Technical Note

10/12

BU1851GUW

www.rohm.com

2009.09 - Rev.A

© 2009 ROHM Co., Ltd. All rights reserved.

● 3wire Interface AC characteristics

Fig.9 3wire interface AC timing

VDD=3.30V，Topr=25℃, CLKSEL=H (Sysclk = External Clock)

Item

Symbol

Min

Typ

Max

Unit

Condition

KSCL Clock Frequency

f

SCLK

-

-

21.5

kHz

START Condition

Setup Time

t

SU;STA

0.030

-

500

ms

START Condition

Hold Time

t

HD;STA

20

-

-

s

KSCL Low Time

t

LOW;CLK

23

-

-

s

KSCL High Time

t

HIGH;CLK

23

-

-

s

Data Setup Time

t

SU;DAT

t

(1/Sysclk)x12

-

t

(1/Sysclk)x10

s

Data Hold Time

t

HD;DAT

(1/Sysclk)x10

-

(1/Sysclk)x12

s

KINT End Hold Time

t

HD;INTE

(1/Sysclk)x3

-

(1/Sysclk)x5

s

KINT Low Time

t

LOW;INT

500

-

1200

ms

KSCL

KSDA

START

BIT 7

BIT 6

"0"

State

KINT

BIT 0