SM8143A

SEIKO NPC CORPORATION —3

BLOCK DIAGRAM

PIN DESCRIPTION

Pin number

Name

I/O

Function

VSOP-16

SON-10

1

8

NC

–

No connection (must be open)

2

10

CHV

I

High-voltage DC input

3

–

NC

–

No connection (must be open)

4

9

LDR

O

Booster coil driver output

5

–

NC

–

No connection (must be open)

6

1

VSS

–

Ground

7

–

NC

–

No connection (must be open)

8

2

OCL

I

Coil driver oscillator (oscillator frequency determined by external resistor)

9

3

OCE

I

EL driver oscillator (oscillator frequency determined by external resistor)

10

4

ENA

I

Enable input (built-in pull-down resistor)

11

5

VDD

–

Supply

12

–

NC

–

No connection (must be open)

13

6

OUT2

O

Output 2

14

–

NC

–

No connection (must be open)

15

7

OUT1

O

Output 1

16

–

NC

–

No connection (must be open)

VSS

OCL

OCE

VDD

CHV

LDR

OUT2

OUT1

Oscillator for

Boosting

Switching Circuit

Dividing Circuit

1/4

Oscillator for

EL driving

Dividing Circuit

1/1024

ENA

Boosting Block

ENA from microcontroller

When ENA is logical "H", SM8143A is active.

Oscillation Block

EL sheet

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