Technical Note

7/12

BD8115F-M

www.rohm.com

2009.12 - Rev.0.34

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3）Enable Signal

By applying voltage at least VCC×0.8 or more to the SDWN terminal, D0~D7 become open forcibly. At this time, the

temperature protection circuit (TSD) stops. D7～D0 become PWM operation by inputting PWM to SDWN.

4）SEROUT

A cascade connection can be made (connecting at least 2 or more IC’s in serial).

Serial signal input from SERIN is transferred into receiver IC by the fall edge of the CLK signal.

Since this functionality gives enough margins for the setup time prior to the rise edge of the CLK signal on the receiver

IC (using the exact same CLK signal of sender IC), the application reliability can be improved as cascade connection

functionality.

Fig.14

●

Cascade Connection

By using (at least) 2 ICs, each IC’s D7~D0, at (at least) 16ch, can be controlled by the 16-bit SERIN signal. The serial data

input to the sender IC can be transferred to the receiver IC by inputting 8CLK to the CLK terminal.

Send side IC

Receive side IC

Fig.15

LATCH

CLK

SERIN

d7

d6

d5

d4

d3

d2

d1

d0

12

3

4

5

6

78

SEROUT

D7

LATCH

CLK

SERIN

d15 d14 d13 d12

12

3

4

5

6

7

8

9

10

11

12

13

d11 d10

d9

d8

d7

d6

d5

d4

d3

d2

d1

14

15

16

d0