BS812A-1/BS813A-1/BS814A-1/BS814A-2 BS816A-1

BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
Touch Key
Features
General Description
• Operating voltage: 2.2V~5.5V
The BS81x is a series of 2~16 key touch key devices
which can detect human body contact using external
touch pads. The high level of device integration
enable applications to be implemented with a
minimum number of external components.
• Low standby current
• Auto-calibration
• Reliable touch detections
• Standby and normal operating modes
The BS81x series devices are equipped with serial or
parallel interfaces to allow easy communication with
an external MCU for device setup and for touch pin
monitoring purposes. Special internal circuitry is also
employed to ensure excellent power noise rejection to
reduce the possibility of false detections, increasing
the touch switch application reliability under adverse
environmental conditions.
• Maximum key on duration time detection
• Adaptive voltage drop function
• Level Hold, selectable active level- low or high
• NMOS output with internal pull-high/CMOSDirect Output • Both serial interface and parallel outputs
• Sensitivity adjustment using an external capacitor
With auto-calibration, low standby current, excellent
resistance to voltage fluctuation and other features,
this range of touch key devices provide a simple and
effective means of implementing touch key operation
in a wide variety of applications.
• Minimal number of external components
Selection Table
For this device series, most of the feature are similar. The BS8112A-3 and BS8116A-3 provide IIC function.
The BS814A-2 and BS818A-2 include a serial interface function while the BS812A-1, BS813A-1, BS814A-1
and BS816A-1 have parallel outputs. Meanwhile the BS8112A-3 and BS8116A-3 can set up some options and
the sensitivity through the IIC communication interface and the BS816A-1 and BS818A-2 include two hardware
options. The following table summarizes the main characteristics of each device.
Part. No.
Touch
Key
Option
[email protected]
BS812A-1
2-Key
×
2.0μA
BS813A-1
3-Key
×
4.5μA
Parallel Outputs
NMOS
(internal pull-high)
Serial
Auto
Power Mode
Interface
Calibration
Package
×
√
SOT23-6
×
√
8SOP
BS814A-1
4-Key
×
5.0μA
×
√
10MSOP
BS814A-2
4-Key
×
5.0μA
×
√
√
8SOP
BS816A-1
6-Key
OMS/LSC(Note 1)
12μA/6μA
NMOS
(internal pull-high)/
CMOS-Direct
×
√
16NSOP
BS818A-2
8-Key
OMS/LSC(Note 1)
12μA/6μA
Binary
√
√
16NSOP
BS8112A-3
12-Key
Note 2
13μA/3μA
×
IIC
√
16NSOP
BS8116A-3
16-Key
Note 2
17μA/3.5μA
×
IIC
√
20SOP/SSOP
Normal and
Standby
Note: 1. Refer to the OMS/LSC Option table.
2. Refer to the IIC Option table.
Rev. 1.20
1
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
Pin Assignment
Key1
Key2
Kout2
SOT23-6
6
5
4
12A-1
2
3
VDD
VSS
Kout1
VDD
Key1
Key2
Key3
Key4
1
1
10
2
9
3
8
4
7
5
6
Top View
1
8
VDD
Key2
2
7
VSS
Key3
3
6
Kout1
Kout3
4
5
Kout2
BS813A-1
8SOP-A
VSS
Kout1
Kout2
Kout3
Kout4
Key1
1
16
Kout1
Key2
2
15
Kout2
Key3
3
14
Kout3
Key4
4
13
Kout4
Key5
5
12
Kout5
Key6
6
11
Kout6
OMS
7
10
VDD
LSC
8
9
VSS
1
16
Key2
Key4
2
15
Key1
Key5
3
14
SDA
Key6
4
13
SCL
Key7
5
12
VDD
Key8
6
11
VSS
Key9
7
10
Key12/IRQ
Key10
8
9
1
8
VDD
Key2
2
7
VSS
Key3
3
6
Data
Key4
4
5
Clock
Key1
1
16
BIN3/Data
Key2
2
15
BIN2/Clcok
Key3
3
14
BIN1
Key4
4
13
BIN0
Key5
5
12
OMS
Key6
6
11
LSC
Key7
7
10
VDD
Key8
8
9
VSS
BS818A-2
16 NSOP-A
BS816A-1
16 NSOP-A
Key3
Key1
BS814A-2
8SOP-A
BS814A-1
10MSOP-A
Key11
BS8112A-3
16 NSOP-A
Rev. 1.20
Key1
Key3
1
20
Key2
Key4
2
19
Key1
Key5
3
18
SDA
Key6
4
17
SCL
Key7
5
16
VDD
Key8
6
15
VSS
Key9
7
14
Key16/IRQ
Key10
8
13
Key15
Key11
9
12
Key14
Key12
10
11
Key13
BS8116A-3
20 SOP-A/SSOP-A
2
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
Pin Description
BS812A-1
Pin name
Key1~Key2
Kout1~Kout2
I/O
Input
NMOS output
Description
Touch key input pin, unused touch keys require grounding
Touch key output pin with internal pull high
VSS
—
Negative power supply, ground
VDD
—
Positive power supply
BS813A-1
Pin name
Key1~Key3
Kout1~Kout3
I/O
Input
NMOS output
Description
Touch key input pin, unused touch keys require grounding
Touch key output pin with internal pull high
VSS
—
Negative power supply, ground
VDD
—
Positive power supply
BS814A-1
Pin name
Key1~Key4
Kout1~Kout4
I/O
Input
NMOS output
Description
Touch key input pin, unused touch keys require grounding
Touch key output pin with internal pull high
VSS
—
Negative power supply, ground
VDD
—
Positive power supply
BS814A-2
Pin name
Key1~Key4
I/O
Description
Input
Touch key input pin, unused touch keys require grounding
Clock
Input
2-wire series interface Clock input with internal pull high
Data
NMOS output
VSS
—
Negative power supply, ground
VDD
—
Positive power supply
2-wire series interface Date NMOS output with internal pull high
BS816A-1
Pin name
I/O
Description
Key1~Key6
Input
Touch key input pin, unused touch keys require grounding
OMS
Input
Output Mode Selection.
Open=NMOS output (low active)
Grounded=CMOS-Direct output (high active)
LSC
Input
Power-saving mode selection
Open= General power-saving mode
Grounded=More power-saving mode
Kout1~Kout6
NMOS output
CMOS output
OMS open, NMOS output with internal pull-high.
OMS grounded, CMOS-Direct output
VSS
—
Negative power supply, ground
VDD
—
Positive power supply
Rev. 1.20
3
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
BS818A-2
Pin name
I/O
Description
Key1~Key8
Input
Touch key input pin, unused touch keys require grounding
OMS
Input
Output Mode Selection.
Open = 2-wire serial mode
Grounded = 4-wire binary parallel mode
LSC
Input
Power-saving mode selection
Open=General power-saving mode
Grounded=More power-saving mode
Clock
Input
2-wire series interface Clock input - internal pull- high
Data
NMOS output
Series interface Data NMOS output - internal pull-high
BIN3~BIN0
CMOS output
Binary output mode
VSS
—
Negative power supply, ground
VDD
—
Positive power supply
BS8112A-3
Pin name
Key1~Key12
I/O
Input
Description
Touch key input pin, unused touch keys require grounding
IRQ
Output
SCL
Input / Output
Interrupt request or wake-up function, NMOS output with internal pull high
IIC clock input/output
SDA
Input / Output
IIC data input/output
VSS
—
Negative power supply, ground
VDD
—
Positive power supply
BS8116A-3
Pin name
Key1~Key16
I/O
Input
Description
Touch key input pin, unused touch keys require grounding
IRQ
Output
SCL
Input / Output
Interrupt request or wake-up function, NMOS output with internal pull high
IIC clock input/output
SDA
Input / Output
IIC data input/output
VSS
—
Negative power supply, ground
VDD
—
Positive power supply
Absolute Maximum Ratings
Supply Voltage.........................VSS -0.3V to VSS +6.5V
Storage Temperature............................ -50°C to 125°C
Input Voltage............................VSS -0.3V to VDD +0.3V
Operating Temperature.......................... -40°C to 85°C
IOL Total............................................................... 80mA
Total Power Dissipation...................................500mW
IOH Total.............................................................. -80mA
Note: These are stress ratings only. Stresses exceeding the range specified under “Absolute Maximum Ratings”
may cause substantial damage to the device. Functional operation of this device at other conditions beyond
those listed in the specification is not implied and prolonged exposure to extreme conditions may affect
device reliability.
Rev. 1.20
4
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
D.C. Characteristics
Symbol
VDD
Test Conditions
Parameter
VDD Conditions
Operating Voltage
Operating Current (BS812A-1)
Operating Current (BS813A-1/BS814A-1/BS814A-2)
IDD
Operating Current (BS816A-1/BS818A-2)
Operating Current (BS8112A-3/BS8116A-3)
Standby Current (BS812A-1)(Note 1)
Standby Current (BS813A-1)(Note 1)
Standby Current (BS814A-1/BS814A-2)(Note 1)
Standby Current (BS816A-1/BS818A-2)(Note 1)
LSC=VSS (Note 2)
Standby Current (BS816A-1/BS818A-2)(Note 1)
LSC=Open (Note 2)
ISTB
Standby Current
(BS8112A-3)(Note 1)
LSC enable(Note 3)
Any one key wake up
Standby Current
(BS8112A-3)(Note 1)
LSC disable(Note 3)
Any one key wake up
Standby Current
(BS8116A-3)(Note 1)
LSC enable(Note 3)
Any one key wake up
Standby Current
(BS8116A-3)(Note 1)
LSC disable(Note 3)
Any one key wake up
All keys wake up
All keys wake up
All keys wake up
All keys wake up
VIL
Input Low Voltage for Clock, SCL or SDA pin
VIH
Input High Voltage for Clock, SCL or SDA pin
IOL
Kout/Data/SDA/SCL Sink Current (NMOS)
IOH
BIN0~BIN3 Source Current (CMOS)
RPH
Pull-high Resistance to Clock/Kout /SDA/SCL/IRQ pin
—
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
3V
5V
5V
—
5V
—
3V
5V
3V
5V
3V
5V
—
No load
No load
No load
No load
No load
No load
No load
No load
No load
No load
No load
No load
No load
—
—
—
—
VOL=0.1VDD
VOL=0.1VDD
VOH=0.9VDD
VOH=0.9VDD
—
—
Min.
Typ.
Max.
Unit
2.2
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
0
0
3.5
0.8VDD
4
10
-2
-5
20
10
—
0.6
1.2
1.2
2.2
1.2
2.2
1.2
2.2
2
4
4.5
9
5.0
10
6.0
12
12
25
3
6
6.5
13
6
12
13
27
3.5
7
9
18
7
14
17
34
—
—
—
—
8
20
-4
-10
60
30
5.5
0.9
1.8
1.8
3.3
1.8
3.3
1.8
3.3
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1.5
0.2VDD
5.0
VDD
—
—
—
—
100
50
V
mA
mA
mA
mA
mA
mA
mA
mA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
μA
V
V
V
V
mA
mA
mA
mA
kΩ
kΩ
Note: 1. ISTB is the average standby current.
2. Refer to the OMS/LSC Option table
3. Refer to the IIC Option table
Rev. 1.20
5
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
A.C. Characteristics
Symbol
tKRT
tKH
tCAL
tNS
Ta = 25°C
Test Conditions
Parameter
Min.
Typ.
Max. Unit
—
100
125
150
ms
—
100
150
250
ms
VDD
Conditions
Key Response Time --Normal Mode
—
Key Response Time --Standby Mode
BS812A-1 / BS813A-1
BS814A-1 / BS814A-2
—
Key Response Time --Standby Mode
BS816A-1/BS818A-2
—
LSC=Open (Disable)
100
150
250
ms
—
LSC=VSS (Enable)
400
600
1000
ms
Key Response Time -- Standby Mode
(BS8112A-3/BS8116A-3)
—
LSC Disable / IRQ Enable
100
150
250
ms
—
LSC Enable / IRQ Enable
400
600
1000
ms
Maximum Key Hold Time
—
—
60
64
68
s
Auto-Calibration Period -- Normal Mode
—
—
—
1
—
s
Auto-Calibration Period -- Standby Mode
—
—
—
32
—
s
Normal to Standby Mode conversion time
—
—
7
8
9
s
Serial Interface Characteristics
BS814A-2/BS818A-2
Symbol
Parameter
Test Conditions
VDD
Conditions
Min.
Typ.
Max.
Unit
TSTART
Start bit low time
—
—
—
—
tNS
s
TLOW
Clock low time
—
—
20
—
—
μs
THIGH
Clock high time
—
—
20
—
—
μs
TBR
Data transfer rate
—
—
—
—
25
Kbps
TED
Delay time between a error reading
and the next reading
—
—
6
—
—
ms
Min.
Typ.
Max.
Unit
μs
IIC Interface Characteristics
BS8112A-3/BS8116A-3
Symbol
Parameter
Test Conditions
VDD
Conditions
TLOW
Clock low time
—
—
5
—
—
THIGH
Clock high time
—
—
5
—
—
μs
TBR
Data transfer rate
—
—
—
—
100
Kbps
Rev. 1.20
6
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
Functional Description
IIC Option table
BS8112A-3 and BS8116A-3 provide 4 options can be
setup by IIC communication interface.
Introduction
This range of BS81x touch key devices offer an
easy and reliable means of implementing touch
switch functions in a wide range of applications
which require 2~16 touch keys. Very few external
c o m p o n e n ts are re q u ire d fo r fu ll to uc h ke y
implementations. In addition to simple parallel output,
a two-wire serial interface and binary output offer a
convenient communication with an external MCU.
• IRQ_OMS Option
Address bit7 bit6 bit5 bit4 bit3 bit2 bit1
0B0H
Name
0B4H
LSC
The BS816A-1 and BS818A-2 provide two options to
enhance application flexibility.
• OMS Option
Rev. 1.20
bit6
bit5 bit4 bit3 bit2 bit1 bit0 R/W
LSC
R/W
Description
Open
NMOS output with internal
pull-high, low active
Vss
CMOS output, high active
Vss
1
Function
0: General power-saving
1: More power-saving
(wake-up time of 0.5 ~1s)
• Touch Key Wake-up Option
OMS Output Mode
Selection
Address
BS8112A-3
0B5H~0C0H
BS8116A-3
0B5H~0C4H
Name
bit7
bit6
Kn_TH
KnWU
0
Name Default
2-wire serial mode
KnWU
4-wire Binary parallel
mode
0
bit5
bit4
bit3
bit2
bit1
Key n Trigger threshold value
bit0
R/W
R/W
Function
0: Enable wake-up function
1: Disable wake-up function
Operating Mode
• LSC Option
BS816A-1/
BS818A-2
0
Address bit7
OMS/LSC Option table
BS818A-2
Function
0: Level hold, low active
1: One-shot, low active
Name Default
Open
R/W
• LSC Option
Option table
BS816A-1
Default
IRQ_OMS
Sensitivity adjustment is also an easy matter. By the
simple connection of a small capacitor to the touch
key input pin, the changes in the capacitor value will
be reflected in different sensitivity values. By having a
fully integrated adaptive voltage drop function, touch
switch applications can save on the usually required
LDO.
bit0
IRQ_
R/W
OMS
LSC- Lower
Standby Current
Description
Open
General power-saving
Vss
There are two operating modes for this device series,
the normal mode and the standby mode. During the
8 seconds after power-on, if no touch key actions
are detected, the devices will automatically enter the
standby mode to reduce their power consumption.
If a key or keys are pressed, the device will be
woken up and will then enter the normal mode and
output the key state value until all keys are released.
After 8 seconds, the system will then revert to the
standby mode again. Note that the BS8112A-3 and
BS8116A-3 devices can set up the wake-up keys
individually.
More power-saving
(wake-up time of
0.5~1s)
7
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
Touch Key Outputs
4-key Data Format
After a clock signal is received on the Clock pin, an
8-bit data byte will be generated by the touch key
device and shifted out on the Data pin. Data bits,
bit6~bit4, will also generate a checksum whose
content informs how many touch keys have been
touched. For example, if the checksum is equal to
“010”, it means that two keys have been touched. As
to which keys are actually touched, this information
can be retrieved from the condition of data bits,
bit3~bit0. The state of the data bits, bit3~bit0, is used
to indicate which touch keys, key4~key1, are touched
or not respectively. A low bit means the corresponding
key is touched. Otherwise, the key is not touched if
the corresponding data condition is high.
For the BS812A-1, BS813A-1 and BS814A-1 devices,
all output pins are NMOS structures with connected
internal pull-high resistors without requiring
external resistors. The non touch detect output logic
level is high. When a touch action is detected, the
corresponding output will change to a low state.
For the BS816A-1 device, except the NMOS output
type, users can also select a CMOS output type. The
non touch detect output logic level is low. When a
touch action is detected, the corresponding output will
change to a high state.
Serial Interface
Start bit:When a key changes state, the Data pin
outputs a low, which can wake up the master, which
can then read the key status.
Both the BS814A-2 and BS818A-2 are equipped with
a serial interface allowing for easy interfacing to an
external master MCU. When the device detects that
a touch key has been pressed, it will output a low on
the Data pin which can be used to wake up the master
MCU. After receiving this low level, the master can
then send a clock signal to the Clock pin and read
back the key status from the Data pin.
Bit0: Key1 state - “0”= touch, “1”= no touch
Bit1: Key2 state - “0”= touch, “1”= no touch
Bit2: Key3 state - “0”= touch, “1”= no touch
Bit3: Key4 state - “0”= touch, “1”= no touch
When a low clock signal is received the key status
data is prepared by the touch key device. When the
clock signal changes to a high level, the master reads
the touch key status data from the Data line. The
timings associated with the communication protocol
can be fully described within 8 clock periods. Without
waiting for a start bit, the touch key status condition
can also be directly read using a polling method. If
there are any errors in reading the data, it is necessary
to wait for about 6ms and then read the data again.
Data
Start bit
Bit0
Clock
Bit1
Bit2
Bit3
Bit4
Bit5
Bit6
Bit6~4: Checksum – the total number of “0”s is
used to indicate how many keys have been
touched.
Bit7: Stop bit, always a “1”, high level.
Bit0
Bit7
Stop bit
Bit1
Bit2
Bit3
Bit4
Bit5
Bit6
Bit7
Stop bit
Thigh
Tlow
Ted
Tbr
Data Transfer Timing – BS814A-2
Bit
7
Stop
Function
bit
Data
Stream
1
6~4
3~0
Descriptions
Check
Sum
Key4 ~ Key1 state
0: touched / 1: not touched
100
0000
Check Sum = 100, Four keys are touched.
011
0001, 0010, 0100 or 1000
Check Sum = 011, Three keys are touched.
010
0011, 0101, 0110, 1001, 1010 or 1100 Check Sum = 010, Two keys are touched.
001
0111, 1011, 1101 or 1110
Check Sum = 001, One key is touched.
000
1111
Check Sum = 000, No key is touched.
4-key Serial Data Stream Format
Rev. 1.20
8
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
Data
Start bit
Bit0
Clock
Bit1
Bit2
Bit3
Bit4
Bit5
Bit6
Bit7
Bit8
Bit9
Bit10
Bit11
Bit12
Bit13
Bit14
Bit15
Stop bit
Thigh
Tlow
Tbr
Data Transfer Timing – BS818A-2
8-key Data Format
After a clock signal is received on the Clock pin, a 16-bit data byte will be generated by the touch key device and
shifted out on the Data pin. Data bits, bit11~bit8, will also generate a checksum whose content informs how many
touch keys have been touched. For example, if the check sum is equal to “0010”, it means that two keys have
been touched. As to which keys are actually touched, this information can be retrieved from the condition of data
bits, bit7~bit0. The state of the data bits, bit7~bit0, is used to indicate which touch keys, key8~key1, are touched
or not respectively. A low bit means the corresponding key is touched. Otherwise, the key is not touched if the
corresponding data condition is high.
Start bit:When a key state is changed, Data pin outputs a low, which can wake up the master, which can then read
the key status.
Bit0: Key1 state - “0”= touch, “1”= no touch
Bit1: Key2 state - “0”= touch, “1”= no touch
Bit2: Key3 state - “0”= touch, “1”= no touch
Bit3: Key4 state - “0”= touch, “1”= no touch
Bit4: Key5 state - “0”= touch, “1”= no touch
Bit5: Key6 state - “0”= touch, “1”= no touch
Bit6: Key7 state - “0”= touch, “1”= no touch
Bit7: Key8 state - “0”= touch, “1”= no touch
Bit11~8: Checksum – the total number of “0”s is used to indicate how many keys have been touched.
Bit15~12: Stop bits, always “1010B”.
Bit
Function
15~12
11~8
Stop Check
bit
Sum
7~0
Descriptions
Key8 ~ Key1 state
0: touched / 1: not touched
1000 00000000
Data
Stream
1010
Check Sum = 1000, 8 keys are touched.
0111
00000001, 00000010, 00000100, 00001000
Check Sum = 0111, 7 keys are touched.
00010000, 00100000, 01000000 or 10000000
0110
00000011, 00000110, 00011000, 00110000
11000000 or 10000001 ……
Check Sum = 0110, 6 keys are touched.
0101
00000111, 00001110, 11100000, 10000011,
10000110, 10001100 or 10011000……
Check Sum = 0101, 5 keys is touched.
0100
00001111, 00011110, 00111100, 01111000,
11110000 or 10000111……
Check Sum = 0100, 4 keys is touched.
0011
00011111, 00111110, 01111100, 11111000
100011111 or 110001111……
Check Sum = 0011, 3 keys are touched.
0010
00111111, 01111110, 11111100,
01111110, 01111101or 01111011……
Check Sum = 0010, 2 keys are touched.
0001
11111110, 11111101, 11111011, 11110111
11101111, 11011111, 10111111 or 01111111
Check Sum = 0001, 1 key is touched.
0000 11111111
Check Sum = 0000, No key is touched.
Serial Data Stream Format for 8-key
Rev. 1.20
9
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
Parallel Interface
Read or Write Control
The BS818A-2 also provides a parallel interface
function which shows directly the key state condition.
When the parallel output type is selected, the touch
key data reflects only one key state, not more keys,
at the same time. When no touch key is pressed,
BIN3~BIN0 are high. When any key is pressed,
BIN3 must output a low to wake up the master while
BIN2~BIN0 reflect which keys are pressed as shown
in the following table.
SDA
SCL
1
2
7
8
R/W
0: Write
1: Read
9
2
7
8
9
Acknowledge
SDA
SCL
1
ACK
0: Acknowledge
1: No acknowledge
Pressed key
BIN3
BIN2
BIN1
BIN0
No key
1 (high)
1
1
1
Key1
0 (low)
1
1
1
Slave Busy
After a date byte (8bit+ACK) is transmitted, the slave
device is busy with processing the received data(
slave busy) and cannot receive the next data byte. At
this time the SCL line is pulled down and the master
can continue to transmit the data until the SCL line is
pulled high again.
Key2
0
1
1
0
Key3
0
1
0
1
Key4
0
1
0
0
Key5
0
0
1
1
Key6
0
0
1
0
Key7
0
0
0
1
Key8
0
0
0
0
SDA
SCL
1
2
7
8
9
BUSY
IIC Interface
• Read:
SDA
START and STOP Conditions:
SCL
1
2
3
4
5
6
7
8
9
BUSY
SDA
• Write:
SDA
SCL
START
SCL
STOP
1
2
3
4
5
6
7
8
9
BUSY
Slave Address
After the START signal, a 7-bit slave address will be
transmitted. The slave address is 0x50.
SDA
SCL
1
2
Slave
Address(7bit)
8
7
9
Read Touch-key Status Data Register
Read the touch key status data structure of the BS8112-3 or BS8116A-3.
Start
Slave
Address
A
W C
K
A
W C
K
0x08
A
C
K
Slave
Start
Address
A
C
R K
0x09
A
C
K
Slave
Start
Address
A
C
R K
Start
Slave
Address
Start
A
Slave W C 0x08
K
Address
Rev. 1.20
A
C
K
Start
Slave
Address
A
C
R K
NO ACK
KeyStatus0
NO ACK
KeyStatus1
KeyStatus0
10
Stop
A
C
K
Stop
NO ACK
KeyStatus1
Stop
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
BS8112A-3 and BS8116A-3 Touch-key Status Data Registers
Address
Name
08H
KeyStatus0
Key8
Key7
KeyStatus1
Key16
(Note)
Key15
(Note)
09H
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
R/W
Key6
Key5
Key4
Key3
Key2
Key1
R
Key14
(Note)
Key13
(Note)
Key12
Key11
Key10
Key9
R
Note: Key16~Key13 are only for the BS8116A-3 device.
0=no touch, 1=touch
BS8112A-3 Write Setting Register
When the master will write the setting byte to the BS8112A-3, it must write 18 date bytes consecutively with the
start byte of 0xB0 and the last byte of the checksum.
Slave
Address
Start
W
A
C
K
0xB0
A
C
K
Slave
Address
Start
A
C
K
A
C DATA1
K
W
DATA2~16
A
C DATA17
K
NO ACK
A
C CheckSum
Stop
K
When change the setting, the key reset and 0.5s later, the touch key status output.
BS8112A-3 Read Setting Register
The master read a setting byte of the BS8112A-3.
Slave
Address
Start
A
W C
K
A
C
K
0xB0~0xC0
Start
Slave
Address
R
NO ACK
A
C
K
DATA
Stop
The master read n setting bytes of the BS8112A-3.
Start
Slave
Address
A
A
W C Address C
K
K
Start
Slave
Address
A
A
R C DATA1 C
K
K
DATA
NO ACK
A
C DATAn
Stop
K
BS8112A-3 Touch-key Setting Registers
Address
Name
B0H
Option1
bit7
bit6
bit5
bit4
bit3
bit2
bit1
B1H
Reserve
B2H
B3H
B4H
Option2
1
LSC
B5H
K1_TH
K1WU
0
Key1 Trigger threshold value
R/W
B6H
K2_TH
K2WU
0
Key2 Trigger threshold value
R/W
B7H
K3_TH
K3WU
0
Key3 Trigger threshold value
R/W
B8H
K4_TH
K4WU
0
Key4 Trigger threshold value
R/W
—
bit0
R/W
IRQ_OMS
R/W
0x00
R/W
Reserve
0x83
R/W
Reserve
0xF3
0
1
1
R/W
0
0
0
R/W
B9H
K5_TH
K5WU
0
Key5 Trigger threshold value
R/W
BAH
K6_TH
K6WU
0
Key6 Trigger threshold value
R/W
BBH
K7_TH
K7WU
0
Key7 Trigger threshold value
R/W
BCH
K8_TH
K8WU
0
Key8 Trigger threshold value
R/W
BDH
K9_TH
K9WU
0
Key9 Trigger threshold value
R/W
BEH
K10_TH
K10WU
0
Key10 Trigger threshold value
R/W
BFH
K11_TH
K11WU
0
Key11 Trigger threshold value
R/W
C0H
K12_TH
K12WU
Mode
Key12 Trigger threshold value
R/W
BS8112A-3 Key12/IRQ Function Selection
Key12 Mode( bit6 of K12_TH)
Rev. 1.20
Function
0
Key12
1
IRQ (Default)
11
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
BS8116A-3 Write Setting Register
When the master will write the setting byte to the BS8116A-3, it must write 22 date bytes consecutively with the
start byte of 0xB0 and the last byte of the checksum.
Start
Slave
Address
A
W C
K
0xB0
A
C
K
Slave
Start
Address
NO ACK
A
A
A
A
C
C
C
C
W
CheckSum
DATA21
DATA1
DATA2~20
Stop
K
K
K
K
BS8116A-3 Read Setting Register
The master read a setting byte of the BS8116A-3.
A
W C
K
Slave
Address
Start
A
C
K
0xB0~0xC4
Start
Slave
Address
R
NO ACK
A
C
K
DATA
Stop
The master read n setting bytes of the BS8116A-3.
Start
Slave
Address
A
A
W C Address C
K
K
Slave
Start
Address
A
A
R C DATA1 C
K
K
DATA
NO ACK
A
C DATAn
Stop
K
When change the setting, the key reset and 0.5s later, the touch key status output.
BS8116A-3 Touch-key Sensitivity Setting Register
Address
Name
bit7
bit6
bit5
bit4
bit3
bit2
bit1
—
bit0
R/W
IRQ_OMS
R/W
B0H
Option1
B1H
Reserve
0x00
R/W
B2H
Reserve
0x83
R/W
B3H
Reserve
0xF3
B4H
Option2
1
LSC
B5H
K1_TH
K1WU
0
Key1 Trigger threshold value
R/W
B6H
K2_TH
K2WU
0
Key2 Trigger threshold value
R/W
B7H
K3_TH
K3WU
0
Key3 Trigger threshold value
R/W
B8H
K4_TH
K4WU
0
Key4 Trigger threshold value
R/W
B9H
K5_TH
K5WU
0
Key5 Trigger threshold value
R/W
BAH
K6_TH
K6WU
0
Key6 Trigger threshold value
R/W
0
1
1
R/W
0
0
0
R/W
BBH
K7_TH
K7WU
0
Key7 Trigger threshold value
R/W
BCH
K8_TH
K8WU
0
Key8 Trigger threshold value
R/W
BDH
K9_TH
K9WU
0
Key9 Trigger threshold value
R/W
BEH
K10_TH
K10WU
0
Key10 Trigger threshold value
R/W
BFH
K11_TH
K11WU
0
Key11 Trigger threshold value
R/W
C0H
K12_TH
K12WU
0
Key12 Trigger threshold value
R/W
C1H
K13_TH
K13WU
0
Key13 Trigger threshold value
R/W
C2H
K14_TH
K14WU
0
Key14 Trigger threshold value
R/W
C3H
K15_TH
K15WU
0
Key15 Trigger threshold value
R/W
C4H
K16_TH
K16WU
Mode
Key16 Trigger threshold value
R/W
Rev. 1.20
12
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
Maximum Key On Duration Time
BS8116A-3 Key16/IRQ Function Selection
Key16 Mode( bit6 of K16_TH)
To minimise the possibility of unintentional switch
detections, such as undesired objects covering the
sensing electrodes, the devices include a Maximum
Key On duration time function. To implement this
function the devices include an internal timer, which
starts running after each switch detection. If the key
on time of a touch key exceeds a value of about 64
seconds, then the device will re-calibrate the key state,
obtain a new reference value, while the output status
is reset to the initial state.
Function
0
Key16
1
IRQ (Default)
BS8112A-3, BS8116A-3 IRQ_OMS Function
IRQ_OMS ( bit0 of Option1)
Function
0
Level hold (Default)
1
One-shot
Auto-calibration Function
BS8112A-3, BS8116A-3 Touch-key Wake-up
Function Control
KnWU (bit7 of Kn_TH)
Function
0
Wake-up function enabled
(Default)
1
Wake-up function disabled
The devices include a full auto-calibration function
which will be initiated after the device is poweredon. In addition to the power-on calibration, if no
switch detection has been made for about more than
1 second in the normal mode or 32 seconds in the
standby mode, then a further calibration procedure
will be carried out. By implementing this feature,
changes in the touch key environmental conditions
are automatically catered for dynamically.
IRQ Function
Output mode: IRQ_OMS = 0 (Level hold, low active)
Adaptive Voltage Drop
The master reads the key data when the IRQ is low
and will stop reading data until the key data is 0.
Release all keys
IRQ
This series of touch key devices include an adaptive
voltage drop function which prevent touch key
malfunction due to power supply voltage variations
which may be caused by high current switching. With
the adaptive voltage drop function, there is no need
for an external LDO to deal with these voltage drop
issues.
Release all keys
Touch any key
Key Status ≠ 0
Key Status ≠ 0
Key Status = 0
Output mode: IRQ_OMS = 1 (One-shot, low active)
Sensitivity Adjustment
When the key status changes, send one-shot signal.
IRQ
The sensitivity of the switch is a very important
consideration in most applications whose requirements
will vary according to the user application. The user
should therefore be aware of the methods which can
adjust the sensitivity of their touch key application.
Changing the PCB electrode size, the conductive
layout area below the electrode and the thickness
of the dielectric material panel can all be used to
adjust the touch switch sensitivity. Additionally for
the BS81x device series, except the BS8112A-3 and
BS8116A-3 devices, an external capacitor connected
to the touch key input pin can also be used to adjust
the sensitivity for different applications. While for
the BS8112A-3 and BS8116A-3 devices, changing
related settings through the IIC can be used to adjust
the sensitivity for different demands.
Status unchanged
Status unchanged
Status change
Read
When the IRQ function is disabled, the Key12 of the
BS8112A-3 or the Key16 of BS8116A-3 is used as the
touch key. When the master read “KeyStatus=0x00”,
which means all the keys is released, the master
can reduce the reading speed and make the power
consumption lower, the corresponding, the key
response speed will also slow down.
The touch threshold adjustment range is from 8~63.
Rev. 1.20
13
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
Application Circuits
BS812A-1
VDD
Touch Key
KEY1
VDD
Ct 1
Touch Key
0.1 F
KEY2
KOUT1
Ct 2
KOUT2
VSS
Ct range 0pF~25pF
BS812A-1
Note: 1. Ct (C threshold) is used for adjustment of Trigger Threshold. Recommended value: 0~25 pF
2. Ct value can be changed to obtain different sensitivity values. Higher Ct values will result in lower sensitivity levels. (0pF = no Ct)
BS813A-1
VDD
Touch Key
KEY1
VDD
Ct 1
0.1 F
Touch Key
KEY2
Ct 2
KOUT1
Touch Key
KOUT2
KEY3
Ct 3
Ct range 0pF~25pF
KOUT3
VSS
BS813A-1
Note: 1. Ct (C threshold) is used for adjustment of Trigger Threshold. Recommended value: 0~25 pF
2. Ct value can be changed to obtain different sensitivity values. Higher Ct values will result in lower sensitivity levels. (0pF = no Ct)
Rev. 1.20
14
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
BS814A-1
Touch Key
VDD
KEY1
Ct 1
VDD
0.1 F
Touch Key
KEY2
Ct 2
Touch Key
KEY3
KOUT1
Ct 3
KOUT2
Touch Key
KEY4
KOUT3
Ct 4
KOUT4
VSS
Ct range 0pF~25pF
BS814A-1
Note: 1. Ct (C threshold) is used for adjustment of Trigger Threshold. Recommended value: 0~25 pF
2. Ct value can be changed to obtain different sensitivity values. Higher Ct values will result in lower sensitivity levels. (0pF = no Ct)
BS814A-2
Touch Key
VDD
KEY1
Ct 1
VDD
0.1 F
Touch Key
KEY2
Ct 2
Touch Key
KEY3
Data
Ct 3
Clock
Touch Key
KEY4
Ct 4
Ct range 0pF~25pF
VSS
BS814A-2
Note: 1. Ct (C threshold) is used for adjustment of Trigger Threshold. Recommended value: 0~25 pF
2. Ct value can be changed to obtain different sensitivity values. Higher Ct values will result in lower sensitivity levels. (0pF = no Ct)
Rev. 1.20
15
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
BS816A-1
Touch Key
VDD
KEY1
Ct 1
VDD
0.1 F
Touch Key
KEY2
Ct 2
Touch Key
KEY3
Ct 3
KOUT1
KOUT2
KOUT3
Touch Key
KEY4
Ct 4
KOUT4
KOUT5
Touch Key
KEY5
Ct 5
Touch Key
KOUT6
OMS
KEY6
Ct 6
Ct range 0pF~25pF
LSC
VSS
BS816A-1
16 NSOP
Note: 1. Ct (C threshold) is used for adjustment of Trigger Threshold. Recommended value: 0~25 pF
2. Ct value can be changed to obtain different sensitivity values. Higher Ct values will result in lower sensitivity levels. (0pF = no Ct)
Rev. 1.20
16
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
BS818A-2 – Serial Interface Mode
Touch Key
KEY1
VDD
Ct 1
VDD
Touch Key
0.1 F
KEY2
Ct 2
Touch Key
KEY3
Ct 3
Touch Key
KEY4
Ct 4
Data
Touch Key
KEY5
Clock
Ct 5
Touch Key
KEY6
Ct 6
Touch Key
KEY7
Ct 7
Touch Key
OMS
KEY8
Ct 8
Ct range 0pF~25pF
LSC
VSS
BS818A-2
Note: 1. Ct (C threshold) is used for adjustment of Trigger Threshold. Recommended value: 0~25 pF
2. Ct value can be changed to obtain different sensitivity values. Higher Ct values will result in lower sensitivity levels. (0pF = no Ct)
Rev. 1.20
17
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
BS818A-2 – Parallel Interface Mode
Touch Key
KEY1
VDD
Ct 1
VDD
Touch Key
0.1 F
KEY2
Ct 2
Touch Key
KEY3
Ct 3
Touch Key
KEY4
Ct 4
BIN3
Touch Key
KEY5
BIN2
Ct 5
BIN1
Touch Key
BIN0
KEY6
Ct 6
Touch Key
KEY7
Ct 7
Touch Key
OMS
KEY8
Ct 8
Ct range 0pF~25pF
LSC
VSS
BS818A-2
Note: 1. Ct (C threshold) is used for adjustment of Trigger Threshold. Recommended value: 0~25 pF
2. Ct value can be changed to obtain different sensitivity values. Higher Ct values will result in lower sensitivity levels. (0pF = no Ct)
Rev. 1.20
18
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
BS8112A-3
Touch Key
VDD
KEY1
VDD
0.1 F
SDA
Touch Key
KEY12/IRQ
SCL
VSS
BS8112A-3
BS8116A-3
Touch Key
VDD
KEY1
VDD
0.1 F
SDA
Touch Key
KEY16/IRQ
SCL
VSS
BS8116A-3
Rev. 1.20
19
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
Package Information
Note that the package information provided here is for consultation purposes only. As this information may be
updated at regular intervals users are reminded to consult the Holtek website for the latest version of the package
information.
Additional supplementary information with regard to packaging is listed below. Click on the relevant section to be
transferred to the relevant website page.
• Further Package Information (include Outline Dimensions, Product Tape and Reel Specifications)
• Packing Meterials Information
• Carton information
•
Rev. 1.20
20
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
6-pin SOT23-6 Outline Dimensions
Symbol
A
Min.
Nom.
Max.
—
—
0.057
0.006
A1
—
—
A2
0.035
0.045
0.051
b
0.012
—
0.020
C
0.003
—
0.009
D
—
0.114 BSC
—
E
—
0.063 BSC
—
e
—
0.037 BSC
—
e1
—
0.075 BSC
—
H
—
0.110 BSC
—
L
0.012
0.018
0.024
θ
0°
—
8°
Symbol
A
Rev. 1.20
Dimensions in inch
Dimensions in mm
Min.
Nom.
Max.
—
—
1.45
A1
—
—
0.15
A2
0.90
1.15
1.30
b
0.30
—
0.50
C
0.08
—
0.22
D
—
2.90 BSC
—
E
—
1.60 BSC
—
e
—
0.95 BSC
—
e1
—
1.90 BSC
—
H
—
2.80 BSC
—
L
0.30
0.45
0.60
θ
0°
—
8°
21
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
8-pin SOP (150mil) Outline Dimensions
Symbol
Dimensions in inch
Min.
Nom.
Max.
A
—
0.236 BSC
—
B
—
0.154 BSC
—
0.020
C
0.012
—
C’
—
0.193 BSC
—
D
—
—
0.069
E
—
0.050 BSC
—
F
0.004
—
0.010
G
0.016
—
0.050
H
0.004
—
0.010
α
0°
—
8°
Symbol
Rev. 1.20
Dimensions in mm
Min.
Nom.
Max.
—
A
—
6.0 BSC
B
—
3.9 BSC
—
C
0.31
—
0.51
C’
—
4.9 BSC
—
D
—
—
1.75
E
—
1.27 BSC
—
F
0.10
—
0.25
G
0.40
—
1.27
H
0.10
—
0.25
α
0°
—
8°
22
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
10-pin MSOP Outline Dimensions
Symbol
Min.
Nom.
Max.
A
—
—
0.043
A1
0.000
—
0.006
A2
0.030
0.033
0.037
b
0.007
—
0.013
c
0.003
—
0.009
D
—
0.118 BSC
—
E
—
0.193 BSC
—
E1
—
0.118 BSC
—
e
—
0.020 BSC
—
L
0.016
0.024
0.031
L1
—
0.037 BSC
—
y
—
0.004
—
α
0°
—
8°
Symbol
Rev. 1.20
Dimensions in inch
Dimensions in mm
Min.
Nom.
Max.
A
—
—
1.10
A1
0.00
—
0.15
A2
0.75
0.85
0.95
b
0.17
—
0.33
c
0.08
—
0.23
D
—
3.0 BSC
—
E
—
4.9 BSC
—
E1
—
3.0 BSC
—
e
—
0.5 BSC
—
L
0.40
0.60
0.80
L1
—
0.95 BSC
—
y
—
0.1
—
α
0°
—
8°
23
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
16-pin NSOP (150mil) Outline Dimensions
Symbol
A
Dimensions in inch
Min.
Nom.
Max.
—
0.236 BSC
—
B
—
0.154 BSC
—
C
0.012
—
0.020
C’
—
0.390 BSC
—
D
—
—
0.069
E
—
0.050 BSC
—
F
0.004
—
0.010
G
0.016
—
0.050
H
0.004
—
0.010
α
0°
—
8°
Symbol
Rev. 1.20
Dimensions in mm
Min.
Nom.
Max.
A
—
6.0 BSC
—
B
—
3.9 BSC
—
C
0.31
—
0.51
C’
—
9.9 BSC
—
D
—
—
1.75
E
—
1.27 BSC
—
F
0.10
—
0.25
G
0.40
—
1.27
H
0.10
—
0.25
α
0°
—
8°
24
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
20-pin SOP (300mil) Outline Dimensions
Symbol
Min.
Nom.
Max.
A
—
0.406 BSC
—
B
—
0.295 BSC
—
0.020
C
0.012
—
C’
—
0.504 BSC
—
D
—
—
0.104
E
—
0.050 BSC
—
F
0.004
—
0.012
G
0.016
—
0.050
H
0.008
—
0.013
α
0°
—
8°
Symbol
Rev. 1.20
Dimensions in inch
Dimensions in mm
Min.
Nom.
Max.
—
A
—
10.30 BSC
B
—
7.5 BSC
—
C
0.31
—
0.51
C’
—
12.8 BSC
—
D
—
—
2.65
E
—
1.27 BSC
—
F
0.10
—
0.30
G
0.40
—
1.27
H
0.20
—
0.33
α
0°
—
8°
25
October 17, 2014
BS812A-1/BS813A-1/BS814A-1/BS814A-2
BS816A-1/BS818A-2/BS8112A-3/BS8116A-3
Copyright© 2014 by HOLTEK SEMICONDUCTOR INC.
The information appearing in this Data Sheet is believed to be accurate at the time
of publication. However, Holtek assumes no responsibility arising from the use of
the specifications described. The applications mentioned herein are used solely
for the purpose of illustration and Holtek makes no warranty or representation that
such applications will be suitable without further modification, nor recommends
the use of its products for application that may present a risk to human life due to
malfunction or otherwise. Holtek's products are not authorized for use as critical
components in life support devices or systems. Holtek reserves the right to alter
its products without prior notification. For the most up-to-date information, please
visit our web site at http://www.holtek.com.tw.
Rev. 1.20
26
October 17, 2014