KR20010010738A - Power Up Circuit of Memory Device - Google Patents

Abstract

PURPOSE: A circuit for performing a power-up operation for a memory device is provided to reduce a delay time for acquiring power-on state. CONSTITUTION: The device includes a band-gap reference voltage generator(10), a normal reference voltage generator(20), a burn-in reference voltage generator(30), a level selector(40) and an internal voltage generator(50). The band-gap reference voltage generator(10) generates a band-gap reference voltage(VBDREF) to the normal reference voltage generator(20). According to the reference bias signal(VBIAS) for a P-MOS(Metal Oxide Semiconductor) transistor from the normal reference voltage generator(20), the burn-in reference voltage generator(30) generates a reference voltage(VREFB) and a reference bias level signal(VLNG) for a burn-in process. The level selector(40) generates an internal reference voltage(VLR) according to outputs from the normal reference voltage generator(20) and burn-in reference voltage generator(30). According to the internal reference voltage(VLR), the internal voltage generator(50) generates an internal voltage(VPERI). Here, in the level selector(40), an N-MOS transistor(N8) is connected between a common node of sources of 2 N-MOS transistors(N5,N7) and a ground terminal.

Description

Power Up Circuit of Memory Device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power up circuit of a memory device, and more particularly, to a power up circuit of a memory device designed to prevent an internal power generation delay upon initial power on.

Hereinafter, a power up circuit of a conventional memory device will be described with reference to the accompanying drawings.

1 is a configuration diagram illustrating a power up circuit of a conventional memory device, and FIG. 2 is a simulation waveform diagram of a power up circuit of a conventional memory device.

As shown in FIG. 1, the bandgap reference voltage generation circuit unit 1 generating a bandgap reference voltage VBDREF and the bandgap reference voltage as inputs, and receive a reference voltage during normal operation of an internal voltage. The VREFO and the normal reference voltage generation circuit portion 2 of the internal voltage generating the reference bias signal VBIAS of the PMOS transistor and the reference bias signal of the PMOS transistor of the normal reference voltage generation circuit portion 2 as inputs. Burn-in reference voltage generation circuit section 3 for generating a power supply burn-in reference voltage VREFBI and reference bias level signal VLNG, and the normal reference voltage generation circuit section 2 and burn-in. A normal and burn-in level selector circuit section 4 which receives each output signal of the in-reference voltage generating circuit section 3 as an input and generates an internal power supply reference voltage VLR, and the normal and burn-in level select Internal power reference voltage of the circuit section 4 (VL The internal voltage generator 5 receives R) and generates an internal voltage VPERI of the peripheral circuit and the array circuit.

Meanwhile, the normal and burn-in level select circuits configured as described above are configured as a comparison circuit using a differential amplifier.

That is, the first PMOS transistor P1 is applied with the internal reference voltage VREFBI applied to the source, the burn-in entry signal VLBINENB is applied to the gate, and the drain is an output terminal. A drain is connected to the drain of the first PMOS transistor P1, a source is connected to the ground voltage VSSI, and a first NMOS transistor N1 to which a burn-in entry signal is applied to the gate, a power supply voltage VDDI, and ground The second PMOS transistor P2 and the second, third, and fourth NMOS transistors N2, N3, and N4 connected in series between the voltage VSSI, and the power supply voltage VDDI and the ground voltage VSSI. The third PMOS transistor P3 and the fifth and sixth NMOS transistors N5 and N6 connected in series with the gate and the gate and the drain of the sixth NMOS transistor N6 are connected in common, and the gate and ground voltage VSSI It consists of a MOS capacitor (C) connected between.

The source is connected in common to the sources of the second NMOS transistor N2 and the fifth NMOS transistor N5, the drain is connected to the drain of the second NMOS transistor N2, and the gate has a reference voltage for an internal power supply normal. The seventh NMOS transistor N7 is applied.

Here, the gate of the second NMOS transistor N2 is connected to the drain of the first PMOS transistor P1, and an active enable signal LD is applied to the gate of the third NMOS transistor N3. The reference bias level signal VLNG of the NMOS transistor is commonly applied to the gates of the fourth NMOS transistor N4 and the sixth NMOS transistor N6, and the third, sixth, and seventh NMOS transistors N3, N6, and N7 are applied to the gates of the NMOS transistor N4 and the sixth NMOS transistor N6. ) Are commonly connected.

The gates of the second PMOS transistor P2 and the third PMOS transistor P3 are connected in common, and the gate and the drain of the second PMOS transistor P2 are connected in common.

The power-up circuit of the conventional memory device configured as described above, as shown in the simulation waveform of FIG. 2, is formed from the bandgap reference voltage generation circuit unit 1 as the external power supply voltage VDD increases during power-up. The bandgap reference voltage VBDREF is generated, and then an internal voltage VPERI and a VREFO / VREFBI, which is a normal / burn-in reference voltage, are generated.

At this time, the burn-in entry signal VLBINENB becomes "high" (= normal mode), and the VLR level is changed to the VREFO level by comparing the VREFO and VLR levels in the normal and burn-in level select circuit section 4. Let's match.

Next, the active signal LD is a signal for driving to move quickly with the PUPB1 pulse width to increase the response characteristics and to quickly generate the VLR level.

The PUPB1 signal becomes high at about 0.6V (Vt) when the VPERI level starts to be generated by the VPERI level monitor signal and becomes low at about 1.8V when the level is completed.

On the other hand, the VLNG signal is driven at a low voltage for current reduction to the Vt level of the NMOS transistor.

The active enable signal LD is equal to the internal voltage level monitor signal PUPB1 at power up.

However, the following problems exist in the power-up circuit of the conventional memory device as described above.

That is, during power-up, the internal voltage delay occurs due to the delay of the internal power reference voltage level during the internal voltage level monitor signal, and the internal voltage level monitor signal resets the peripheral circuit part. It may cause malfunction if it is not generated enough.

The present invention has been made to solve the conventional problems as described above, the internal power supply at the time of power-on by receiving a signal to monitor the internal power level (Power) at the first power-on to speed up the generation of the internal power supply It is an object of the present invention to provide a power-up circuit of a memory device to speed up the generation delay.

1 is a block diagram showing a power-up circuit of a conventional memory device

2 is a simulation waveform diagram of a power-up circuit of a conventional memory device

3 is a block diagram showing a power-up circuit of the memory device according to the present invention

4 is a simulation waveform diagram of a power-up circuit of a memory device according to the present invention;

Explanation of symbols for the main parts of the drawings

10: band gap reference voltage generation circuit section 20: normal reference voltage generation circuit section

30: burn-in reference voltage generating circuit section 40: normal and burn-in level select circuit section

50: internal voltage generator

The power-up circuit of the memory device according to the present invention for achieving the above object is a bandgap reference voltage generation circuit portion and the normal reference voltage generation circuit portion of the internal voltage, burn-in reference voltage generation circuit portion, normal and burn-in level select In the power-up circuit composed of a circuit portion and an internal voltage generator, the normal and burn-in level select circuits are compared with a comparison circuit using a differential amplifier and an internal power supply normal for improving the response characteristics during power-up to speed up the generation of an internal voltage. And a third NMOS transistor configured between the common source and ground voltages of the first and second NMOS transistors having the gate reference voltage and the internal power source reference voltage as their gate inputs, respectively.

Hereinafter, a power up circuit of a memory device according to the present invention will be described in detail with reference to the accompanying drawings.

3 is a block diagram of a power up circuit of the memory device according to the present invention, and FIG. 4 is a simulation waveform diagram of the power up circuit of the memory device according to the present invention.

As shown in FIG. 3, the bandgap reference voltage generator circuit 10 generating the bandgap reference voltage VBDREF and the bandgap reference voltage are inputted to the reference voltage VREFO during normal operation of the internal voltage. Internal power supply burn-in receiving the normal reference voltage generation circuit unit 20 of the internal voltage generating the reference bias signal VBIAS of the PMOS transistor and the reference bias signal of the PMOS transistor of the normal reference voltage generation circuit unit 20 as inputs Burn-in reference voltage generation circuit section 30 for generating a burn-in reference voltage VREFBI and reference bias level signal VLNG, and burn-in reference voltage generation with the normal reference voltage generation circuit section 20. A normal and burn-in level select circuit unit 40 which receives each output signal of the circuit unit 30 as an input and generates an internal power supply reference voltage VLR, and the normal and burn-in level select circuit unit 40. Internal power supply voltage (VLR) Accept consists of an internal voltage generating unit 50 for generating an internal voltage (VPERI).

Meanwhile, the normal and burn-in level select circuits configured as described above have a comparison circuit using a differential amplifier and an internal power reference normal voltage and an internal power reference voltage which are compared to improve response characteristics at power-up to speed generation of internal voltage. A separate NMOS transistor N8 is configured between the common source and ground voltage of the NMOS transistors N5 and N7 each having a gate input, which will be described in detail below.

That is, the first PMOS transistor P1 is applied to the source, the internal reference voltage VREFBI is applied to the source, the burn-in entry signal VLBINENB is applied to the gate, and the drain is an output terminal, and the first PMOS transistor P1 is applied. Drain is connected to the ground of the first NMOS transistor N1 to which the drain is connected to the ground voltage VSSI and the burn-in entry signal is applied to the gate, and between the power supply voltage VDDI and the ground voltage VSSI. A second PMOS transistor P2 and a second, third, and fourth NMOS transistors N2, N3, and N4 connected in series, and a second voltage connected in series between the power supply voltage VDDI and the ground voltage VSSI. A source is commonly connected to a source of the third PMOS transistor P3 and the fifth and sixth NMOS transistors N5 and N6, and the second and fifth NMOS transistors N2 and N5. 2 is connected to the drain of the NMOS transistor (N2), the gate is an internal power supply A seventh NMOS transistor N7 to which a quasi voltage is applied, a gate and a drain of the sixth NMOS transistor N6 are commonly connected, and a MOS capacitor C connected between a gate and a ground voltage VSSI; An eighth NMOS transistor N8 having a drain connected to the common source of the fifth NMOS transistor N5 and the seventh NMOS transistor N7, a source connected to a ground voltage, and an internal voltage level monitor signal PUPB1 applied to a gate thereof. It is configured to include.

Here, the gate of the second NMOS transistor N2 is connected to the drain of the first PMOS transistor P1, and an active enable signal LD is applied to the gate of the third NMOS transistor N3. The reference bias level signal VLNG of the NMOS transistor is applied to the gate of the 4 NMOS transistor N4.

On the other hand, the eighth NMOS transistor N8 has fifth and seventh NMOSs having two reference voltages VREFO and VLR, respectively, which are compared to improve the response characteristics at the time of power-up to speed up the generation of internal voltages. The transistor is positioned between the common source of the transistors N5 and N7 and the ground voltage VSSI.

In the power-up circuit of the memory device according to the present invention configured as described above, the band gap voltage VBDREF is generated, the internal voltage normal reference voltage VREFO is generated, and the VLNG level is generated as the external power supply VDD rises at power-up. As the VLR level is created, the VPERI level is generated. At this time, PUPB1 becomes High, which pulls node A to the ground voltage VSSI through the eighth NMOS transistor N8 to further improve the response characteristic to generate the VLR level faster. And quickly generate the internal voltage VPERI level.

As described above, the power-up circuit of the memory device according to the present invention has the following effects.

In other words, the PUPB1 signal is received during the internal voltage generation at a high power-up (50 kW), thereby improving the response characteristics through the NMOS transistor, thereby speeding up the generation of the internal voltage.

Claims (2)

A power-up circuit comprising a bandgap reference voltage generation circuit portion, a normal reference voltage generation circuit portion of an internal voltage, a burn-in reference voltage generation circuit portion, a normal and burn-in level select circuit portion, and an internal voltage generation portion, The normal and burn-in level select circuits may include a comparison circuit using a differential amplifier and an internal power supply reference voltage and an internal power supply reference voltage, which are compared to improve the response characteristics at the time of power-up to speed up the generation of the internal voltage, respectively. And a third NMOS transistor configured between the common source and ground voltage of the first and second NMOS transistors. The power up circuit of claim 1, wherein the gate input of the third NMOS transistor receives a signal that is enabled while an internal voltage is generated.