An ultra-low power consumption driving circuit

Abstract

The present invention discloses an ultra-low power consumption driving circuit, and relates to the technical field of integrated circuits. The driving circuit includes a starting module, an oscillator module and an output module, a power supply module and a current switching module; the starting module and the power supply module are connected to the oscillator module through the current switching module, and the oscillator module is connected to the output module; the current switching module is connected to the starting module to provide a starting current for the oscillator module, so that the oscillator module starts working and outputs an oscillation signal; after the oscillator module starts working, the current switching module is connected to the power supply module to provide a working current for the oscillator module, and the starting module is cut off; the output module is used to amplify and output the oscillation signal. The technical solution of the present invention is to connect the power supply module to provide a working current for the oscillator module after the oscillator module starts working, and at the same time cut off the starting module, so as to provide an extremely low power consumption crystal driving circuit.

Description

Technical Field

[0001] The invention relates to an integrated circuit, and in particular to an ultra-low power consumption driving circuit. Background Art

[0002] Since the advent of crystal drivers in the 1920s, their theoretical research and manufacturing levels have developed rapidly, and various performance indicators have been significantly improved. As a clock frequency source, compared with other types of oscillators, crystal oscillators are widely used in military and civilian consumer electronics fields with their excellent Q value, frequency accuracy, stability, etc. In the field of integrated circuits, in order to effectively and reasonably transmit the crystal frequency signal to the chip core, the role of IO interface integrated circuits is crucial. With the increasing requirements for the performance of crystal drive circuits, low-power or even extremely low-power 32.768K crystal drive circuits have always been the direction of IO designers' efforts.

[0003] In the prior art, there are two types of low-power crystal drive circuits:

[0004] First, when the circuit needs to work, a large current is connected to make the 32.768K crystal oscillator work stably; however, the large current will increase the power consumption of the circuit and fail to achieve the purpose of low power consumption;

[0005] Second, when the circuit needs to work, after the 32.768K crystal oscillator is started by connecting a large current, the negative feedback circuit is used to adjust the working current to reduce the working current in the circuit; however, the working current reduced by such adjustment is small and cannot meet the circuit's extremely low power consumption requirement, and increases the circuit startup time. Summary of the invention

[0006] The main purpose of the present invention is to provide an ultra-low power consumption driving circuit, aiming to reduce the power consumption of a 32.768K crystal driving circuit.

[0007] To achieve the above-mentioned purpose, the present invention provides an ultra-low power consumption driving circuit, comprising a starting module, an oscillator module and an output module, the driving circuit also comprising a power supply module and a current switching module; the starting module and the power supply module are connected to the oscillator module through the current switching module, and the oscillator module is connected to the output module; the current switching module turns on the starting module to provide a starting current for the oscillator module, so that the oscillator module starts working and outputs an oscillation signal; after the oscillator module starts working, the current switching module turns on the power supply module to provide a working current for the oscillator module and cuts off the starting module; the output module is used to amplify and output the oscillation signal.

[0008] Preferably, the startup module provides a startup current of 200 nA-5 μA to the oscillator module.

[0009] Preferably, the starting current is 300nA.

[0010] Preferably, the power supply module provides the oscillator module with an operating current of 50 nA to 80 nA.

[0011] Preferably, the operating current is 60 nA.

[0012] Preferably, the current switching module includes a first transmission gate connected to the startup module and a second transmission gate connected to the power supply module, the first transmission gate is connected to the switching signal input end, and the second transmission gate is connected to the switching signal input end through a first inverter; the first transmission gate and the second transmission gate respectively receive the switching signal to respectively turn on / off the startup current and the working current.

[0013] Preferably, the startup module includes a second inverter, a first PMOS tube, a second PMOS tube, a third PMOS tube, a fourth PMOS tube, a fifth PMOS tube, a first NMOS tube, a second NMOS tube, a third NMOS tube, a fourth NMOS tube, a fifth NMOS tube, a sixth NMOS tube and a first resistor; the input ends of the first PMOS tube, the first NMOS tube and the second inverter are connected to the startup signal input end; the second PMOS tube is connected to the output end of the second inverter, the third PMOS tube, the fourth PMOS tube and the fifth PMOS tube are connected to the second PMOS tube; the second NMOS tube is connected to the first PMOS tube; the third NMOS tube is connected to the third PMOS tube, the fourth NMOS tube and the fifth NMOS tube; the sixth NMOS tube is connected to the first PMOS tube and the first NMOS tube; the first resistor is connected to the fifth NMOS tube.

[0014] Preferably, the gate of the first PMOS tube and the gate of the first NMOS tube are connected to the start signal input terminal; the source of the first PMOS tube is connected to the power supply, and the drain of the first PMOS tube is connected to the drain of the first NMOS tube, the gate of the second NMOS tube and the drain of the sixth NMOS tube; the source of the first NMOS tube and the sixth NMOS tube is grounded; the source of the second PMOS tube, the third PMOS tube, the fourth PMOS tube and the fifth PMOS tube is connected to the power supply; the gate of the second PMOS tube is connected to the output terminal of the second inverter, and the drain is connected to the drain of the second NMOS tube; the gates of the third PMOS tube, the fourth PMOS tube and the fifth PMOS tube are connected to each other and connected to the The drain of the second PMOS tube; the drain of the fifth PMOS tube is connected to the current switching module to output a startup current for the current switching module; the sources of the second NMOS tube, the third NMOS tube and the fourth NMOS tube are grounded; the drain and the gate of the third NMOS tube are connected to each other and to the drain of the third PMOS tube; the gate of the fourth NMOS tube is connected to the gate of the first NMOS tube and the startup signal input terminal, and the drain is connected to the gates of the third NMOS tube, the fifth NMOS tube and the sixth NMOS tube; the drain of the fifth NMOS tube is connected to the drain of the fourth PMOS tube, and the source is connected to one end of the first resistor, and the other end of the first resistor is connected to the gate of the first NMOS tube and the startup signal input terminal.

[0015] Preferably, the output module includes a first capacitor, a third inverter, a fourth inverter and a fifth inverter connected in sequence, the first capacitor is also connected to the oscillator module; the output end of the third inverter is also connected to its input end; the fifth inverter outputs the amplified oscillation signal to the subsequent circuit.

[0016] The technical solution of the present invention uses a current switching module to connect a power supply module to provide working current for the oscillator module after the oscillator module starts working, and simultaneously cuts off the start-up module to provide a crystal drive circuit with extremely low power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the circuit structure of the ultra-low power consumption driving circuit according to an embodiment of the present invention.

[0018] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0019] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0020] The present invention is further described below in conjunction with the accompanying drawings.

[0021] The embodiment of the present invention provides an ultra-low power consumption driving circuit, which is used to drive a 32.768K crystal oscillator so that the oscillator can work stably with extremely low power consumption.

[0022] like Figure 1 As shown, the ultra-low power consumption driving circuit of the embodiment of the present invention includes a starting module, an oscillator module and an output module, and the driving circuit also includes a power supply module and a current switching module; the starting module and the power supply module are connected to the oscillator module through the current switching module, and the oscillator module is connected to the output module; the current switching module turns on the starting module to provide the starting current I1 for the oscillator module, so that the oscillator module starts working and outputs an oscillation signal; after the oscillator module starts working, the current switching module turns on the power supply module to provide the oscillator module with a working current I2, and cuts off the starting module; the output module is used to amplify and output the oscillation signal.

[0023] Preferably, if Figure 1 As shown, the current switching module includes a first transmission gate connected to the startup module and a second transmission gate connected to the power supply module, the first transmission gate is connected to the switching signal input terminal I_sel, and the second transmission gate is connected to the switching signal input terminal I_sel through a first inverter N1; the first transmission gate and the second transmission gate respectively receive switching signals to respectively turn on / off the startup current I1 and the operating current I2.

[0024] In a specific embodiment, the switching signal input terminal I_sel is connected to a register, and the switching signal is configured for the current switching module through the register. The first transmission gate is connected to the switching signal input terminal I_sel, and the second transmission gate is connected to the switching signal input terminal I_sel through the first inverter N1, so that when the first transmission gate is turned on, the second transmission gate is turned off, and when the first transmission gate is turned off, the second transmission gate is turned on.

[0025] Specifically, when the oscillator module needs to be started, the first transmission gate is turned on and the second transmission gate is turned off so that the starting current I1 powers the oscillator module; after the oscillator module is started for 1 second, the first transmission gate is turned off and the second transmission gate is turned on so that the working current I2 powers the oscillator module.

[0026] In a specific embodiment, the power supply module can be an external current source. The power supply module provides the oscillator module with a working current I2 of 50nA to 80nA. The preferred working current I2 is 60nA, and can also be 50nA, 55nA, 65nA, or 70nA. A smaller working current can greatly reduce the power consumption in the circuit to achieve extremely low power consumption of the circuit.

[0027] Preferably, if Figure 1 As shown, the startup module includes a second inverter N2, a first PMOS tube PM1, a second PMOS tube PM2, a third PMOS tube PM3, a fourth PMOS tube PM4, a fifth PMOS tube PM5, a first NMOS tube NM1, a second NMOS tube NM2, a third NMOS tube NM3, a fourth NMOS tube NM4, a fifth NMOS tube NM5, a sixth NMOS tube NM6 and a first resistor R1; the input ends of the first PMOS tube PM1, the first NMOS tube NM1 and the second inverter N2 are connected to the startup signal input end PD_HV; the second PMOS tube PM2 connected to the output end of the second inverter N2, the third PMOS tube PM3, the fourth PMOS tube PM4 and the fifth PMOS tube PM5 are connected to the second PMOS tube PM2; the second NMOS tube NM2 is connected to the first PMOS tube PM1; the third NMOS tube NM3 is connected to the third PMOS tube PM3, the fourth NMOS tube NM4 and the fifth NMOS tube NM5; the sixth NMOS tube NM6 is connected to the first PMOS tube PM1 and the first NMOS tube NM1; the first resistor R1 is connected to the fifth NMOS tube NM5.

[0028] In a specific embodiment, the start signal input terminal PD_HV can be connected to a register to configure the start signal, or can be configured through an external pad. When the oscillator module needs to be started, a start signal is input to enable the circuit to generate a start current I1 for starting the oscillator module.

[0029] When the oscillator module works stably, the switching module connects the power supply module to the oscillator module so that the power supply module provides a stable working current I2 for the oscillator module. At this time, the startup signal input terminal PD_HV inputs a shutdown signal to shut down the startup module. Specifically, when the startup module needs to be shut down, the startup signal is pulled high to shut down the fifth PMOS tube PM5, thereby achieving the purpose of shutting down the startup module.

[0030] In some embodiments, the startup current I1 provided by the startup module to the oscillator module is 200nA~5μA. The startup current I1 is preferably 300nA, and may also be 200nA, 500nA, 700nA or 1μA, 2μA, 3μA. The startup current I1 may also be provided by the bias current generated by other modules in the chip system, as long as it is greater than the current of the startup oscillator module.

[0031] In a specific embodiment, Figure 1 As shown, the gate of the first PMOS tube PM1 and the gate of the first NMOS tube NM1 are connected to the start signal input terminal PD_HV; the source of the first PMOS tube PM1 is connected to the power supply, and the drain of the first PMOS tube PM1 is connected to the drain of the first NMOS tube NM1, the gate of the second NMOS tube NM2 and the drain of the sixth NMOS tube NM6; the source of the first NMOS tube NM1 and the sixth NMOS tube NM6 is grounded; the source of the second PMOS tube PM2, the third PMOS tube PM3, the fourth PMOS tube PM4 and the fifth PMOS tube PM5 are connected to the power supply; the gate of the second PMOS tube PM2 is connected to the output end of the second inverter N2, and the drain is connected to the drain of the second NMOS tube NM2; the gates of the third PMOS tube PM3, the fourth PMOS tube PM4 and the fifth PMOS tube PM5 are connected to each other and connected to the first The drain of the second PMOS tube PM2; the drain of the fifth PMOS tube PM5 is connected to the current switching module to output the startup current I1 for the current switching module; the sources of the second NMOS tube NM2, the third NMOS tube NM3 and the fourth NMOS tube NM4 are grounded; the drain and the gate of the third NMOS tube NM3 are connected to each other and to the drain of the third PMOS tube PM3; the gate of the fourth NMOS tube NM4 is connected to the gate of the first NMOS tube NM1 and the startup signal input terminal PD_HV, and the drain is connected to the gates of the third NMOS tube NM3, the fifth NMOS tube NM5 and the sixth NMOS tube NM6; the drain of the fifth NMOS tube NM5 is connected to the drain of the fourth PMOS tube PM4, and the source is connected to one end of the first resistor R1, and the other end of the first resistor R1 is connected to the gate of the first NMOS tube NM1 and the startup signal input terminal PD_HV.

[0032] In a specific embodiment, Figure 1As shown, the oscillator module is a Pierce oscillator, including an NMOS tube Mn, a 32.768K crystal, a second capacitor C2 and a third capacitor C3; one end of the 32.768K crystal is connected to the second capacitor C2 and the first load X1, and the other end is connected to the second load X2 and the third capacitor C3, and the other ends of the second capacitor C2 and the third capacitor C3 are grounded; a second resistor R2 is also connected between the first load X1 and the second load X2; the gate of the NMOS tube Mn is connected to the output module, the source is grounded, and the drain is connected to the switching module. When current flows through the drain of the NMOS tube Mn, the Pierce oscillator resonates with the 32.768K crystal, and an oscillating sine wave is generated at both ends of the 32.768K crystal. When resonating, the crystal behaves as a very small resistor. In some embodiments, the second resistor is a 10Mohm resistor.

[0033] Preferably, if Figure 1 As shown, the output module includes a first capacitor C1, a third inverter N3, a fourth inverter N4 and a fifth inverter N5 connected in sequence, the first capacitor C1 is also connected to the oscillator module; the output end of the third inverter N3 is also connected to its input end; the fifth inverter N5 outputs the amplified oscillation signal to the subsequent circuit.

[0034] Specifically, the output module is used to amplify the amplitude of the oscillation signal output by the oscillator module and increase the driving capability. The output module adopts an operational amplifier structure to output a stable 32.768k clock signal.

[0035] It should be understood that the above are only preferred embodiments of the present invention, and the patent scope of the present invention cannot be limited thereto. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. An ultra-low power consumption driving circuit, comprising a startup module, an oscillator module and an output module, characterized in that: The driving circuit further includes a power supply module and a current switching module; the starting module and the power supply module are connected to the oscillator module through the current switching module, and the oscillator module is connected to the output module; The current switching module is connected to the starting module to provide a starting current to the oscillator module, so that the oscillator module starts to work and outputs an oscillation signal; After the oscillator module starts to work, the current switching module switches on the power supply module to provide the oscillator module with working current, and switches off the start-up module; the output module is used to amplify and output the oscillation signal; The startup module includes a second inverter, a first PMOS tube, a second PMOS tube, a third PMOS tube, a fourth PMOS tube, a fifth PMOS tube, a first NMOS tube, a second NMOS tube, a third NMOS tube, a fourth NMOS tube, a fifth NMOS tube, a sixth NMOS tube and a first resistor; The input ends of the first PMOS tube, the first NMOS tube and the second inverter are connected to the start signal input end; the second PMOS tube is connected to the output end of the second inverter; the third PMOS tube, the fourth PMOS tube and the fifth PMOS tube are connected to the second PMOS tube; the second NMOS tube is connected to the first PMOS tube; the third NMOS tube is connected to the third PMOS tube, the fourth NMOS tube and the fifth NMOS tube; the sixth NMOS tube is connected to the first PMOS tube and the first NMOS tube; The first resistor is connected to the fifth NMOS tube; The gate of the first PMOS tube and the gate of the first NMOS tube are connected to the start signal input terminal; the source of the first PMOS tube is connected to a power supply, and the drain of the first PMOS tube is connected to the drain of the first NMOS tube, the gate of the second NMOS tube and the drain of the sixth NMOS tube; the sources of the first NMOS tube and the sixth NMOS tube are grounded; The sources of the second PMOS tube, the third PMOS tube, the fourth PMOS tube and the fifth PMOS tube are connected to a power supply; the gate of the second PMOS tube is connected to the output end of the second inverter, and the drain is connected to the drain of the second NMOS tube; the gates of the third PMOS tube, the fourth PMOS tube and the fifth PMOS tube are connected to each other and to the drain of the second PMOS tube; the drain of the fifth PMOS tube is connected to the current switching module to output a startup current for the current switching module; The sources of the second NMOS tube, the third NMOS tube and the fourth NMOS tube are grounded; the drain and the gate of the third NMOS tube are connected to each other and to the drain of the third PMOS tube; the gate of the fourth NMOS tube is connected to the gate of the first NMOS tube and the start signal input terminal, and the drain is connected to the gates of the third NMOS tube, the fifth NMOS tube and the sixth NMOS tube; the drain of the fifth NMOS tube is connected to the drain of the fourth PMOS tube, and the source is connected to one end of the first resistor, and the other end of the first resistor is connected to the gate of the first NMOS tube and the start signal input terminal.

2. The ultra-low power consumption driving circuit according to claim 1, characterized in that: The startup module provides a startup current of 200 nA to 5 μA for the oscillator module.

3. The ultra-low power consumption driving circuit according to claim 2, characterized in that: The magnitude of the starting current is 300nA.

4. The ultra-low power consumption driving circuit according to claim 1, characterized in that: The power supply module provides the oscillator module with a working current of 50nA to 80nA.

5. The ultra-low power consumption driving circuit according to claim 4, characterized in that: The magnitude of the operating current is 60nA.

6. The ultra-low power consumption driving circuit according to claim 1, characterized in that: The current switching module includes a first transmission gate connected to the startup module and a second transmission gate connected to the power supply module, the first transmission gate is connected to the switching signal input terminal, and the second transmission gate is connected to the switching signal input terminal through a first inverter; The first transmission gate and the second transmission gate receive switching signals respectively to respectively switch on / off the startup current and the operating current.

7. The ultra-low power consumption driving circuit according to claim 1, characterized in that: The output module includes a first capacitor, a third inverter, a fourth inverter and a fifth inverter connected in sequence, the first capacitor is also connected to the oscillator module; the output end of the third inverter is also connected to its input end; the fifth inverter outputs the amplified oscillation signal to the subsequent circuit.

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