3 research outputs found
์ ์์ฐจ-์๊ฐ ๋ณํ๊ธฐ๋ฅผ ์ด์ฉํ Dynamic Low Dropout Voltage Regulator
ํ์๋
ผ๋ฌธ (์์ฌ)-- ์์ธ๋ํ๊ต ๋ํ์ : ์ตํฉ๊ณผํ๊ธฐ์ ๋ํ์ ์ตํฉ๊ณผํ๋ถ, 2019. 2. ์ ๋์.์ต๊ทผ IoT์ mobile ํ๊ฒฝ์์ ๋์ํ๋ ์์คํ
์ด ์ฆ๊ฐํจ์ ๋ฐ๋ผ SoC์ ๋ด๋ถ์ ์ ์๊ด๋ฆฌ ํ๋ก์ ์ค๊ณ๊ฐ ์ค์์๋๊ณ ์๋ค. ์ต์ SoC๋ ์ ์ ํจ์จ์ ๋์ด๊ธฐ ์ํด SoC ๋ด๋ถ์ ๊ฐ block๋ง๋ค ๊ฐ๊ฐ์ ์ ์ ๊ด๋ฆฌ์ฉ ํ๋ก๋ฅผ ์ถ๊ฐํ์ฌ block์ load์ ๋ง๊ฒ ์ ์ ํ ๊ณต๊ธ ์ ์์ ์ ๊ณตํ๋ค. Low Dropout Voltage Regulator (LDO)๋ ๋น ๋ฅธ ์๋ต์๊ฐ๊ณผ ์ ์ die area๋ก SoC๋ด๋ถ์ ์ ์ฉํ๊ธฐ ์ ํฉํ์ฌ SoC๋ด๋ถ์ ์ ์ ๊ด๋ฆฌ ํ๋ก๋ก ๋๋ฆฌ ์ฌ์ฉ๋๊ณ ์๋ค. ํ์ง๋ง ์ ํ์ ์ํํ๋ฅผ ์ํด Printed Circuit Board (PCB) ๋ฉด์ ์ ์ค์ผ ํ์์ฑ์ด ์์ด ๊ธฐ์กด์ ํฐ ์ธ๋ถ ์ถ๋ ฅ capacitor๋ฅผ ์์ ๋ output capacitor-less LDO์ ๋ํ ๊ด์ฌ์ด ๋์์ก๋ค. ๋ํ mobile ํ๊ฒฝ์์ ๋ฐฐํฐ๋ฆฌ ์๋ช
์ ์ํด ๋ฌธํฑ ์ ์ ๊ทผ์ฒ์์ ๋์์ ํ๋ ์์คํ
์ด ๋ง์์ ธ ๋ฌธํฑ ์ ์ ๊ทผ์ฒ์์ ๊ฐ๋ฅํ Digital LDO (DLDO)์ ๋ํ ์ฐ๊ตฌ๊ฐ ๋ง์ด ์งํ๋์๋ค.
๋ณธ ๋
ผ๋ฌธ์์๋ ๋ฌธํฑ ์ ์ ๊ทผ์ฒ์์ ์๋ํ๋ฉฐ ์ธ๋ถ capacitor์ pad๋ฅผ ์์จ ์ ์๋ output capacitor-less ๋์์ ์ง์ํ๋ dynamic ๊ตฌ์กฐ์ LDO๋ฅผ ์ ์ํ๋ค. ๋ฌธํฑ ์ ์ ๊ทผ์ฒ์์ ์๋์ด ๊ฐ๋ฅํ DLDO์๋ ๋ค๋ฅด๊ฒ ์ ์๋ LDO๋ analog LDO์ ๊ฐ์ด ํ๋์ power transistor๋ฅผ ์ฌ์ฉํ๋ฉฐ, op-amp ๋์ Voltage Difference to Time Converter(VDTC)๋ฅผ ์ ์ํด ๋ฌธํฑ ์ ์ ๊ทผ์ฒ์์์ ๋์์ ๊ฐ๋ฅํ๊ฒ ํ์๋ค. ์ ์๋ VDTC๋ฅผ ํตํดDLDO์์๋ ํ๋ ์ถ๋ ฅ ์ ์์ ripple-lessํน์ฑ์ ๊ฐ์ง ์ ์๋ค. ๋ํ ์์ capacitor๋ก ๋์ ์ฃผํ์์์์ ์ถ๋ ฅ ์ํผ๋์ค ๊ฐ์ ๋ฃจํ๋ฅผ ์ ์ฉํด load transient๊ฐ ๋ฐ์ํ์์ ๋ ์ถ๋ ฅ capacitor ์์ด ์ ์ ์ถ๋ ฅ ์ ์ ๋ณํ๋ฅผ ์ป์๋ค.
์ค๊ณ๋ ํ๋ก๋65nm LP ๊ณต์ ์ผ๋ก ์ ์๋์์ผ๋ฉฐ, ์ ์ฒด ๋ฉด์ ์ 0.0834mm2 ์ด๋ค. ์ ์๋ ๋
ผ๋ฌธ์ ๋์ ๋์ ๋ฒ์๋ฅผ ๊ฐ์ง๋ฉฐ 0.6V ์
๋ ฅ ์ ์์์ ์ต๋ 30mA์ ์ถ๋ ฅ ์ ๋ฅ๋ฅผ ์ ๊ณตํ๋ค. ๋๊ธฐ ์ ๋ฅ๋ 1MHz์ ํด๋ญ์์ 0.1ฮผA์ ์ฌ์ฉํ๋ฉฐ ์ด์ ์ต์ ๋
ผ๋ฌธ๋ณด๋ค 14๋ฐฐ ํฅ์๋ FOM์ ์ป์๋ค.Recently, the design of the on-chip power management circuit of the System-on-Chip (SoC) becomes important as the system which operates in IoT and mobile environment emerges. To maximize power efficiency, modern SoCs need power management block in each block of the SoC to provide the proper supply voltage. Low Dropout Voltage Regulator (LDO) is widely used as power management circuits in SoCs because it suitable to be integrated in SoC with fast response time and low die area. However, there is a need to reduce the printed circuit board (PCB) area in order to miniaturize the product therefore, there is a growing in growing interest in output capacitor-less LDOs that eliminate the large external output capacitors. Recent SoCs operate in near threshold voltage region for battery life in mobile environment, as a result digital LDOs (DLDO) which have feasibility in near threshold voltage has been reported.
In this paper, we propose a dynamic LDO that operates in near threshold voltage region and supports an output capacitor-less operation that can eliminate external capacitors and pads. Unlike DLDO, which operate in near threshold voltage region, the proposed LDO uses a single power transistor like an analog LDO. Voltage Difference to Time Converter (VDTC) is proposed substituting op-amp to enable operation in near threshold voltage region. Through the proposed VDTC, the proposed LDO have a ripple-less output. In addition, output impedance reduction loop is proposed to mitigate output voltage droop when sharp load transient occurs.
The proposed LDO was fabricated with 65nm LP CMOS process and its total area is 0.0834mm2. The proposed paper has a wide operating range and provides up to 30mA of output current at 0.6V input voltage. The proposed LDO consumes quiescent current of 0.1ฮผA at 1MHz clock and achieves 0.364fs FOM, improving prior art by 14x.์ 1 ์ฅ ์ ๋ก 1
1.1 ์ฐ๊ตฌ์ ๋ฐฐ๊ฒฝ 1
1.2 ๋
ผ๋ฌธ์ ๊ตฌ์ฑ 2
์ 2 ์ฅ Basics of LDO 4
2.1 Analog LDO 4
2.2 Digital LDO 6
2.3 Performance Metrics 7
2.3.1 Quiescent Current 7
2.3.2 Current Efficiency 8
2.3.3 Transient Response 8
2.3.4 Load Regulation 9
2.3.5 Line Regulation 9
์ 3 ์ฅ Design of proposed LDO 10
3.1 Design Consideration 10
3.2 Overall Architecture 11
3.3 Small Signal and Loop sta 14
3.4 Output Impedance Reduction Loop 16
3.5 Circuit Implementation 20
3.5.1 Voltage Differenc to Time Converter 20
3.5.2 Charge Pump and Power Transistor 23
3.5.3 Load Test Circuit 25
์ 4 ์ฅ Measurement 26
4.1 Measurement Setup 26
4.2 Die Photomicrograph 27
4.3 Load Transient Measurement 29
4.4 VREF Transient Measurement 31
4.5 Load and Line Regulation Measurement 32
4.6 Current Efficiency 34
4.7 Performance Summary 35
์ 5 ์ฅ Conclusion 37
์ฐธ๊ณ ๋ฌธํ 38
Abstract 41Maste
๋ ์ผ๋ฐํด ์ฃผ ์๋ ๋ฅด๊ฒ, Bla g4์ ์์ด ๋คํ์ฑ ๋ฐ ํฉํฐ๋ ๋จํธ๋ค์ IgE ๋ฐ์์ฑ
Dept. of Medical Science/์์ฌ[ํ๊ธ]
๋ฐํด๋ ์ฒ์์ด๋ ์ฌ๋ฌ ํธํก๊ธฐ ์๋ ๋ฅด๊ธฐ ์งํ์ ์ผ์ผํค๋ฉฐ, IgE์ ๊ฒฐํฉํ๋ ํญ์์ ๊ฐ์ง๊ณ ์๋ค. ์๋ ๋ฅด๊ฒ์ ํ๊ฒฝ์ , ์ ์ ์ ์์ธ์ ๋ฐ๋ฅธ ์ง์ญ์ ์ธ ์ฐจ์ด์ ๋ฐ๋ผ ๋จ๋ฐฑ์ง ์์ด์ ๋ค์ํ ๋ณ์ด๊ฐ ์๋ค. ์ด๋ฌํ ์ง์ญ์ ์ฐจ์ด์๋ ์ฐ์ธํ ๋ณ์ด์ฒด๋ฅผ ๊ด์ฐฐํ ์ ์๋ค. ์์์ ์๋ฏธ๋
ธ์ฐ ์นํ์ด๋ผ๋ ๋ฉด์ญ๋ฐ์์ ์๋นํ ์ํฅ์ ์ฃผ๊ธฐ ๋๋ฌธ์, ์ฐ์ธํ ๋ณ์ด์ฒด์ ์๋ ๋ฅด๊ธฐ ํญ์์ฑ์ ๊ฒฐ์ ํ๋ ๊ฒ์ ๋๋จํ ์ค์ํ๋ค. ๋ฐ๋ผ์ ๋ณธ ์ฐ๊ตฌ๋ฅผ ํตํด ํ๊ตญ์์ ์ฐ์ธํ Bla g 4์ ๋ณ์ด์ฒด๋ฅผ ์ฐพ์์ ์๋ฏธ๋
ธ์ฐ ์์ด์ ๋ถ์ํ๊ณ , E.coli ์์ ์ฌ์กฐํฉ ๋จ๋ฐฑ์ง์ ์์ฐํ์ฌ ๋ฐํด์ ๊ฐ์๋ ํ์ ํ์ฒญ์ผ๋ก๋ถํฐ IgE ๊ฒฐํฉ๋ฅ์ ์กฐ์ฌํ์๋ค. ๋ํ, ๋ฉด์ญ์น๋ฃ์ ์ค์ํ IgE binding epitope๋ฅผ ๊ท๋ช
ํ๊ธฐ ์ํด Bla g 4์ ํฉํฐ๋ ๋จํธ๋ค์ ํฉ์ฑํ์ฌ ELISA (Enzyme-linked immunosorbent assay)๋ฅผ ์ํํ์๋ค. ๋
์ผ๋ฐํด์ ์์ปท ์ฑ์ถฉ์ผ๋ก๋ถํฐ RT-PCR (reverse transcriptase polymerase chain reaction)์ ์ด์ฉํด Bla g 4 ์ ์ ์๋ฅผ ํด๋ก๋ํ์๋ค. ๊ธฐ์กด์ Bla g 4 DNA์์ด (U40767)๊ณผ ๋ค๋ฅธ ๋ณ์ด์ฒด(EF202172)๊ฐ ์กฐ์ฌ๋์ด ์๋ฏธ๋
ธ์ฐ ์์ด์ ๋ถ์ํ ๊ฒฐ๊ณผ, ๋ค์๊ณผ ๊ฐ์ด 13๊ฐ์ ์๋ฏธ๋
ธ์ฐ ์์ด์ด ์นํ๋์ด ์์๋ค: 8 (TโS), 13 (NโM), 62 (VโY), 64 (KโT), 69 (KโQ), 71 (KโN), 73 (KโR), 75 (TโA), 110 (EโD), 131 (IโL), 133 (FโL), 134 (SโT), and 135 (VโW). 51๊ฐ์ ํด๋ก ์ค์ ์ด 27๊ฐ์ ๋ณ์ด์ฒด๊ฐ ์กฐ์ฌ๋์์ผ๋ฉฐ, ๊ฐ์ฅ ๋น๋์๊ฐ ๋์ ๋ณ์ด์ฒด(14/51; 92.9%)๋ฅผ ํ๊ตญ์์ ์ฐ์ธํ ๋ณ์ด์ฒด(EF202172)๋ก ๊ฒฐ์ ํ์๋ค. ์ด๋ฅผ E.coli (DE3)์์ ๋ฐํ์์ผ ์ฌ์กฐํฉ ๋จ๋ฐฑ์ง์ ์์ฐํ๊ณ , ์ธ๋ธ๋์ค ๋ณ์์ ์๋ ๋ฅด๊ธฐ ํด๋ฆฌ๋์ ์ฐพ์ ๋ฐํด์๋ ๋ฅด๊ธฐ ํ์ 32๋ช
์ ํ์ฒญ์ ์ฐ๊ตฌ์ ์ด์ฉํ์๋ค. ๊ทธ ๊ฒฐ๊ณผ ์ด 32๋ช
์ ํ์๋ค ์ค 8๋ช
์ด ์ฌ์กฐํฉ Bla g 4์ ๊ฐํ๊ฒ ๋ฐ์ํ์ฌ IgE ๊ฒฐํฉ๋ฅ์ 25%์ ๋ํ๋ด์๋ค. ํด๋ก๋ํ Bla g 4๋ฅผ ๊ฐ๊ฐ 5๊ฐ์ ๋จํธ์ผ๋ก ๋๋์ด ๋ฐํํ๊ณ ์ฌ์กฐํฉ ๋จ๋ฐฑ์ง์ ์์ฐํ์๋ค. Bla g 4์ ๊ฐํ๊ฒ ๋ฐ์ํ๋ 4๋ช
์ ํ์ํ์ฒญ์ ์ด์ฉํ์ฌ ์ด๋ค์ IgE ๊ฒฐํฉ๋ฅ์ ์กฐ์ฌํ ๊ฒฐ๊ณผ, ๋จํธ1์ 0๋ช
(0%), ๋จํธ2๋2๋ช
(50%), ๋จํธ3์1๋ช
(25%), ๋จํธ4๋ 4๋ช
(100%), ๋จํธ5๋ 0๋ช
(0%)์ผ๋ก ์กฐ์ฌ๋์๋ค. ๋ฐ๋ผ์ IgE-binding epitopes ๋ถ์๋ ์๋ฏธ๋
ธ์ฐ ์์ด์์น 34~73, 78~113์ด๋ฉฐ, ์ฃผ ๊ฒฐํฉ๋ถ์๋ 118~152์ ์์นํ ๊ฒ์ผ๋ก ๋ํ๋ฌ๋ค.์ฌ์กฐํฉ ์๋ ๋ฅด๊ฒ์ ์ด์ฉํ Bla g 4์ linear B cell epitope์ ๋ํ ์ฐ๊ตฌ๋ ๋ณธ ์คํ์ ํตํ์ฌ ์ฒ์์ผ๋ก ๋ณด๊ณ ๋ ๊ฒ์ด๋ฉฐ, ์ด๋ ์๋ ๋ฅด๊ธฐ ํ์์ ์ ํํ ์ง๋จ๊ณผ ๋ฉด์ญ์น๋ฃ์ ๋ํ ๊ธฐ์ด์๋ฃ๋ก ํ์ฉ๋ ๊ฒ์ด๋ค.
[์๋ฌธ]Cockroaches are a major cause of asthma. Recombinant cockroach allergens have been identified and characterized, and different polymorphisms of major allergens have been described in various geographical regions. A change in the amino acid sequence of cockroach allergens could affect IgE binding capacities and T cell responses. In this study, reverse transcriptase-PCR was carried out to examine the sequence variations of the major German cockroach allergen Bla g 4, a member of the calycin protein family. A total of 27 different variants of Bla g 4 were identified by analysis of 51 clones obtained by RT-PCR. A Bla g 4 variant sequence appeared in 14 of the 51 clones (27.5%), indicating that it is a dominant form (EF202172). Differences between the dominant form (27.5%) obtained in this study and previously reported Bla g 4 (U40767) forms were found at 13 amino acid positions: amino acid position 8 (T to S), 13 (N to M), 62 (V to Y), 64 (K to T), 69 (K to Q), 71 (K to N), 73 (K to N), 75 (T to A), 110 (E to D), 131 (I to L), 133 (F to L), 134 (S to T), and 135 (V to W). Of note, the amino acid residues at 51-75 and 132-155 showed a high degree of sequence variation. These data suggest that Bla g 4 is highly polymorphic. A multiple amino acid sequence alignment with eight allergenic lipocalin family proteins was carried out by using the Clustal X program. Despite the probable structural similarity, the identity between the sequences was very low, showing only the two identical residues, Gly33 and Trp35 to the main conserved segment of the lipocalin family. Their influence on IgE-binding capacity and T cell responsiveness will be investigated in order to better understand immune responses to Bla g 4. The aim of this study was to investigate IgE reactivity to recombinant Bla g 4 (rBla g 4) in the sera of allergic patients and identify linear IgE binding epitopes. For protein expression, full-length Bla g 4 (EF202172) was divided into five overlapping peptide fragments (E1~E5; E1: aa 1-100, E2: aa 34-77, E3: aa 74-117, E4: aa 114-156, E5: aa 153-182). The full-length and five peptide fragments of Bla g 4 were generated by PCR and over-expressed in E. coli BL21 (DE3). The IgE binding reactivities of the full-length and peptide fragments were measured by enzyme linked immunosorbent assay (ELISA) using 32 serum samples of from patients with cockroach allergies. The sera of 8 patients (25%) reacted with rBla g 4, a prevalence significantly lower than the 40~60% reported previously by Arruda et al (1996). Four sera (100%) showed IgE-binding reactivity to full-length and peptide fragment 4, 3 sera (80%) reacted with peptide fragment 2, one (20%) serum sample reacted with peptide fragment 3. The ELISA results from the overlapping recombinant fragments localized the epitope region to amino acids 34~73 and 78~113, with the major IgE epitope of Bla g 4 localized to amino acid residues 118~152 of the C-terminus. Heterogeneity in IgE responses to Bla g 4 in individual patients was also observed, correlating with the finding that the most allergens have multiple IgE-binding sites which are at least partly due to the polyclonal nature of the immune response to protein allergens. Out results may provide fundamental bases for developing effective diagnostics and therapeutics for treating cockroach allergies.ope