Memory cell voltage regulator with temperature correlated voltage generator circuit

A regulator for a drain voltage of a single-supply memory cell, comprising;

• a differential stage having an inverting input terminal receiving a control voltage independent of temperature, a non-inverting input terminal connected to a ground voltage reference (GND), and an output terminal connected to the non-inverting input terminal;
• a booster circuit connected to said output terminal and to a supply terminal of tile differential stage, said supply terminal being feedback connected to the output terminal and receiving a boosted voltage (Vpump) from the booster circuit;
• and
• a temperature-related voltage generating circuit, comprising an input terminal receiving a control voltage independent of temperature, an output terminal delivering a temperature-related control voltage, said input and output terminals being connected together through at least an amplifier stage adapted to set an output reference voltage from a comparison of input voltages;
• a generator element generating a varying voltage with temperature connected between a ground voltage reference and a non-inverting input terminal of said amplifier stage, which has an output terminal adapted to deliver a multiple of the varying voltage with temperature to an inverting input terminal of a comparator stage;
• said comparator stage has an output terminal connected to the output terminal of the temperature-related voltage generating circuit and a non-inverting input terminal receiving said control voltage independent of temperature to evaluate a difference between the control voltage independent of temperature and said voltage being a multiple of the varying voltage with temperature and to output said temperature-related control voltage which has at room temperature a mean value which is independent of said temperature-related control voltage thermal differential and increases with temperature, said temperature-related voltage generating circuit being adapted to supply a temperature-related control voltage to the inverting input terminal of the differential stage such that a secondary program voltage is obtained for the memory cell at a constant value, at room temperature, the regulator enabling an adjustment to be made of an average increase of a voltage drop across a column decoder connected to the memory cell by means of an equivalent increase in the secondary program voltage, thereby ensuring invariance of a drain voltage of the memory cell with temperature.

A circuit, comprising:

• an input terminal receiving a temperature-independent control voltage;
• an output terminal delivering a temperature-dependent output voltage;
• a voltage generator coupled to the input terminal and structured to produce a temperature-dependent voltage reference signal;
• and
• a comparator having first and second input terminals and an output terminal, the first input terminal being coupled to the input terminal of the circuit, the second input terminal being coupled to the voltage generator and the comparator output terminal being coupled to the output terminal of the circuit, the comparator being structured to compare the control voltage to the reference voltage and produce the output voltage based on the comparison.

A method of providing a temperature-dependent output voltage, the method comprising:

• receiving a temperature-independent control voltage;
• generating a temperature-dependent reference voltage;
• comparing the reference voltage to the control voltage;
• and
• producing the temperature-dependent output voltage based on the comparising wherein the output voltage is substantially equal to the control voltage at room temperature.