Capacitance detecting device and capacitance detecting method
A capacitance detection and capacitance technology, which is applied in the direction of measuring devices, measuring resistance/reactance/impedance, measuring electrical variables, etc., can solve the problem of increasing the difference in the number of discharge sequences, difficulty suppressing or eliminating noise and circuit noise, and detection sensitivity. and other problems to achieve the effect of preventing impact and stabilizing detection
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
no. 1 example
[0159] Figure 28 It is a specific circuit configuration diagram of the capacitance detecting device 10 related to the first embodiment. In this figure, the input side ( Figure 28 on the left side) is the chopper filter section, which is closer to the output side ( Figure 28 The right side of ) is the integrator 13. The chopper filter section has Figure 10 (a) The chopper filter structure shown.
[0160] Figure 29 is a timing chart of the capacitance detecting device of this embodiment.
[0161] As shown in the figure, SW1 is turned on, and at the same time, SW6, SW11, and SW12 are turned on. By turning on SW1, the capacitance (Cs, Cf) of the input part is charged to Vdd. By turning on SW6 , SW11 , and SW12 at the same time, Cdn is initialized. Similarly, the negative (-) input OP_IN of the operational amplifier 12A is initialized to Vr1 and Cb1 is also initialized. Vr1 is set in consideration of the balance of the input and output voltages of the operational ampli...
no. 2 example
[0184] The second embodiment directly handles the charge distributed by the bipolar drive in a differential manner, and performs the charge transfer timing from the distribution capacitor to the integrator and the charge distribution from the capacitance (Cs, Cf) of the input part to the distribution capacitor in parallel. , implementing a pipeline of two processes.
[0185] Figure 31 is a circuit diagram of the capacitance detecting device according to the second embodiment. The chopper filter is with Image 6 The chopper filter shown in the pipeline structure is basically the same structure. In addition, the basic charge amount canceling mechanism 12 and the integrator 13 and Figure 27 The structure shown is the same. In the capacitance detection device of the second embodiment, the distribution capacitance Cdp1 and the distribution capacitance Cdp2 are distributed in parallel to one pole, and the distribution capacitance Cdn1 and the distribution capacitance Cdn2 are ...
no. 3 example
[0205] In the above first embodiment, if Figure 4 As shown in (a) and (b), the touch sensor module is aimed at the detection of self-capacitance (capacitance between the sensor electrode and GND), but it can also be Figure 4 As shown in (c), a mutual capacitance defined as a difference in capacitance formed between a reference electrode and two sensor electrodes is set as a detection target. Since the detection is performed by differential, it is highly resistant to external common mode noise, and has the advantage of easily canceling the parasitic capacitance (defined as Cs) between the sensor electrode and GND.
[0206] Figure 37 is a circuit configuration diagram of the capacitance detecting device according to the third embodiment. basic structure with figure 2 The embodiment is the same. In the third embodiment, capacitors Cf1 and Cf2 are formed between the drive electrodes (DRV signal) and the differential input section of the detection circuit.
[0207] Figur...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More