AW9203

June 2018 V1.2

www.awinic.com.cn

12

Copyright © 2016 SHANGHAI AWINIC TECHNOLOGY CO., LTD

b)

Master device sends slave address (7-bit) and the data direction bit (w = 0).

c)

Slave device sends acknowledge signal if the slave address is correct.

d)

Master sends control register address (8-bit)

e)

Slave sends acknowledge signal

f)

Master generates STOP condition followed with START condition or REPEAT START condition

g)

Master device sends slave address (7-bit) and the data direction bit (r = 1).

h)

Slave device sends acknowledge signal if the slave address is correct.

i)

Slave sends data high 8Bit from addressed register.

j)

Master sends acknowledge signal

k)

Slave sends data low 8Bit from addressed register.

l)

If the master device sends acknowledge signal, the slave device will increase the control register

address by one, then send the next data from the new addressed register. If master sends no

acknowledge signal, the slave device stop to send data and wait for STOP condition.

m)

If the master device generates STOP condition, the read cycle is ended.

0

A2

A1

A0

A6

A5

A3

A4

A4

A3

A1

A2

A7

A5

A6

1

2

3

4

5

6

7

8

0

1

2

3

4

5

6

A4

A3

A1

A2

A0

A5

A6

D14

D8

D9

A0

D15

7

0

1

2

3

4

5

6

7

8

0

1

...

6

SCL

SDA

Ack

Ack

Ack

7

8

Ack

Start

R/W

……

I

Register Address

I

Register Data

High 8Bit

8

RS

Using

Repeat start

A4

A3

A1

A2

A5

A6

D14

D8

D9

A0

D15

0

1

2

3

4

5

6

7

8

0

1

...

6

Ack

7

8

Ack

……

Stop

Register Data

High 8Bit

S

Separated

Read/write

transaction

……

……

……

I

P

……

……

R/W

R/W

D6

D0

D1

D7

0

1

...

6

7

8

Ack

……

Stop

Register Data

Low 8Bit

D6

D0

D1

D7

0

1

...

6

7

8

Ack

……

Register Data

Low 8Bit

Figure 10

9.4

OSCILLATOR

An internal oscillator provides clock for both capacitive touch detecting circuit. If register bit GCR.SENE is high,

the OSC starts to work, the start-up time is about 5 us. When the register bit GCR.SENE are low, the internal

OSC stops.

9.5

CAPACITIVE TOUCH DETECTION

With high performance sigma-delta capacitive digital conversion technology, the capacitance on SX pin is

measured, the finger touch decision is made according to the increment of SX capacitance. Before finger

touching, the key capacitance is only formed by the sensing electrode and surrounding ground, which is called

intrinsic capacitance usually. When finger touching, an additional parallel plate capacitor capacitance

(electrode-media-finger) is formed, resulting in the capacitance increment on pin SX. In general, because of

the variation of different electrode size and dielectric characteristic of different media materials, the capacitance

increment caused by finger touch is about 0.5pF～5pF.