Claims
- 1. A storage circuit for storing an electrical signal, comprising
- an electronic switch,
- a capacitor connected to be charged by the electrical signal through the electronic switch,
- the switch being capable of assuming a high impedance state to minimise subsequent discharge of the capacitor,
- a pair of voltage supply lines,
- a field effect transistor having an input circuit connected to receive the charge on the capacitor and having an output circuit,
- a variable impedance device,
- the output circuit of the field effect transistor being connected across the voltage supply lines in series with the variable impedance device,
- means responsive to the voltage across the voltage supply lines for controlling the variable impedance device so that the current in the output circuit of the field effect transistor is substantially constant at a predetermined value, and
- means connected to the output circuit of the field effect transistor to derive an output signal of the storage circuit in dependence on the charge on the capacitor,
- the said predetermined value of the current being the current value at which the variation of the conductivity of the field effect transistor with temperature is substantially a minimum.
- 2. A storage circuit according to claim 1, in which the electronic switch is a further field effect transistor.
- 3. A circuit according to claim 1, in which the gain of the field effect transistor is such that the relationship between the output signal and the charge on the capacitor varies with the charge on the capacitor.
Parent Case Info
This is a division of application Ser. No. 774,865, filed Mar. 7, 1977, now U.S. Pat. No. 4,196,466.
US Referenced Citations (3)
Divisions (1)
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Number |
Date |
Country |
Parent |
774865 |
Mar 1977 |
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