JPH0391015A - Internal circuit operation speed control circuit for semiconductor device - Google Patents

Abstract

PURPOSE:To set a proper operation speed to prevent the increase of power consumption by providing a circuit, which controls the internal circuit operation speed, between a power input terminal and an internal power line. CONSTITUTION:An internal circuit operation speed control circuit 16 is provided between an input terminal 10 and an internal power supply line 14 for power supply to a processing circuit 12. That is, resistances 18A and 18B which divide the source voltage applied from the input terminal 10, a comparator 20, a circuit 22 which generates a reference voltage Vref, and a transistor 24 which controls the voltage transmitted to the internal power supply line 14 in accordance with the output difference signal of the comparator are provided. The reference voltage generating circuit 22 generates the desired reference voltage Vref, and the supply voltage is set to zero when the reference voltage is set to zero. Thus, the operation speed is controlled to a not too high but proper value to prevent the increase of power consumption.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to an internal circuit operation speed control circuit for a semiconductor device, which is suitable for adjusting the processing speed and power of the semiconductor device to appropriate levels.

[Conventional technology]

Conventionally, semiconductor devices, such as complementary engraving R oxide film semiconductors (
In a CMO3), a voltage of, for example, 3 to 6 V is applied and supplied to its internal circuit from an external power supply via an internal ti line. By the way, if the voltage of this power supply is higher than necessary,
Depending on the semiconductor device, the processing speed of the internal circuit of the semiconductor device becomes faster than necessary, and the power consumption increases.In some cases, it is not desirable for the power consumption to increase.

[Problem to be achieved by the invention]

However, in the past, there was no technology to control the voltage of the internal circuit of a semiconductor device to an appropriate value for the purpose of controlling the internal circuit operating speed, so the processing speed became faster than necessary and power consumption increased. The problem was that it could not be prevented. SUMMARY OF THE INVENTION An object of the present invention is to provide an internal circuit operating speed control circuit for a semiconductor device that can appropriately control the internal circuit operating speed of a semiconductor device and prevent an increase in power consumption.

[Means to achieve the task]

The present invention achieves the above object by providing a circuit for controlling the operating speed of an internal circuit of a semiconductor device between a power supply input terminal and an internal power supply line of the semiconductor device.

[Effect]

In the present invention, in a semiconductor device, a circuit for controlling the internal circuit operating speed of the semiconductor device is provided between a power input terminal of the semiconductor device and an internal power supply line. Therefore, since the internal circuit operating speed of the semiconductor device can be controlled to an appropriate value, the operating speed can be controlled to an appropriate value that does not become too high, and an increase in power consumption can be prevented. Furthermore, since the processing speed can be reduced to an appropriate value, noise generated from the semiconductor device can be reduced.

【Example】

Embodiments of the present invention will be described in detail below with reference to the drawings. First, a first example will be described. In this first embodiment, in a semiconductor device, as shown in FIG. An operating speed control circuit 16 for controlling the operating speed of the processing circuit 12 by controlling the supply voltage to the processing circuit 12 is provided between the internal power supply line 14 for supplying the processing circuit 12 (equivalent to 12). be. As shown in FIG. 1, this operating speed control circuit 16 includes:
resistors 18A and 18B for dividing the power supply voltage applied from the input terminal 10; a comparator 20 for comparing the divided voltage with a reference voltage Vref serving as a control target; and outputting a difference signal; A circuit 22 for generating a reference voltage Vref and a transistor 24 for controlling the voltage transmitted to the internal power supply line 14 according to the output difference signal of the comparator 20 are provided. The reference voltage generation circuit 22 generates a desired reference voltage Vref.
If the reference voltage is set to zero, the supply voltage can be set to zero. In the operating speed control circuit 16 according to the first embodiment, first, the power supply voltage Vdd applied from the input terminal 10 is divided by the resistors 18A and 18B, and the divided voltage is compared with the reference voltage V ref by the comparator 20. Then, a difference signal based on the comparison result is input to the transistor 24, and the transistor 24 controls the voltage supplied to the internal power supply line 14 so that the supplied voltage is set to the reference voltage V ref
Control according to the following. By controlling the supply voltage in this manner, the processing speed of the semiconductor processing circuit 12 can be controlled, thereby reducing power consumption and noise generated. Note that if the voltage supply is not required, the reference voltage Vref is set to zero and the supply is stopped. Next, a second example will be described. In this second embodiment, as shown in FIG. 2, a second operating speed control circuit 26 is provided in place of the operating speed control circuit 16 of the first embodiment. The second operating speed control circuit 26 mainly includes a second reference voltage generation circuit 28, a second comparator 30 that compares the reference voltage Vref from the generation circuit 28 and the input voltage Vdd, and A second control transistor 32 for controlling the power supply voltage by the output of 30 is provided. The reference voltage generating circuit 28 includes a variable resistor 34 for adjusting the voltage supplied to the processing circuit 12, an integrating circuit 36 consisting of a capacitor C and a resistor R, and an oscillator, for example, that outputs a pulse signal of a predetermined frequency. It has an oscillation circuit 38 consisting of. Note that the oscillation frequency of the oscillation circuit 38 changes depending on the voltage of the processing circuit 12, that is, the voltage of the internal power supply line 14, and as the voltage of the internal power supply line 14 increases, the oscillation frequency increases, and the output of the integrating circuit 36 increases. The voltage (reference voltage vref) becomes higher. Then, negative feedback is applied to the second comparator 30,
The second control transistor 32 is controlled to lower the potential of the internal power supply line 14. In this way, the oscillation port FI&38 has the function of keeping the potential of the power supply line 14 at a constant value. In this second embodiment, first, by changing the variable resistor 34 of the second reference voltage generation circuit 28, the reference voltage Vref output from the oscillation circuit 38 and the integration circuit 36 is
is controlled and input to the second comparator 30. This second comparator 30 compares the power supply voltage Vdd and the reference voltage Vref, and controls the second control transistor 32 according to the difference. As a result, the voltage supplied to the internal power supply line 14 becomes a voltage controlled by the reference voltage V ref specified by the variable resistor 34 . Therefore, by adjusting the variable resistor 34, the voltage supplied to the semiconductor processing circuit 12 can be controlled, so that the processing speed can be prevented from increasing too much, power consumption can be prevented from increasing, and generated noise can be reduced. In addition, in the first and second embodiments, the operating speed control circuits 16 and 26 as shown in FIGS. Any other operating speed control circuit may be used as long as the operating speed of the internal power supply line can be controlled, for example, by the supply voltage.

【Effect of the invention】

As described above, according to the present invention, since the internal circuit operating speed can be controlled using, for example, an internal voltage, the processing speed of the semiconductor device can be controlled so as not to become too fast, and the extinction force can be reduced. Furthermore, since the processing speed is reduced, excellent effects such as reduction in noise generated such as spikes can be obtained.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing the configuration of an internal circuit operation speed control circuit according to a first embodiment of the present invention, and FIG.
FIG. 2 is a circuit diagram showing the configuration of an internal circuit operation speed control circuit according to an embodiment. 8... Power supply, 9... Semiconductor device, 10... Input terminal, 12... Semiconductor processing circuit, 14... Internal power supply line, 16... Internal circuit operating speed control circuit, 18A, 18B
...Voltage dividing resistor, 20... Comparator, 22... Reference voltage generation circuit, 24... Control transistor, 26... Second internal circuit operating speed control circuit, 28...
- Second reference voltage generation circuit, 0... Second comparator, 2... Second control transistor, 4... Variable resistor, 6... Integrating circuit, 8... Oscillating circuit.

Claims (1)

[Claims] (1) Internal circuit operation speed control of a semiconductor device, characterized in that a circuit for controlling the internal circuit operation speed of the semiconductor device is provided between a power input terminal and an internal power supply line of the semiconductor device. circuit.