Pin Assignment

Pin Description

The pins in the following table are common to all devices.

Pin Name

I/O

Description

Key0~Keyn

Input

Touch key n input. These pins are connected to the external touch key.

Kout0~Koutn

Output

Touch key n output pin.

Cref

Input

Touch key reference capacitor input - value range of 0pF to 10pF - higher capacitance val-

ues result in higher sensitivities.

VSS

¾

Negative power supply, ground

VDD

¾

Positive power supply

The following table shows device specific pins.

Pin Name

I/O

Device

Description

OKW

Input

BS804B

BS806B

BS808B

Selects One-key wake-up or Any-key wake-up.

Pin condition is read during power-up. The logic status of this pin must not be

changed after power-on. After power-on this pin

¢s function can be overridden

by a serial command on relevant devices. Pin connected to an internal

pull-high resistor. Internal circuitry ensures that this pull high resistor will not

consume current even if the input is low.

Open: One-key wake-up using key0 only

Low: Any-Key wake-up

SCD

Input/

Output

BS804B

BS808B

Serial bus pin used to communicate with an external MCU. The external MCU

can read the BS804B or BS808B touch key status and also send commands

to the device via this pin.

LHF

Input

BS801B

BS802B

BS804B

Selects Key Output Type

Pin condition is read during power-up. The logic status of this pin must not be

changed after power-on. After power-on this pin

¢s function can be overridden

by a serial command on relevant devices. Pin connected to an internal

pull-high resistor. Internal circuitry ensures that this pull high resistor will not

consume current even if the input is low.

Open: Level-Hold output

Low: Toggle output

Note:

It is important that the logic level of the OKW and LHF pins do not change state after power-on.

BS801B/02B/04B/06B/08B

Rev. 1.00

2

July 7, 2009

1

2

3

4

8

7

6

5

K e y 0

K o u t 1

K o u t 0

V S S

C r e f

K e y 1

V D D

L H F

B S 8 0 2 B

8 S O P - A

1

2

3

4

8

7

6

5

K e y 1

K e y 2

K e y 3

C r e f

K e y 0

S C D

V D D

V S S

B S 8 0 4 B

8 S O P - A

B S 8 0 4 B

1 6 N S O P - A

1 6

1 5

1 4

1 3

1 2

1 1

1 0

9

1

2

3

4

5

6

7

8

K e y 0

K e y 1

K e y 2

K e y 3

C r e f

V S S

N C

N C

K o u t 0

K o u t 1

K o u t 2

K o u t 3

S C D

V D D

O K W

L H F

1 6

1 5

1 4

1 3

1 2

1 1

1 0

9

1

2

3

4

5

6

7

8

B S 8 0 6 B

1 6 N S O P - A

K e y 0

K e y 1

K e y 2

K e y 3

K e y 4

K e y 5

C r e f

V S S

K o u t 0

K o u t 1

K o u t 2

K o u t 3

K o u t 4

K o u t 5

V D D

O K W

2 0

1 9

1 8

1 7

1 6

1 5

1 4

1 3

1 2

1 1

1

2

3

4

5

6

7

8

9

1 0

B S 8 0 8 B

2 0 S O P - A / S S O P - A

K e y 0

K e y 1

K e y 2

K e y 3

K e y 4

K e y 5

K e y 6

K e y 7

C r e f

V S S

K o u t 0

K o u t 1

K o u t 2

K o u t 3

K o u t 4

K o u t 5

K o u t 6

K o u t 7

V D D

O K W

1 6

1 5

1 4

1 3

1 2

1 1

1 0

9

1

2

3

4

5

6

7

8

B S 8 0 8 B

1 6 N S O P - A

K e y 0

K e y 1

K e y 4

K e y 5

K e y 6

K e y 7

C r e f

N C

K e y 2

K e y 3

N C

N C

N C

S C D

V D D

V S S

K o u t V S S

T o p V i e w

L H F

C r e f

K e y

1

2

3

4

6

5

V D D

B S 8 0 1 B

S O T 2 3 - 6 - A