the extent

TI deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily

performed, except those mandated by government requirements.

CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF

DEATH, PERSONAL INJURY, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE (“CRITICAL

APPLICATIONS”). TI SEMICONDUCTOR PRODUCTS ARE NOT DESIGNED, AUTHORIZED, OR

WARRANTED TO BE SUITABLE FOR USE IN LIFE-SUPPORT DEVICES OR SYSTEMS OR OTHER

CRITICAL APPLICATIONS. INCLUSION OF TI PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD TO

BE FULLY AT THE CUSTOMER’S RISK.

In order to minimize risks associated with the customer’s applications, adequate design and operating

safeguards must be provided by the customer to minimize inherent or procedural hazards.

TI assumes no liability for applications assistance or customer product design. TI does not warrant or represent

that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other

intellectual property right of TI covering or relating to any combination, machine, or process in which such

semiconductor products or services might be or are used. TI’s publication of information regarding any third

party’s products or services does not constitute TI’s approval, warranty or endorsement thereof.

Copyright 

©

 1998, Texas Instruments Incorporated