background image

T

V

DD

V

IN

CAP1–

CAP2–

CAP1+

CAP2+

OSC1

OSC2

CR

Oscillator

Voltage

Converter

 (I)

Voltage

Converter

 (II)

Reference Voltage

Generator

Voltage Regulator

Temperature Gradient

Select Circuit

TC1

TC2

P

off

V

reg

V

out

RV

Booster

Regurator

DC-DC Converter

PF110-10

q

 95% Typical Power Efficiency

Doubled or Tripled Output Voltage

Internal Voltage Regulator

SCI7661C

OA

/M

OA

DESCRIPTION

The SCI7661C

OA

/M

OA

CMOS DC-DC Converter features high operational performance with low power dissipation.

It consists of two major parts: the booster circuitry and the regulator circuitry. The booster generates a doubled

output voltage

  (–2.4 to –12V) or tripled output voltage

  (–3.6 to –18V) from the input

   (–1.2 to –6V). The regulator is

capable of setting the output to any desired voltage. The regulated voltage can be given one of the three threshold

temperature gradients.

FEATURES

High performance with low power dissipation

Simple conversion of V

IN

   

(–5V) to |V

IN

|  (+5V),

2 |V

IN

|  (+10V), 2V

IN

   

(–10V) or 3V

IN

  

(–15V)

On-chip output voltage regulator

Power conversion efficiency–Typ. 95%

q

 Temperature gradient for LCD power supply – 0.1% / 

°

C, 0.4%/

°

C or 0.6%/ 

°

C

Power off by external signals – Stationary current at power off – Max. 2 

µ

A

Cascade connection–two device connected:

V

IN

=–5V, V

OUT

=–20V

On-chip C'–R oscillator

Package .................................... SCI7661C

0A

: DIP-14pin

  (plastic)

SCI7661M

0A

: SOP5-14pin

  (plastic)

SCI7661M

AA

: SSOP2-16pin

  (plastic)

BLOCK DIAGRAM

Low Voltage

Operation

Products

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2

SCI7661C

OA

/M

OA

s

 PIN CONFIGURATION

   s 

PIN DESCRIPTION

ELECTRICAL CHARACTERISTICS

ABSOLUTE MAXIMUM RATINGS

CAP1+

CAP2+

CAP1-

CAP2-

TC1

TC2

V

IN

1

3

2

4

5

6

7

V

DD

P

off

V

reg

V

out

OSC1

OSC2

RV

14

11

9

8

13

12

10

The same pin configuration in

DIP and SOP

CAP1+, CAP1-

CAP2+, CAP2-

TC1, TC2

V

IN

V

OUT

Vreg

R

V

P

off

OSC2, OSC1

V

DD

1, 2

3, 4

5, 6

7

8

9

10

11

12, 13

14

Pin name

No.

Function

Terminal for connection of capacitor for doubler

Terminal for connection of capacitor for tripler

Temperature gradient selection terminal

Power supply terminal(negative, system supply 

GND)

Output terminal at tripling

Regulated voltage output terminal

Regulated voltage control terminal

Vreg output ON/OFF control terminal

Oscillation resistor connection terminal

Power supply terminal(positive system supply 

VCC)

Characteristic

Symbol

Condition

Min.

Typ.

Max.

Unit

(V

DD

 = 0V, V

IN

=-5V, Ta=-30 to 85

°

C)

V

reg

V

OUT

•V

reg

R

L

=

, R

RV

=1M

V

O

=-18V

R

L

=

, R

OSC

=1M

R

L

=

, R

RV

=1M

V

OUT

=-15V

-18V<V

OUT

<-8V, 

V

reg

=-8V, R

L

=

, Ta=25

°

C

TC2=TC1=V

OUT

, R

L

=

R

OSC

=1M

I

OUT

=10mA

V

I

V

O

-6.0

-18.0

-1.2

V

V

V

OUT

Iopr

1

-18.0

60

50

20

150

-3.2

100

V

µ

A

-18

Vreg

-2.6

V

Iopr

2

12.0

µ

A

I

OUT

=5mA

95

Peff

%

0.2

%/V

I

Q

f

osc

R

OUT

16

90

2.0

24

200

µ

A

kHz

Input supply voltage

Output voltage

Regulator operating voltage

Booster current consumption

Regulator current

consumption

Booster power conversion

efficiency

Regulated output voltage

fluctuation

Stationary current

Oscillation frequency

Output impedance

V

I

Input terminal voltage

OSC1, P

off

TC1, TC2, RV

Plastic package

Rating

Symbol

Remark

V

V

Unit

0.5

0.5

Max.

V

IN

-0.5

V

OUT

-0.5

V

O

P

d

T

opr

T

stg

T

sol

Output voltage

Allowable loss

Operating temperature

Storage temperature

Soldering temperature and time

V

mW

°

C

°

C

-

300

85

150

-20.0

-30

-55

V

I

Input supply voltage

V

0.5

-20/N

Min.

(V

DD

=0V)

260

°

C, 10s(at lead)

N

=

2 : Doubler

N

=

3 : Tripler

Note: When this IC is soldered in the solder-reflow process, be sure to maintain the reflow furnace at the curve shown in "Fig.

1-5 Reflow Furnace Temperature Curve"  of this DATA BOOK. And this IC can not be exposed to high temperature of

the solder dipping.

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3

SCI7661C

OA

/M

OA

RECOMMENDED OPERATING CONDITIONS

(V

IN=

-

1.2V ~ 

-

2.2V)

=C

1

=10

µ

F

C

2

=10

µ

F

+

-

+

+ -

-

1

2

3

4

5

6

7

14

13

12

11

10

9

8

R

OSC

=

1M

R

L

C

L

C

3

=22

µ

F

D

1

(

V

F

(

I

F

=1mA

)) 

 

0.6v

5

4

3

2

1

0

0

1.5 2

3

4 5 6

V

STA2

V

STA1

V

IN

(

V)

Triple

Double

R

L

 Min.

(

k

)

Characteristic

Symbol

Condition

Min.

Typ.

Max.

Unit

V

reg

I

OUT

| V

reg

(50

°

C) | - | V

reg

(0

°

C) |

50

°

C-0

°

C

CT = 

1

| V

reg

(25

°

C) |

×

×

100

V

OUT

=-15V, V

reg

=-8V,

Ta=25

°

C

0<I

OUT

<10mA, TC1=V

DD

TC2=V

OUT

R

SAT

=D(Vreg—V

OUT

)/DI

OUT

0<I

OUT

<10mA, RV=V

DD

,

Ta=25

°

C

TC2=V

OUT

, TC1=V

DD

, Ta=25

°

C

TC2=TC1=V

OUT

, Ta=25

C

P

off

, TC1, TC2, OSC1, RV pins

5

5

R

SAT

V

V

V

-1.5

-1.3

-0.9

-1.0

-1.1

-0.8

-2.3

-1.7

-1.1

V

RV0

V

RV1

V

RV2

%/

°

C

%/

°

C

%/

°

C

-0.1

-0.4

-0.6

-0.06

-0.3

-0.5

-0.25

-0.5

-0.7

CT

0

CT

4

CT

2

µ

A

2.0

I

L

Regulated output load

fluctuation

Regulated output saturation

resistance

Reference voltage

Temperature Gradient

Input leakage current

TC2=V

DD

, TC1=V

OUT

, Ta=25

°

C

Condition

Symbol

Remark

Unit

Max.

Min.

(Ta=-30 to 85

°

C)

R

OSC

=1M

, C

3

10

µ

F*

1

C

L

/C

3

1/20, Ta=-20 to 85

°

C

R

OSC

=1M

R

OSC

=1M

V

V

V

mA

kHz

-2.2

2000

-1.2

20

30

-1.2

R

L

 Min.*

2

10

V

STA2

V

STA1

V

STP

R

L

I

OUT

f

OSC

Booster start voltage

Booster stop voltage

Output load resistance

Output load current

Oscillation frequency

µ

F

3.3

C

1

, C

2

, C

3

k

680

R

OSC

Capasitor for booster

Extarnal resistance for

oscillation

1000

k

100

R

RV

Regulated output adjustable

resistance

*1: Recommended circuity in low voltage operation is

shown below.

*2: R

L

 Min. depends on input voltage as shown below.

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4

SCI7661C

OA

/M

OA

PERFORMANCE CURVES

f

OSC

(kHz)

I

opr1

(

µ

A)

f

OSC

(kHz)

P

eff

(%)

P

eff

(%)

V

reg

(V)

I

IN

(mA)

I

IN

(mA)

P

eff

(%)

P

eff

(%)

V

OUT

(V)

R

OUT

(

)

R

OSC

(

)

I

OUT

(mA)

I

OUT

(mA)

I

OUT

(mA)

f

OSC

(Hz)

I

OUT

(mA)

V

IN

(V)

1000

V

OUT

(V)

0

100

90

80

70

60

50

40

30

20

10

0

100

90

80

70

60

50

40

30

20

10

0

100

90

80

70

60

50

40

30

20

10

0

100

90

80

70

60

50

40

30

20

10

0

100

90

80

70

60

50

40

30

20

10

0

40

36

32

28

24

20

16

12

8

4

0

-5

0

400

300

200

100

0

0

1

2

3

4

5

6

7

-1

-2

-3

-4

-5

-6

-10

-15

26

25

24

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9

8

100

10

1

20

30

10K

–30

0

0

0

10

0

10

3

10

4

10

5

10

6

f

OSC

(Hz)

I

OUT

(A)

10

3

10

-4

10

-3

10

-2

10

-1

I

OUT

(A)

10

-4

10

-3

10

-2

10

-1

10

4

10

5

10

6

1

3

5

7

9

2

4

6

8

10

20

30

40

50

0

1

2

3

4

5

6

7

8

9

10

10

20

30

40

50

50

100

150

0

1

2

3

4

5

6

7

100K

680K1M

10M

V

IN

=-5V

V

IN

=-5V

V

IN

=-5V

V

IN

=-3V

V

IN

=-3V

V

IN

=-1.5V

V

IN

=-1.5V

V

IN

(V)

150

100

50

Ta=25

°

C

Ta=25

°

C

V

IN

=-5.0V

Ta=25

°

C

V

IN

=-2.0V

Ta=25

°

C

V

OUT

=-15V

Ta=25

°

C

V

OUT

=-6V

Ta=25

°

C

V

IN

=-5V

Ta=25

°

C

Ta=25

°

C

f

OSC

=40kHz

f

OSC

=20kHz

f

OSC

=10kHz

Ta(

°

C)

Fig.1  Oscillation Frequency(f

OSC

)vs.

          External-Resistance(R

OSC

)

Fig.4  Output Voltage(V

OUT

)vs.

          Output Current(I

OUT

)

Fig.7  Power Conversion Efficiency

        (P

eff

)/Input Current(I

IN

)vs.

          Output Current(I

OUT

)

Fig.10  Power Conversion Efficiency(P

eff

)

            vs.Oscillation Frequency(f

OSC

)

Fig.11  Output Voltage(V

reg

)vs. Output

            Current(I

OUT

)

Fig.12  Output Voltage(V

reg

)vs. Output

            Current(I

OUT

)

Fig.8  Power Conversion Efficiency

        (P

eff

)/Input Current(I

IN

)vs.

          Output Current(I

OUT

)

Fig.9  Power Conversion Efficiency

        (P

eff

)vs. Oscillation Frequency

        (f

OSC

)

Fig.5  Output Voltage(V

OUT

)vs.

          Output Current(I

OUT

)

Fig.6  Output Inpedance(R

OUT

)vs.

          Input Voltage(V

IN

)

Fig.2  Oscillation Frequency(f

OSC

)vs.

          Temperature(Ta)

Fig.3  Input Voltage(V

IN

)vs. Booster

          Current Consumption(I

opr1

)

Double

Double

P

eff

Double P

eff

Double I

IN

Double I

IN

Double

Double

Triple

Triple P

eff

Triple P

eff

Triple

Triple

Triple

I

IN

Triple I

IN

V

IN

=-5.0V

V

IN

=-1.5V

I

OUT

=10mA

I

OUT

=4mA

I

OUT

=20mA

I

OUT

=30mA

I

OUT

=

      5mA

I

OUT

=

      2mA

I

OUT

=

0.5mA

I

OUT

=

   1mA

I

OUT

=

   2mA

-8.000

-7.950

-7.900

-7.850

V

reg

(V)

-3.000

-2.950

-2.900

-2.850

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5

SCI7661C

OA

/M

OA

CIRCUIT DESCRIPTION

C-R Oscillator

The SCI7661C/M contains a C-R oscillator for internal

oscillation. It consists of an external resistor R

OSC

connected between the OSC1 pin and OSC2 pin.

Voltage Converters

The voltage converters doubleÅ^triple the input supply voltage (V

IN

) using clocks generated by the C-R oscillator

q

Reference Voltage Generator and Voltage Regulator

The reference voltage generator produces reference

voltage needed for operation of regulator circuit. The

voltage regulator is used to regulate a boosted output

voltage and its circuit contains a power-off function which

uses signals from the system for on-off control of the

V

reg

 output.

q

 Temperature Gradient Selector Circut

The SCI7661C/M provides the V

reg

 output with a temperature gradient suitable for LCD driving.

0.30

0.25

50

0

-50

0.20

0.15

0.10

0.05

0.00

V

OUT

=

    -5V

V

OUT

=

 -10V

C

T:

-0.1%/

°

C

C

T:

-0.4%/

°

C

C

T:

-0.6%/

°

C

V

OUT

=

    -15V

I

OUT

(mA)

Ta(

°

C)

V

reg

(Ta) | - | V

reg

(25

°

C) |

0

-50

0

50

100

5

10

15

20

V

reg

-V

OUT

(V)

×

100(%)

| V

reg

(25

°

C) |

Fig:13  Regulated Output Saturation

Resistance(R

SAT

)V

reg

—V

OUT

 —I

OUT

Fig:14  Output Voltage(v

reg

)vs.

            Temperature(Ta)

Osc1

Osc2

Osc1

Osc2

R

OSC

C-R Oscillation

External Clock Operation

Open

External Clock

V

CC

V

DD

=0V

V

DD

=0V

V

IN

=-5V

V

IN

=-5V

CAP2=2V

IN

=-10V

V

OUT

=3V

IN

=-15V

(+5V)

(-5V)

GND

Typical Doubled Voltage Relations

Typical Tripled Voltage Relations

V

DD

P

off

V

reg

RV

Voltage Regulator

Control signal

R

RV

 = 100k

 to 1M

background image

6

SCI7661C

OA

/M

OA

5V

V

IN

=-5V

V

OUT

=-15V

C

1

C

2

C

3

10

µ

F

10

µ

F

10

µ

F

1

2

3

4

5

6

7

14

13

12

11

10

9

8

R

OSC

 1M

Voltage Tripler

+

+

+

5V

V

IN

=-5V

V

OUT

=-15V

V

reg

=-8V=

C

1

C

4

R

RV

R

1

RRV

C

2

C

3

10

µ

F

10

µ

F

10

µ

F

10

µ

F

1

2

3

4

5

6

7

14

13

12

11

10

9

8

R

OSC

 

Tripler+Regulator

(-0.4%/

°

C selected as temperature gradient)

+

+

+

1M

100k

~1M

Shield wire

R

1

R

2

V

RV

+

10

µ

F

10

µ

F

+

5V

V

IN

=-5V

V'

OUT

=-20V

V

OUT

=-10V

V'

reg

=-15V

V'

DD

=V

IN

=-15V

1

2

3

4

5

6

7

14

13

12

11

10

9

8

1

2

3

4

5

6

7

14

13

12

11

10

9

8

1M

100k

10

µ

F

+

10

µ

F

+

=V

IN

'

+ −

10

µ

F

+ −

~

1M

10

µ

F

+

Serial Connection

Temperature Gradient Assignment

1(V

DD

)

1

1

1

0(V

IN

)

0

0

0

P

off

L(V

OUT

)

L

H(V

DD

)

H

L

L

H

H

TC2

-0.4%/

°

C

-0.1%/

°

C

-0.6%/

°

C

-0.6%/

°

C

-

-

-

-

Temp. Gradient

ON

ON

ON

ON

OFF(Hi-Z)

OFF(Hi-Z)

OFF(Hi-Z)

OFF(Hi-Z)

V

reg

 Output

ON

ON

ON

OFF

OFF

OFF

OFF

ON

CR oscillation

Cascade connection

Without regulation

Remarks

L(V

OUT

)

H(V

DD

)

L

H

L

H

L

H

TC1

Parallel Connection

5V

V

IN

=-5V

V

OUT

=-15V

Vreg=-10V

C

4

10

µ

F

C

3

10

µ

F

1

2

3

4

5

6

7

14

13

12

11

10

9

8

1

2

3

4

5

6

7

14

13

12

11

10

9

8

R

OSC

 

C

1

C

2

10

µ

F

10

µ

F

+

+

+

C

1

C

2

10

µ

F

10

µ

F

+

+

+

1M

R

OSC

 

1M

100k

~1M

R

RV

BASIC EXTERNAL CONNECTION

Voltage Doubler and Tripler

A doubled voltage can be obtained at V

OUT

 

(CAP2-)

by disconnecting capacitor C

2

 from the tripler

configuration and shorting CAP2-

- (pin4) and V

OUT

(pin 8).

Voltage Tripler+Regulator

V

reg

 output is given a temperature gradient, after

boosted output V

OUT

 regulated. In this connection,

both V

OUT

 and V

reg

 can be taken out  at the same

time.

q

 

Parallel Connection

Parallel connection of n circuits can reduce R

OUT

 to about

1/n, that output impedance R

OUT

 can be reduced by

connecting serial configuraiton. A single smoothing

capacitor C

3

 can be used commonly for all parallely

connected circuit.

In parallely connection, a regulated output can be

obtained by applying the regulation circuit to only one of

the n parallely connected circuit.

Cascade Connection

Cascade connection of SCI7661C/M (by connecting V

IN

 and V

OUT

 of one stage to V

DD

 and V

IN

 respectively of

the next stage) further increase the output voltage. Note, however, that the serial connection increases the

output impedance.

NOTE: The potential at Low level is different between the P

off

 pin and the TC1/TC2 pin.

background image

7

SCI7661C

OA

/M

OA

5V

V

IN

=

  -5V

V

DD

=0V

V

OUT

=8.2V

C

1

10

µ

F

C

2

10

µ

F

C

3

10

µ

F

1

2

3

4

5

6

7

14

13

12

11

10

9

8

ROSC

+ −

+ −

+ −

D

1

D

2

D

3

1M

Positive Voltage Conversion  D1, D2, D3,: Shottky

diodes with small V

F

 are recommended.

5V

V

IN

=

-5V

V

OUT2

=

8.2V

V

DD

=0V

V

OUT1

=-15V

V

OUT1

=-10V

V

OUT2

=13.2V

V

DD

=5V

V

DD

=0V

10

µ

F

10

µ

F

10

µ

F

10

µ

F

1

2

3

4

5

6

7

14

13

12

11

10

9

8

+

+

+

+

+

10

µ

F

+

1M

Negative Voltage Convertion +Positive Voltage Conversion

1

2

3

4

5

6

7

14

13

12

11

10

9

8

10

µ

F

+

R

1

R

RV

R

P

R

T

V

reg

V

DD

Example of Change of Temperature Gradient

Plastic DIP-14pin

Unit: mm

(inch)

14

8

1

7

19.7

max

(

0.775

max

)

19

±

0.1

(

0.748

±

0.003

)

6.3

±

0.1

(

0.248

±

0.003

)

1.5

(

0.059

)

0.46

±

0.1

(

0.018        

)

+0.004

–0.003

2.54

(

0.1

)

0

°

15

°

7.62

(

0.3

)

0.25    

      

(

0.01        

)

+0.001

–0

+0.03

–0.01

0.8

±

0.1

(

0.031        

)

+0.004 –0.003

3

min

(

0.119

min

)

4.4

±

0.1

(

0.173        

)

+0.004 –0.003

PACKAGE DIMENSIONS

q

 Positive Voltage Conversion

The input voltage can be doubled or tripled toward the positive

side. (In the doubler configuration, capacitor C

2

 and diode D

3

are disconnected and the diode D

3

 shorted at the both ends.)

In this case, however, the output voltage decrease by V

F

 (forward

voltage)

For example V

DD

=0V, V

IN

=–5V and V

F

=0.6V, then V

OUT

=10V–

3

×

0.6V=8.2 V (if doubled, 5V–2

×

0.6V=3.8V)

q

 Negative Voltage Conversion + Positive

Voltage Conversion

This circuit produces outputs of –15V and +8.2V from

the –5V input. Note that this configuration causes

higher output impedance than in a single function

(negative or positive voltage converter).

q

 Changing the Temperature Gradient through Use of External

Temperature Sensor

   (Thermistor)

The SCI7661C/M has a temperature gradient selector circuit in its

regulator. It selects any one of the three gradients: –0.1% / 

°

C, –0.4% /

°

C and –0.6% / 

°

C. It is necessary that the temperature gradient can be

changed to any other value by connecting a thermistor in series to the

output voltage control resistor R

RV

.

background image

8

SCI7661C

OA

/M

OA

Plastic SOP5-14pin

Unit: mm

(inch)

8

14

7

1

INDEX

1.27

±

0.1

(

0.05

±

0.003

)

10.2

±

0.2

(

0.402        

)

5.5

±

0.2

(

0.217        

)

+0.007 –0.008

0.4

±

0.1

(

0.016        

)

+0.003

–0.004

2.2

max

(

0.086

max

)

0.15

±

0.1

(

0.006        

)

+0.003

–0.004

0.4

(

0.016

)

+0.007

–0.008

8

±

0.3

(

0.315

±

0.011

)

2.3

(

0.09

)

1.25

(

0.049

)

10.5

max

(

0.413

max

)

0.1

±

0.08

(

0.004

±

0.003

)

background image

9

SCI7661C

OA

/M

OA

ELECTRONIC DEVICES MARKETING DIVISION

Electronic Device Marketing Department

IC Marketing & Engineering Group

421-8, Hino, Hino-shi, Tokyo 191-8501, JAPAN

Phone: +81-(0)42-587-5816

Fax: +81-(0)42-587-5624

ED International Marketing Department 

I

 

(Europe & U.S.A.)

421-8, Hino, Hino-shi, Tokyo 191-8501, JAPAN

Phone: +81-(0)42-587-5812

Fax: +81-(0)42-587-5564

ED International Marketing Department 

II 

(Asia)

421-8, Hino, Hino-shi, Tokyo 191-8501, JAPAN

Phone: +81-(0)42-587-5814

Fax: +81-(0)42-587-5110

NOTICE

No part of this material may be reproduced or duplicated in any form or by any means without the written permission of Seiko

Epson. Seiko Epson reserves the right to make changes to this material without notice. Seiko Epson does not assume any liability

of any kind arising out of any inaccuracies contained in this material or due to its application or use in any product or circuit and,

further, there is no representation that this material is applicable to products requiring high level reliability, such as, medical

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©Seiko Epson Corporation 1998 All rights reserved.

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