BU21008MUV Datasheet, PDF (14/17 Pages) Rohm – Capacitive Sensor Switch Control IC

BU21008MUV
Technical Note
【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
x1
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
【FCh : Switch OFF -> ON Threshold】
Name:
TH_ON
Address:
FCh
Description: This register provides a threshold value for determining if a sensor has transitioned from OFF to ON.
This is relative value from reference value (128d). So the absolute value of threshold is 128d+ON[6:0].
It makes a threshold value between TH_ON and TH_OFF.
TH_ON must be bigger than TH_OFF (TH_ON >= TH_OFF)
Maximum threshold is 256d and minimum value is 128d.
Bit7
FCh
-
R/W
-
Initial val.
-
Bit6
ON[6]
W
0
Bit5
ON[5]
W
0
Bit4
ON[4]
W
1
Bit3
ON[3]
W
0
Bit2
ON[2]
W
0
Bit1
ON[1]
W
0
Bit0
ON[0]
W
0
【FDh : Switch ON -> OFF Threshold Value】
Name:
TH_OFF
Address:
FDh
Description: This register provides a threshold value for transitioning from ON to OFF.
This is relative value from reference value (128d). So absolute value of threshold is 128d+OFF[6:0].
It makes a threshold value between TH_ON and TH_OFF.
TH_OFF must be smaller than TH_ON (TH_OFF =< TH_ON)
Maximum value is 256d and minimum value is 128d.
Bit7
FDh
-
R/W
-
Initial val.
-
Bit6
OFF[6]
W
0
Bit5
OFF[5]
W
0
Bit4
OFF[4]
W
0
Bit3
OFF[3]
W
0
Bit2
OFF[2]
W
0
Bit1
OFF[1]
W
0
Bit0
OFF[0]
W
1
【FEh : LED Port Data】
Name:
DLED
Address:
FEh
Description: When LED is not linked with the sensor, it becomes a simple digital output that controls the LED.
1 : Light. 0 : Turned off.
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
FEh
D7
D6
D5
D4
D3
D2
D1
D0
R/W
W
W
W
W
W
W
W
W
Initial val.
0
0
0
0
0
0
0
0
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14/16
2009.04 - Rev.B