B6TS-08NF Omron, B6TS-08NF Datasheet - Page 25

• Manufacturer Part Number: B6TS-08NF
• Description: Capacitance Touch Sensors Sensing IC
• Manufacturer: Omron
• Series: -r
• Type: Capacitiver

Specifications of B6TS-08NF

• Supply Voltage: - 0.3 V to 6.5 V
• Number Of Channels: 8
• Dimensions: 9 mm L x 9 mm W x 1.7 mm H
• Output Voltage: -0.3 V to Vsupply + 0.3 V
• Power Dissipation: 300 mW
• Temperature Range: - 20 C to + 85 C
• Termination Style: SMD/SMT
• Sensitivity: -
• Response Time: -
• Interface: SPI
• Channel Inputs: 8 Key
• Voltage - Supply: 4.5 V ~ 5.5 V
• Actuator Type: -
• Package / Case: 32-QFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

7.2
To perform teaching, this chip must be brought into setup mode and some parameters must be set.
The parameters (commands) associated with teaching are as follows:
7.2.1
7.2.2
7.2.3
7.2.4
Preparation for teaching
During teaching, measurement is executed x number of times where x is the value of this parameter × 32.
(Hereafter, this is referred to as the teaching measurement count)
It takes 30–100 msec for one teaching measurement (depending on external circuit constants), and if this
parameter is set to 10, the touches must be executed within 10-30 seconds.
Unless each electrode is touched three times within the number of teaching measurements after starting teaching,
the teaching is regarded as faulty, and none of the parameters are updated.
However, when this parameter is set to "0", only the reference value (REFx) is updated. In this case, no touching
is required, and the teaching is not regarded as faulty even if no touches are executed.
This parameter contains the quantity of variation of the measured value that will allow judgment of a touch
(approximate value).
To distinguish between variation of the measured value caused by a noise or the like and variation caused by
touching during teaching, this parameter must be set to an approximate value.
If variation of half of this set value occurs during teaching, the electrode is judged touched. Therefore, an
approximate value for variation likely to have been caused by touch may be entered.
This parameter sets the hysteresis value in teaching (approximate value).
Hysteresis ratio (Refer to “6.2.17 RHYSx: Hysteresis ratio for each channel”)
These parameters set the ratios of the quantity of judging change (THRx) and hysteresis (HYSx) to the variation
of the measured value caused by touch.
During teaching, each electrode must be touched three times or more. Then, the minimum value of the quantity of
variation caused by touch is calculated for each electrode of the chip. (Minimum value of quantity of variation)
The new quantity of judging change and the new hysteresis are calculated using the minimum value of quantity of
variation ΔA as:
Teaching measurement count (Refer to "6.2.8 TCAL: Teaching measurement count")
On-judgment ratio (refer to "6.2.15 THRx: On-judgment ratio for each channel”)
Hysteresis ratio (Refer to “6.2.16 HYSx: Hysteresis ratio for each channel”)
On-judgment ratio (Refer to “6.2.17 RTHRx: On-judgment ratio for each channel”) and
Quantity of judging change (THRx) = ΔA×(On-judgment ratio (RTHRx)+1)/16
Hysteresis (HYSx) = ΔA×(Hysteresis ratio (RHYSx))/16
Measured
value
Figure 10 . teaching parameter setting
Touch on
electrode
25
Time
(On-judgment ratio [RTHRx] + 1) / 16
(Hysteresis ratio [RHYSx]) / 16
3713050-2A Ver.080123