US4099074A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Touch sensitive electronic switching circuitry for electronic wristwatches
Assignee: Sharp Corp
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Filing: 1976-03-05
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Granted: 1978-07-04
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Expires: 1996-03-05
Abstract
Abstract In a touch sensitive electronic switching circuit including a C-MOS inverter, for use in an electronic wristwatch, a resistor of about 5 MΩ is connected between the gate electrode of the C-MOS inverter and an input terminal associated with a touch sensitive electrode formed on a preferred position of the casing of the electronic wristwatch. The resistor of about 5 MΩ functions to prevent the C-MOS inverter from being damaged by an erroneous application of a high voltage to the touch sensitive electrode.
Inventors
- 👤 Hidetoshi Maeda
- 👤 Toshihiro Ohba
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 02:59
CPC Classifications
G; G04; G04G; G04G21/00; G04G21/08; H; H03; H03K; H03K17/00; H03K17/94; H03K17/96; H03K17/9645
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
162 words
A touch sensitive electronic switching circuit for electronic wristwatches including a C-MOS inverter having a gate electrode, a pair of source electrodes, and a drain electrode, first and second input terminals for said C-MOS inverter across which an operator's body completes an electrical circuit to initiate switching of said C-MOS inverter from one state to another, a bias voltage source coupled to at least one of said source electrodes and to one of said first and second input terminals through a first resistor means, the other of said first and second input terminals being directly coupled to the other of said source electrodes, a gate protective circuit coupled between said gate electrode and the respective source electrodes, wherein the improvement comprises: second resistor means in the gate circuit of said C-MOS inverter coupled between said first resistor means and said gate protective circuit for preventing damage to said gate protective circuit from an erroneous application of high voltage to said input terminals.
Claim 2
Dependent Claim
162 words
A touch sensitive electronic switching circuit for electronic wristwatches including a C-MOS inverter having a gate electrode, a pair of source electrodes, and a drain electrode, first and second input terminals for said C-MOS inverter across which an operator's body completes an electrical circuit to initiate switching of said C-MOS inverter from one state to another, a bias voltage source coupled to at least one of said source electrodes and to one of said first and second input terminals through a first resistor means, the other of said first and second input terminals being directly coupled to the other of said source electrodes, a gate protective circuit coupled between said gate electrode and the respective source electrodes, wherein the improvement comprises: second resistor means in the gate circuit of said C-MOS inverter coupled between said first resistor means and said gate protective circuit for preventing damage to said gate protective circuit from an erroneous application of high voltage to said input terminals.
Claim 3
Dependent Claim
22 words
The touch sensitive electronic switching circuitry of claim 1, wherein said second resistor means has a resistance value of about 4.7 MΩ.
Claim 4
Dependent Claim
26 words
The touch sensitive electronic switching circuitry of claim 1, wherein one of said input terminals is formed on a front glass window of the electronic wristwatch.
Claim 5
Dependent Claim
28 words
The touch sensitive electronic switching circuit of claim 1, wherein said bias voltage source is at a negative potential and said other of said source terminals is grounded.
Claim 6
Dependent Claim
69 words
The touch sensitive electronic switching circuitry of claim 4, wherein the gate protective circuit comprises: a third resistor disposed between the gate electrode of the C-MOS inverter and said second resistor means; two diodes respectively disposed between the grounded terminal and the respective ends of the third resistor; and another diode disposed between the gate electrode of the C-MOS inverter and the source terminal coupled to said bias voltage.
Claim 7
Dependent Claim
28 words
The touch sensitive electronic switching circuit of claim 1, wherein said bias voltage source is at a positive potential and said other of said source terminals is grounded.
Claim 8
Dependent Claim
48 words
The touch sensitive electronic switching circuit of claim 6, wherein there is further provided a capacitor means coupled between said bias voltage source and a point in the gate circuit of said C-MOS inverter, said point being disposed between said second resistor means and said gate protective circuit.
Claim 9
Dependent Claim
65 words
The touch sensitive electronic switching circuitry of claim 6, wherein the gate protective circuit comprises: a third resistor disposed between the gate electrode of the C-MOS inverter and said second resistor means; two diodes disposed between the bias voltage source and the respective ends of the third resistor, respectively; and another diode disposed between the gate electrode of the C-MOS inverter and the grounded terminal.
Claim 10
Dependent Claim
36 words
The touch sensitive electronic switching circuit of claim 8, wherein there is further provided a capacitor means coupled between said bias voltage source and a junction point between said second resistor means and said third resistor.
Claim 11
Dependent Claim
57 words
The touch sensitive electronic switching circuit of claim 9, wherein the cathodes of said two diodes are coupled to said bias voltage source and the anodes are coupled to the respective ends of said third resistor, and said another diode has the cathode thereof coupled to said gate electrode and the anode coupled to said grounded electrode.
Claim 12
Dependent Claim
22 words
The touch sensitive electronic switching circuit of claim 6, wherein said second resistor means has a resistance value of about 4.7 MΩ.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-07-03 | 1982-01-02 | 1982-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-03 | 1986-01-02 | 1986-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-03 | 1990-01-02 | 1990-07-04 | $7700.00 | Window Closed / Lapsed |