JPS61111004A - Oscillation circuit - Google Patents

Abstract

PURPOSE:To attain low power consumption at oscillation by conducting a P- channel and an N-channel MOSFET at oscillation start in the oscillation circuit consisting of complementary MOSFETs so as to decrease the oscillation start time. CONSTITUTION:Since a front gate comprising the P-channel MOSFET6 and the N-channel MOSFET7 is turned on/off by an input signal impressed to an input terminal In2, when a high level signal is given to the input terminal I22 at impression of power, the FETs 6, 7 are turned on to short-circuit resistors 1, 2. Thus, substrate bias effect is lost to the resistors 1, 2 and the oscillation stable time is reduced. When the oscillating state is stable and a low level signal is given to the input terminal I22, the FETs 6, 7 are turned off, and the resistors 1, 2 connected to the source of the P-channel MOSFET4 and the N-channel MOSFET5 increase the absolute value of each threshold voltage at the transition region due to the substrate bias effect so as to reduce power consumption at oscillation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an oscillation circuit, and more particularly to an oscillation circuit constituted by complementary MO8FETs.

[Conventional technology]

Complementary MO8FET conventionally used in electronic watches, etc.
The oscillation circuit configured with the above has a long time to stabilize after power is applied, that is, it takes a long time to start oscillation, and during the manufacturing process, time is wasted adjusting the oscillation frequency during circuit operation inspection. On the other hand, as the lifespan of electronic watches has been lengthened, the power consumption of L-oscillation circuits has been reduced, and the oscillation start time is becoming longer and longer.

An example of a conventional oscillation circuit! The input end of the oscillation circuit shown in FIG. 2 is connected to the front gate of the P-channel MO8FET4, the front gate of the N-channel MO8FET5, and one end of the resistor 3.

The source of the P-channel MO8FET4 is connected via the resistor 1, and the back gate is directly connected to the power supply vDD. The source of the N-channel MO8FET5 is connected via the resistor 2, and the back gate is directly connected to the power supply Vs s (=
OV) Double H Shite Its Lou P f Janne/
'The drain of MO8FET4 is N-channel MO8FE
It is connected to the drain of T5 and the other end of the resistor 3, respectively, and this connection point is assumed to be the output terminal 0utl of the total oscillation circuit.

Input terminal In1. A 9-karat gold crystal oscillator is connected between the output terminal 0UTI.

In the conventional oscillation circuit connected as above, P
08FE between channel MO8FET4 and N channel
Resistor 1 connected to each source side of 'l'5
, 2 is a transition region (P-channel MO8FET4 or N-channel MO8FET 1 (J8
This is an effective means of reducing power consumption during oscillation by increasing the absolute value of each threshold voltage in the region where FET 5 is ON, but it takes a long time to stabilize oscillation when power is applied. It has a drawback.

[Problems to be Solved by the Invention] An object of the present invention is to provide an oscillation circuit that has a short oscillation start time and consumes low power during oscillation.

[Rounding method to solve problems]

According to the present invention, the first resistor, the first P-channel MO
Between the source and drain of 8FET, the first N-channel M
An amplifier configured by connecting the source and drain of an O8FET and a second resistor in series, and the input and output terminals of this amplifier.
A nine feedback circuit including an oscillation element is connected between the outputs, and a first
A second P-channel MO8FET whose source and drain are connected in parallel to the resistor, and a source and drain connected to the second resistor.
a second N-channel MO whose drains are connected in parallel;
An oscillation circuit is obtained having a second P-channel MO8FET and a second P-channel MO8FET and means for making the N-channel MO8FET conductive at the start of oscillation.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to all drawings.

Figure 1 shows an embodiment of the present invention, and the same parts as in Figure 2 are given the same reference numerals. The conventional circuit shown in FIG. Channel MO8
It is connected to the front gate of FET7 and the input of Inburn 80, and the output of inverter 8 [P channel MO8F
Connected to the front gate of ET6. P-channel MO8FET6 (7) source and back gate are connected to power supply vDD and drain is P-channel MO8FET4
N-channel MO8FE
The source and back gate of T7 are connected to the power supply V3. (=OV
) connected to the drain 1jN channel MO8F
Connected to the source of ET5.

In one embodiment of the present invention, the P-channel MO
The front gates of 8FET6 and N-channel MO8FET7 are turned ON and OFF by the input signal applied to the input chain n2, so when power is applied, the front gates of the N-channel MO8FET7 apply a high voltage to the signal applied to the input chain n2. When this is applied, P-channel MO-8FET6 and N-channel MO8FET7 are turned on, shorting both ends of resistor 1.2. This eliminates the aforementioned substrate bias effect on the machined resistors 1 and 2, making it possible to shorten the time required for oscillation to stabilize.

When the excavation state became stable, Eri and P applied a low level (low voltage as potential) to the input terminal In2.
Channel MO8FET6 and N channel MO8
FET7 turns OFF and P channel N illusion-8 FET4
A resistor 1.2 connected to the source side of each of the N-channel MO8FETs 5 and 5 is connected to the absolute fiitt of each threshold voltage in the LD transition region due to the body bias effect.
- It is possible to increase the cost and reduce power consumption during @flea operation.

〔Effect of the invention〕

As described above, if the present invention is implemented, it is possible to shorten the time until oscillation stabilization and reduce power consumption, which has great effects.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram according to an embodiment of the present invention, and FIG. 2 is a circuit diagram of a conventional oscillation circuit. 1, 2.3... Resistor, 4.6... P channel M (JSFET, 5. 7... N channel MO8FET. 8... Inverter, ■.1 ,1n2...Input terminal, Uutl...Output terminal, 9...
Crystal oscillator. Agent Patent Attorney Susumu Uchihara'；ゞ-'7゛＼(
r, x21

Claims (1)

[Claims] The first resistor, the source-drain of the first P-channel field effect transistor, the drain-source of the first N-channel field-effect transistor, and the second resistor are connected in series, and the first P-channel field effect transistor is connected in series with the second resistor. an amplifier whose input terminal is the common connection point of the gates of the channel and N-channel field effect transistors, and whose output terminal is the common connection point of the drains of the P-channel and N-channel field effect transistors; and an oscillation element between the input and output terminals of the amplifier. a second P-channel field effect transistor connected in parallel to the first resistor;
An oscillation circuit comprising: a second N-channel field effect transistor connected in parallel to the resistor; and means for rendering the second P-channel and N-channel field effect transistors conductive at the start of oscillation.