U.S. patent application number 12/877572 was filed with the patent office on 2010-12-30 for electronic system capable of compensating process, voltage and temperature effects.
This patent application is currently assigned to Media Tek Inc.. Invention is credited to Yu-Ping Ho, Chih-Hung Shen, Mao-Lin Wu.
Application Number | 20100327952 12/877572 |
Document ID | / |
Family ID | 39313233 |
Filed Date | 2010-12-30 |
United States Patent
Application |
20100327952 |
Kind Code |
A1 |
Wu; Mao-Lin ; et
al. |
December 30, 2010 |
Electronic System Capable of Compensating Process, Voltage and
Temperature Effects
Abstract
An electronic system includes an integrated circuit, powered by
a first voltage, with a first device provided therein; a detection
device coupled to the first device to detect an output deviation of
the first device attributed to process, voltage and temperature
(PVT) effects; and a compensation device coupled to the detection
device, adjusting the first voltage in response to the output
deviation and outputting the first voltage to the integrated
circuit to compensate for the PVT effects. The electronic system
further comprises a conversion device, coupled between the
detection device and the compensation device, to generate an
indication signal corresponding to the output deviation for the
compensation device to adjust the first voltage. In addition, the
compensation device may compare and amplify a difference between a
voltage level of the indication signal and a reference to linearly
adjust the first voltage for compensating for the PVT effects.
Inventors: |
Wu; Mao-Lin; (Jhubei City,
TW) ; Shen; Chih-Hung; (Chung-Ho City, TW) ;
Ho; Yu-Ping; (Feng-Shan City, TW) |
Correspondence
Address: |
THOMAS, KAYDEN, HORSTEMEYER & RISLEY, LLP
600 GALLERIA PARKWAY, S.E., STE 1500
ATLANTA
GA
30339-5994
US
|
Assignee: |
Media Tek Inc.
Hsin-Chu
TW
|
Family ID: |
39313233 |
Appl. No.: |
12/877572 |
Filed: |
September 8, 2010 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
11859844 |
Sep 24, 2007 |
7812661 |
|
|
12877572 |
|
|
|
|
Current U.S.
Class: |
327/513 |
Current CPC
Class: |
H03K 19/00369
20130101 |
Class at
Publication: |
327/513 |
International
Class: |
H01L 37/00 20060101
H01L037/00 |
Claims
1. An electronic system comprising: a voltage regulator coupled to
a main source to output a second source, comprising a thermal
sensor to monitor temperature of the electronic system, the voltage
regulator adjusting voltage level of the second source according to
a sensing result of the thermal sensor; and an integrated circuit
powered by the second source.
2. The electronic system as claimed in claim 1, wherein the thermal
sensor is a thermister with resistance changed in response the
temperature.
3. The electronic system as claimed in claim 1, wherein the
electronic system adjusts the second source linearly.
4. An electronic system comprising: an integrated circuit powered
by a first voltage, comprising a first device generating a desired
output; a detection device coupled to the first device to detect an
output deviation of the first device, from the desired output, and
the deviation output attributed to process, voltage and temperature
(PVT) effects; a compensation device coupled to the detection
device, adjusting the first voltage in response to the output
deviation and outputting the first voltage to the integrated
circuit to compensate the PVT effects; a main source powering the
electronic system; and a voltage regulator coupled to the main
source outputting a second source to the integrated circuit;
wherein the voltage regulator comprises a thermal sensor to monitor
temperature of the electronic system, and the voltage regulator
adjusts voltage level of the second source according to a sensing
result of the thermal sensor.
5. The electronic system as claimed in claim 4, wherein the thermal
sensor is a thermister with resistance changed in response the
temperature.
6. The electronic system as claimed in claim 4, wherein the
electronic system adjusts the second source linearly.
7. An electronic system comprising: an integrated circuit powered
by a second source; and a voltage regulator coupled to a main
source outputting the second source, comprising: a transistor
coupled between the main source and a reference voltage; and a
thermal sensor, coupled between a control terminal of the
transistor and the reference voltage; wherein the thermal sensor
monitors temperature of the electronic system, and the voltage
level of the second source is adjusted according to a sensing
result of the thermal sensor.
8. The electronic system as claimed in claim 7, wherein the thermal
sensor is a thermister with resistance changed in response the
temperature.
9. The electronic system as claimed in claim 8, wherein emitter
current of the transistor is changed in response to resistance
change of the thermal sensor.
10. The electronic system as claimed in claim 7, wherein the
transistor is operated in a linear amplification zone.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. patent
application Ser. No. 11/859,844, filed Sep. 24, 2007, the entirety
of which is incorporated herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an electronic system, and
in particular relates to an electronic system capable of
compensating for process, voltage and temperature (PVT) effects
with simple and low cost circuitry design.
[0004] 2. Description of the Related Art
[0005] Output signals of electronic systems such as integrated
circuits, lump circuits or combination thereof are distorted in
response to temperature variations, such that electrical
characteristics (voltage, current and so on) and timings such as
setup/hold times may deviate or drift from the expected values of
original designs, resulting in system malfunction. Generally,
engineers perform chamber burn-out tests to electronic products to
identify whether designed firmware parameters conform with
operational requirements at high/low temperature surroundings.
Designing electronic products based on tested firmware parameters,
does not necessary guarantee operational stability, especially when
operating in different surroundings or with other peripheral
conditions. If iterative modified tests are required, test time and
fabrication costs would increase. In addition to the above
mentioned temperature fluctuation effect, electronic products,
especially integrated circuits, may also suffer from
process/voltage deviation effects, for example, when fabricated by
different processes.
BRIEF SUMMARY OF INVENTION
[0006] The invention is directed to an electronic system capable of
compensating for process, voltage and temperature (PVT) effects
with simple and low cost circuitry design.
[0007] An embodiment of the invention proposes an electronic system
comprising: an integrated circuit which is powered by a first
voltage and has a first device provided therein; a detection device
coupled to the first device to detect an output deviation of the
first device attributed to process, voltage and temperature (PVT)
effects; and a compensation device coupled to the detection device,
adjusting the first voltage in response to the output deviation and
outputting the first voltage to the integrated circuit to
compensate for the PVT effects. Also, the electronic system further
comprises a conversion device, coupled between the detection device
and the compensation device. The conversion device generates an
indication signal corresponding to the output deviation detected by
the detection device for the compensation device to adjust the
first voltage. In addition, the compensation device may compare and
amplify a difference between a voltage level of the indication
signal and a reference to linearly adjust the first voltage for
compensating for the PVT effects.
[0008] Another embodiment of the invention proposes an electronic
system comprising: a thermal sensor to monitor temperature of the
electronic system or the integrated circuit; a voltage regulator
adjusting voltage level of the second source according to a sensing
result of the thermal sensor; and an integrated circuit powered by
a the second source. The thermal sensor is a thermister with
resistance changed in response temperature.
[0009] A detailed description is given in the following embodiments
with references to the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0010] The present invention can be more fully understood by
reading the subsequent detailed description and examples with
references made to the accompanying drawings, wherein:
[0011] FIG. 1A schematically shows circuit block diagrams of an
electronic system 100 according to an exemplary embodiment of the
invention.
[0012] FIG. 1B schematically shows circuit block diagrams of an
electronic system 150 according to another exemplary embodiment of
the invention.
[0013] FIG. 2 schematically shows circuit block diagrams of an
electronic system 200 according to yet another exemplary embodiment
of the invention.
[0014] FIG. 3 schematically shows circuit block diagrams of an
electronic system 300 according to yet another further exemplary
embodiment of the invention.
DETAILED DESCRIPTION OF INVENTION
[0015] The following description is of the best-contemplated mode
of carrying out the invention. This description is made for the
purpose of illustrating the general principles of the invention and
should not be taken in a limiting sense. The scope of the invention
is best determined by reference to the appended claims.
[0016] FIG. 1A schematically shows circuit block diagrams of an
electronic system 100 according to an exemplary embodiment of the
invention. In FIG. 1A, the electronic system 100 comprises an
integrated circuit 101, a first device 101a, a detection device
101b, a conversion device 101c and a compensation device 102. The
integrated circuit 101 receives a first voltage V.sub.1 at its
power terminal T.sub.p. The integrated circuit 101 may have a power
module (not shown in FIG. 1A) provided therein to perform power
management and device driving.
[0017] The first device 101a provided inside the integrated circuit
101, for example, is a ring oscillator which is designed to output
a predetermined frequency and voltage. The output frequency (or
voltage) of the ring oscillator (first device) 110a may be
distorted due to process, voltage and temperature (PVT) effects,
thus resulting in output deviation from the predetermined frequency
(or voltage) for the ring oscillator 101a. Please note that the PVT
effects in this invention are defined to reflect the influence of
one or more of process, voltage, and temperature deviation. The
detection device 101b, provided inside the integrated circuit, is
coupled to the first device 101a to detect the output deviation of
the first device 110a attributed to the PVT effects. In this
embodiment, the detection device 101b may comprise a frequency
counter, for example, but is not limited thereto, to determine
frequency deviation from the predetermined frequency to the actual
frequency output of the ring oscillator 101a. Here, the detection
device 101b may output digital data of a deviation counting number
in response to the frequency deviation, for example.
[0018] The conversion device 101c receives the digital data from
the detection device 101b and converts the digital data to an
indication signal corresponding to the frequency deviation. Here,
the conversion device 101c may be a digital-to-analog converter
(DAC), converting the digital data to a direct current (DC) voltage
V.sub.DC. Next, the compensation device 102 receives the DC voltage
V.sub.DC and adjusts the first voltage V.sub.1 in response to the
frequency deviation of the ring oscillator 101a and outputs the
adjusted first voltage V.sub.1 to the integrated circuit 101 to
compensate the PVT effects.
[0019] The compensation device 102 may compare and amplify a
weighted difference (i.e.,
.alpha..times.V.sub.DC-.beta..times.V.sub.REF) between the DC
voltage V.sub.DC of the indication signal and a reference voltage
V.sub.REF to linearly adjust the first voltage V.sub.1. For
example, the compensation device 102 may comprise an operational
amplifier 102a, resisters R1, R2 and R3 as depicted in FIG. 1A, but
is not limited thereto. The first voltage V.sub.1 is determined
according to the DC voltage V.sub.DC, the reference voltage
V.sub.REF and the amplification ratio is dependant upon R1 and R2,
respectively. The operational amplifier 102a is used to ensure that
sufficient driving voltage (i.e., V.sub.1) and driving current can
be provided to the integrated circuit 101.
[0020] In FIG. 1A, the first device 101a, the detection device 101b
and the conversion device 101c are provided inside of the
integrated circuit 101. Alternatively, the conversion device (DAC)
can be provided outside of the integrated circuit 101. FIG. 1B
schematically shows circuit block diagrams of an electronic system
150 according to another exemplary embodiment of the invention. The
electronic system 150 comprises an external conversion device (DAC)
152 provided outside of the integrated circuit 101. The electronic
system 150 has the same functions and operations as that of the
electronic system 100 described above. In FIG. 1B, the detection
device 101b may communicate with the external ADC 152 through
parallel interface, serial interface or I.sup.2C interface.
[0021] FIG. 2 schematically shows circuit block diagrams of an
electronic system 200 according to yet another exemplary embodiment
of the invention. In FIG. 2, the electronic system 200 comprises an
integrated circuit 201, a first device 201a, a detection device
201b, a conversion device 201c, a low-pass filter 203 and a
compensation device 202. The integrated circuit 201 receives a
first voltage V1 at its power terminal Tp. The integrated circuit
201 may have a power module (not shown in FIG. 2) provided therein
to perform power management and drive devices. In FIG. 2, the first
device 201a and the detection device 201b have the same functions
and features as that of the first device 101a and detection device
101b of FIG. 1A, therefore further description will not be provided
for brevity.
[0022] The first device 201a provided inside the integrated circuit
201, for example, is a ring oscillator which is designed to output
a predetermined frequency and voltage. The detection device 201b,
provided inside the integrated circuit 201, is coupled to the first
device 201a to detect an output deviation of the first device 201a
attributed to the PVT effects. Also, the detection device 201b
determines frequency deviation from the predetermined frequency to
the actual frequency output of the ring oscillator 201a.
[0023] The conversion device 201c receives and converts the
frequency deviation determined by the detection device 201b to an
indication signal. Here, for example, the conversion device 201c is
a pulse width modulation device (PWM), outputting PWM signal
S.sub.PWM as the indication signal according to the frequency
deviation. The PWM signal S.sub.PWM has a PWM frequency PWM_f and a
PWM duty PWM_d defined as follows: PWM_f=CLK_ref/256.times.pwmp,
and PWM_d=Cal_Cnt/256, where CLK_ref is a frequency of a reference
clock, pwmp and Cal_Cnt are control variables (both within the
range of 1.about.256, controlled through a software, for example),
and the numeral 256 means 8-bit resolution or control scale. In
this embodiment, the PWM device 201c adjusts the variable pwmp or
Cal_Cnt to specify the output frequency or duty of the PWM signal
respectively so as to response to the frequency deviation.
Therefore, the conversion device 201c can output PWM signal
S.sub.PWM with 256 different duty cycles (or different frequency)
to identify the frequency deviation.
[0024] The low-pass filter 203 is a RC network made of resistors
and capacitors. The low-pass filter 203 filters the PWM signal
S.sub.PWM via RC charging/discharging to obtain a direct current
(DC) voltage V.sub.DC. The level of the DC voltage V.sub.DC is in
proportion to the duty of the PWM signal S.sub.PWM.
[0025] The compensation device 202 has the same function and
structure as that of the compensation device 102, thus further
description will not be provided for brevity. The compensation
device 202 may compare and amplify a weighted difference between
(or in relation with) the DC voltage V.sub.DC of the indication
signal and a reference voltage V.sub.REF to linearly adjust the
first voltage V.sub.1. The first voltage V.sub.1 is determined
according to the reference voltage V.sub.REF and the amplification
ratio R1/R2. The operational amplifier 201a ensures sufficient
driving voltage (i.e., V.sub.1) and driving current is provided to
the integrated circuit 201. The DC voltage V.sub.DC comprises 256
different levels corresponding to 256 different frequency
deviations. Therefore, the compensation device 202 can linearly
adjust the first voltage using 256 scales, improving compensating
accuracy and adjustable range.
[0026] FIG. 3 schematically shows circuit block diagrams of an
electronic system 300 according to yet another further exemplary
embodiment of the invention. The electronic system 300 comprises a
voltage regulator 302 and an integrated circuit 301. The voltage
regulator 302 is coupled to a main power source V.sub.DD to output
a second source Vo to the integrated circuit, and comprises a
thermal sensor 302a to monitor temperature of the electronic system
300 or the integrated circuit 301. The voltage regulator 302
adjusts voltage level of the second source Vo according to the
sensing result of the thermal sensor 302a to compensate for
temperature effect. In this embodiment, the voltage regulator 302
comprises an NPN bipolar junction transistor BJT (or other type of
transistor), resistors Ra.about.Rc and a thermister R.sub.T serving
as the thermal sensor 302a. When temperature changes, the
resistance of the thermister R.sub.T changes in response to
temperature changes. Emitter current I.sub.E of the transistor BJT
is changed in response to resistance change of the thermister
R.sub.T. The second source Vo equals I.sub.E.times.Re, where
resistance Re means equivalent resistance of the internal impedance
of the BJT emitter, resister Rc, and load of the integrated circuit
301. Consequently, the second source Vo changes in response to the
temperature change detected by the thermal sensor 302a, thereby
compensating for the temperature effect. The transistor BJT may be
operated in a linear amplification zone, whereby the electronic
system is capable of adjusting the second source Vo linearly,
having flexible control and being appropriate for practical
requirements.
[0027] The voltage regulator 302 can be provided to the electronic
system 100, 150 or 200 described above. For example, the voltage
regulator 302 can output the second source Vo to the power terminal
T of the integrated circuit, to provide compensation for ambient
temperature of the electronic system or the integrated circuit.
[0028] In view of above descriptions in FIGS. 1A, 1B and 2, the
embodiments of the invention may provide one or more of the
following advantages: (1) being capable of outputting control
signals to compensate for detected PVT effects, (2) linearly
indicating the output deviation and compensate for the PVT effects,
(3) being controlled by software and improving compensating
accuracy, and (4) only requiring a simple circuitry design (using
RC charging/discharging structure or DAC) with low cost. In view of
above descriptions in FIG. 3, the embodiment of the invention has
the following advantages of: (1) automatically detecting
temperature by a thermal sensor, (2) linearly indicating the output
deviation and compensating for the PVT effects, and (3) only
requiring a simple hardware solution.
[0029] While the invention has been described by way of example and
in terms of the preferred embodiments, it is to be understood that
the invention is not limited to the disclosed embodiments. To the
contrary, it is intended to cover various modifications and similar
arrangements (as would be apparent to those skilled in the art).
Therefore, the scope of the appended claims should be accorded the
broadest interpretation so as to encompass all such modifications
and similar arrangements.
* * * * *