Patent Application
20200381995
Dynamic random access memory (DRAM) is widely used because of its available density, speed, and relatively low cost. In the DRAM circuit, the power system is designed with several charge pumps to provide sufficient operation voltage and current to memory arrays. However, the operation current of the memory arrays varies accordingly with a system temperature of the DRAM circuit during operation. An efficient way to manage power consumption in DRAM circuits at different system temperatures is needed in the application.
One aspect of the present disclosure is related to a voltage supply device. In accordance with some embodiments of the present disclosure, the voltage supply device comprises a plurality of pump units and a temperature sense circuit. The plurality of pump units are configured to generate a pump voltage in response to an oscillating signal. The temperature sense circuit is configured to sense a system temperature and to generate, according to the system temperature, sense data for generating a control signal configured to enable a first pump array in the plurality of pump units.
Another aspect of the present disclosure is related to a voltage supply device. In accordance with some embodiments of the present disclosure, the voltage supply device comprises a sense circuit, an oscillator circuit, a pump circuit and a temperature sense circuit. The sense circuit is configured to receive a feedback signal and output a first control signal. The oscillator circuit is coupled to the sense circuit, and configured to receive the first control signal and accordingly output an oscillating signal when the first control signal is enabled. The voltage generating circuit comprises a plurality of first cores and a plurality of second cores. The plurality of first cores are configured to output a voltage in response to the oscillating signal, and the plurality of second cores are configured to be enabled in response to a second control signal to output the voltage. The temperature sense circuit is coupled to the voltage generating circuit, and configured to provide sense data for generating the second control signal according to a system temperature detected by the temperature sense circuit.
Another aspect of the present disclosure is related to a method. In accordance with some embodiments of the present disclosure, the method comprises the following steps: sensing, by a temperature sense circuit, a system temperature, to generate sense data, generating a control signal corresponding to the sense data and controlling, by the control signal, a number of pump units in a pump circuit that is configured to generate a pump voltage, to be enabled.
Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures. It is noted that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.
The following disclosure provides many different embodiments, or examples, for implementing different features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the some embodiments and/or configurations discussed.
The terms used in this specification generally have their ordinary meanings in the art and in the specific context where each term is used. The use of examples in this specification, including examples of any terms discussed herein, is illustrative only, and in no way limits the scope and meaning of the disclosure or of any exemplified term. Likewise, the present disclosure is not limited to some embodiments given in this specification.
Although the terms “first,” “second,” etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of the embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
The terms “comprise,” “comprising,” “include,” “including,” “has,” “having,” etc. used in this specification are open-ended and mean “comprises but not limited.”
Please refer to
The sense circuit 110 is configured to receive a feedback signal FS with a pump voltage Vpump generated from the pump circuit 130 and output a signal S1 with a logic value, for example, logic 0 or logic 1. The oscillator circuit 120 is configured to receive the signal S1 and accordingly output an oscillating signal OS when the signal S1 is enabled and has a logic value 1. The pump circuit 130 includes a plurality of pump units 131a-131n. In some embodiments, the pump circuit 130 can be referred as a voltage generating circuit including a plurality of cores to output a voltage. The plurality of cores can be implemented with the plurality of pump units illustrated in the pump circuit 130. Pump units of the plurality of pump units 131a-131n are coupled with each other in parallel, and configured to generate the pump voltage Vpump in response to the oscillating signal OS. In some embodiments, the plurality of pump units 131a-131n can be separated into a pump array 131a-131d and a pump array 131e-131n (circled with dash line in
Reference is made with
In some other embodiments, each of a plurality of logic gates can be connected each one of pump units. Furthermore, the plurality of logic gates cannot be included in the control circuit 150, but can be included in the pump circuit 130 in order to receive the signal generated by the control circuit 130 to enable or disable the corresponding pump units connected with the plurality of logic gates. In such a way that all the pump units included in the pump circuit 130 are controlled by the control signal CS to be enabled.
As the embodiments aforementioned, for example, the control circuit 150 receives the sense data SD corresponding to a certain system temperature and generates the control signal with 3-bit value such as value 001. That is, the first bit is 1 allocated at the most right. The second bit is 0 allocated in the middle of the value. The third bit is 0 allocated at the lost left. In some embodiments as shown in
For illustration, in some embodiments of the voltage supply device 100, the sense circuit 110 in
In some embodiments, the voltage supply device 100 illustrated above operates as a power system to provide memory arrays in a DRAM circuit an operation voltage and operation current. It is known for a person having ordinary skill in the art that as the system temperature of the DRAM circuit increases, the required operation current of the memory arrays increases. Alternately, the voltage supply device 100 requires providing greater current to the memory arrays. For example, when the required operation current corresponding the system temperature at 85° C. is 50 milliampere (mA), ten pump units are needed to provide sufficient current while each pump unit provides current with 5 mA. As system temperature increases to 100° C. and the required operation current turns to be 55 mA, apart from the original ten pump unit, one spare pump unit configured in the voltage supply device 100 is enabled to provide compensated current for the increase of the system temperature. If the system temperature is continuously increasing during the operation, more spare pump units are enabled to provide sufficient compensated current. In other words, the spare pump units can be enabled or disabled according to the system temperature in order to manage power consumption caused by the spare pump units.
Reference is made to
Next, by performing the step 320, in some embodiments, the control circuit 150 is configured to determine whether the system temperature Ts is above a first temperature T1 (i.e., 85° C., the system temperature of ordinary DRAM circuit operating under normal condition, provided by JTAG template) based on the sense data SD and accordingly output the control signal CS and control, by the control signal CS, a number of pump units 131a-131n in the pump circuit 130 that is configured to generate the pump voltage Vpump, to be enabled. When the system temperature Ts is above the first temperature T1, the step 330 is performed. Otherwise, the step 340 is performed.
In step 340, in some embodiments, when the system temperature is below the first temperature T1, the control circuit 150 is configured to disable the pump array 131e-131n with the control signal CS having value 000 while the pump array 131a-131d is enabled to output the pump voltage Vpump by receiving the oscillating signal OS generated by the oscillator circuit 120. To put in another way, the pump array 131e-131n is electrically disconnected to the oscillator circuit 120.
On the other hand, in step 330, in some embodiments, the pump array 131a-131d is enabled and the control circuit 150 is further configured to enable at least one pump unit of the pump array 131e-131n with the control signal CS having a value 001. As the embodiment shown in
Next, in the step 350, in some embodiments, the control circuit 150 continues to determine whether the system temperature Ts is above a second temperature T2, for example, 100° C. When the system temperature Ts ranges between the first temperature T1 (i.e., 85° C.) and the second temperature T2 (i.e., 100), the step 330 is performed continuously. When the system temperature Ts is above the second temperature T2, the step 360 is performed.
In the step 360, in some embodiments, the pump array 131a-131d remains enabled and the control circuit 150 is further configured to enable more pump unit of the pump array 131e-131n with the control signal CS having a value 011. As the embodiment shown in
In addition, in the step 370, the control circuit 150 continues to determine whether the system temperature Ts is above a third temperature T3, for example, 131° C. When the system temperature Ts ranges is below the third temperature T3, the step 360 is performed continuously. When the system temperature Ts is above the second temperature T3, the step 380 is performed.
In the step 380, in some embodiments, the pump array 131a-131d remains enabled and the control circuit 150 is further configured to enable all pump units of the pump array 131e-131n with the control signal CS having a value 111.
As discussed above, in some embodiments, the pump units in the pump array 131e-131n are controlled by the control signal SC to be separately enabled. For example, as the embodiment shown in
Reference is made as in the
Corresponding to the method 300, in some embodiments, when the system temperature Ts increases, the temperature sense circuit 140 is further configured to generate updated sense data SD for modifying the control signal CS in order to enable an increased number of pump units in the pump array, for example, the pump array 131e-131n is
By the same token, in some embodiments, when the system temperature Ts decreases from 135° C. to 105° C. during the operation, signifying that the memory array (not shown in the figures) needs less current compared to the required current at higher temperature, the temperature sense circuit 140 generates updated sense date SD with the information of the system temperature Ts indicating 105° C. Moreover, the control circuit 150 included in the temperature sense circuit 140, not included in the temperature sense circuit 140 or included in the pump circuit 130 modifies the control signal CS, so that the control CS is updated from having value 111 to value 011. Consequently, as shown in
It should be noted that, as the embodiments aforementioned, the control circuit 150 can be configured to modify the control signal CS regarding different temperature intervals. In some embodiments, the control signal CS can be modified during every 5° C. or non-linear temperature interval, such like 85° C.-95° C., 96° C.-111° C. and 112° C.-132° C. Specifically, for example, the temperature interval can be 81° C.-85° C., 86° C.-90° C., 91° C.-95° C., 96° C.-100° C. and 101° C.-105° C., etc. In this way, when the system temperature Ts increases from 81° C. to 100° C., the control signal CS can be modified for four times, accordingly, and the number of pump units being enabled in the pump array 131e-131n varies four times, for example, from zero pump unit enabled to three pump units enabled. In other embodiments, the control circuit 150 can be configured to generate the control signal CS based on the sense signal SD and a threshold temperature. When the system temperature Ts is below or equal to the threshold temperature, no spare pump units, for example pump units 131e-131n, are enabled. When the system temperature Ts is above the threshold temperature, all the spare pump units are enabled. The number of pump units in the pump array 131e-131n, the temperature intervals are given for an exemplary purpose of ease of understanding the present disclosed, but the present disclosure is not limited therein.
Furthermore, the pump units in the present disclosure can be identical to each other, providing same current value, or different to each other. Various ways to implement the function of the pump units in the pump circuit are within the contemplated scope of the present disclosure.
In summary, in various embodiments of the present disclosure, by enabling or disabling the a plurality of pump unit configured to provide the voltage according the a control signal corresponding to the system temperature of the DRAM circuit, the power consumption of the DRAM circuit during operation at high and low temperature can be managed preciously without complicated configuration of circuits.
It is noted that, the drawings, the embodiments, and the features and circuits in the various embodiments may be combined with each other as long as no contradiction appears. The circuits illustrated in the drawings are merely examples and simplified for the simplicity and the ease of understanding, but not meant to limit the present disclosure.
The foregoing outlines features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure.
