BU21010MUV Datasheet, PDF (11/15 Pages) Rohm – Capacitive Sensor Switch Control IC

BU21010MUV
Technical Note
【F7h : Button OFF→ON Threshold】
Name:
TH_ON2
Address:
F7h
Description: A second threshold value for determining a button off→on judgment of sensor.
The sensor output value of 8bit (register SENS_DATA) is compared with
128+ ON2 [6:0], and if it is larger, the button is determined active.
Bit7
F7h
-
R/W
-
Initial val.
-
Bit6
ON2[6]
W
0
Bit5
ON2[5]
W
0
Bit4
ON2[4]
W
1
Bit3
ON2[3]
W
0
Bit2
ON2[2]
W
0
Bit1
ON2[1]
W
0
Bit0
ON2[0]
W
0
【F8h : Button OFF→ON Threshold Selection】
Name:
TH_ON2_CH
Address:
F8h
Description: This register is used to relate either threshold TH_ON or TH_ON2 to particular sensor channels
for button press activity determination.
1 : TH_ON2 is applied 0 :TH_ON is applied
F8h
R/W
Initial val.
Bit7
SIN7
W
0
Bit6
SIN6
W
0
Bit5
SIN5
W
0
Bit4
SIN4
W
0
Bit3
SIN3
W
0
Bit2
SIN2
W
0
Bit1
SIN1
W
0
Bit0
SIN0
W
0
【FAh: Simultaneous Press and Idle Mode Entry】
Name:
CMD
Address:
FAh
Description:
SIMUL_SEL : Simultaneous push judgment element choice ：
In the case of simultaneous key press a decision must be made to select the dominant channel. The chip allows for two
alternative methods. Either it can be based on whichever key press was first, or the priority can be based on the highest
signal level.
1 : A level of a sensor gives priority 0 : Give priority to the channel pushed earliest
INTERMIT_EN : Intermittent and the drive are enable. ：
Whether intermittent is driven at the idol mode is selected.
1：Intermittent is driven. 0：Intermittent is not driven. Initial state：Intermittent is driven.
IDLE_T[3:0] : non-detect time-out setting ：
This sets the time the chip takes to go from normal mode to idle mode in a period key inactivity.
Duration = system clock x 2¹⁹ x IDLE_T (Example of system clock 1[MHz]time : About 520[msec])
Bit7
Bit6
FAh SIMUL_SEL -
R/W
W
-
Initial val.
0
-
Bit5
Bit4
Bit3
- INTERMIT_EN IDLE_T[3]
-
W
W
-
1
0
Bit2
IDLE_T[2]
W
1
Bit1
IDLE_T[1]
W
1
Bit0
IDLE_T[0]
W
1
【FBh : Gain Setting, Filter Function】
Name:
GAIN_FILTER
Address:
FBh
Description: Gain adjustment and setting of noise filter function
GAIN[2:0] : gain setting ：
It uses it for the gain adjustment in eight stages. Initial adjustment value：x1
GAIN[2:0]
000
001
010
011
100 101 110
111
Adjustment value
x 1 x 4.22 x 8.4 x 16.5 x 23 x 46 x 69 x 92
FILTER_EN : Filter enable ：
Enables/disables setting of noise filter function
1 : enabled 0 : disabled Initial state : disabled
DELTA[3:0] : Filter follow count setting ：
The follow count to which the noise filter function is effective is set.
FBh
R/W
Initial val.
Bit7
GAIN[2]
W
0
Bit6
GAIN [1]
W
0
Bit5
GAIN[0]
W
0
Bit4
FILTER_EN
W
0
Bit3
DELTA[3]
W
0
Bit2
DELTA[2]
W
0
Bit1
DELTA[1]
W
1
Bit0
DELTA[0]
W
0
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11/14
2009.04 - Rev.B