A kind of rram voltage generating system

Abstract

An RRAM voltage generation system comprises a charge pump (12), a square-wave oscillator (13), a linear voltage regulator (14), a power-on control circuit (15), and a voltage and current reference source (11). The charge pump (12) is used for raising a voltage of an external power source and providing a power source to another sub-circuit. The square-wave oscillator (13) is used for providing a clock signal, and an output end of the square-wave oscillator (13) is connected to a clock signal input end of the charge pump (12). The linear voltage regulator (14) is used for providing a driving voltage for the operation of a storage unit, and an output end of the linear voltage regulator (14) is sequentially connected to a row and column decoder (2) and a storage unit array (3). The linear voltage regulator (14) is also connected to an external power source VCC and a charge pump (12) output power source VPP. The power-on control circuit (15) is used for providing a power-on reset signal to a system, and also controlling the sequential start of the charge pump (12), the square-wave oscillator (13) and the linear voltage regulator (14). The voltage and current reference source (11) is used for providing a reference voltage and a reference current to the charge pump (12), the square-wave oscillator (13), the linear voltage regulator (14) and the power-on control circuit (15). Both an external power source and the charge pump (12) of a double-branch structure with good technological compatibility are used to separately supply power to the linear voltage regulator (14), and multiple bytes are supported.

Description

technical field [0001] The invention relates to the field of memory, in particular to an RRAM voltage generation system. Background technique [0002] Resistive random access memory (RRAM) is a new type of non-volatile information storage technology, which has the characteristics of simple structure, compatible with standard CMOS technology, low operating voltage, low power consumption and high-speed reading and writing. Its storage information unit is realized by a variable resistor exhibiting bipolar memory characteristics of a high resistance state (for example: 100Kohm) and a low resistance state (for example: 10Kohm). [0003] In order to convert the variable resistor between the low-resistance state and the high-resistance state, it is necessary to configure the variable resistor under different voltage or current working conditions. [0004] figure 1 Shown is a group of typical 1T1R (1 transistor and 1 variable resistor) memory cell voltage configuration diagrams, w...

AI Technical Summary

Problems solved by technology

[0011] Although the above-mentioned existing scheme can provide all required voltages for RRAM, there are still the following disadvantages: 1) This scheme does not support simultaneous operation of multi-byte Bytes storage units; it is mentioned in the original text that the charge pump adopts a Dickson charge pump, and its load The maximum is 1mA; it can be speculated that this solution is only used to support the simultaneous SET / RESET operation of memory units less than 1 byte (8bits); if it is necessary to support multiple bytes (eg 16Bytes=128bits) memory units simultaneously SET / RESET operation, that is, the load current of the charge pump will be very large (>16mA); 2) Using a 3-stage Dickson charge pump, the voltage loss is large, the load driving ability is low, and the power efficiency is low; to achieve sufficient driving ability and Output voltage, the layout area of ​​this scheme becomes larger, and the cost of the chip increases; 3) The switching of the storage unit or the switching of the SET / RESET mode (that is, the voltage provided to the storage unit drops rapidly) adopts the "leakage path" method: an additional pulse is required The wide signal controls the leakage path, and at the same time, the voltage after switching cannot be quickly and accurately stabilized to the target value (that is, there is a certain deviation between the actual value after switching and the target value), which affects the normal operation of subsequent memory cells; The LDO types of line WL, bit line BL and source line SL are explained in detail, which is not conducive to the realization of high-efficiency solutions

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