Analysis and design of constant-current control chip for driving high-power LED

随着全球能源短缺，节能减排要求不断提高的时代背景之下，各国都在大力发展绿色照明产业。LED照明作为一种新型节能、环保技术，迅速成为政府和企业聚光的焦点。由于LED发光效率高，从生产过程到使用过程几乎全无污染，使用寿命却延长数十倍，成为近年来全球最具发展前景的高新技术之一，半导体照明技术正在改变照明技术百年的历史。 虽然LED的优势非常明显，但是也有其缺点存在：均一性差。这就给LED驱动提出了较高的要求，为了解决LED的这一缺点，恒流驱动是最理想的选择。由于LED光源的应用场合非常广泛，所以，针对不同的要求设计出不同性能的驱动控制器成为业内市场的发展趋势。 本文在介绍了LED的各项特性，行业...Due to the shortage and urgent requirement of energy conservation, each country is promoting the green lighting application.LED ,as a new energy-saving and environment-protecting technology, performs a role so irreplaceable that government and corporations all focus on it. And LED has high light-emitting efficiency, almost pollution-free from the manufacture to use up and tens of times than usual ...学位：工程硕士院系专业：信息科学与技术学院电子工程系_集成电路学号：2312009115268

A BiCMOS-based bandgap reference circuit with high PSRR and precision

介绍了一种bICMOS工艺制作的高电源抑制比和高精确度的带隙基准电压源,其输出电压为1.2 V,在-40℃--80℃范围内有较好的温度特性,温度漂移系数为9.8x10-6℃-1。采用电压负反馈原理和减少耦合电容的方法,使电路具有高的电源抑制比,并且电路结构简单,匹配性好。采用HSPICE工具对电路进行了仿真,验证了设计的正确性。该电路能广泛用于在电源环境恶劣的场合下工作的集成电路中。This paper describes the design of a bandgap reference circuit with high Power Supply Rejection Ratio(PSRR) and high precision.The circuit can output a reference voltage of 1.2 V and bears a temperature coefficient of 9.8×10-6 ℃-1 between-40 ℃ and 80 ℃.The circuit features high PSPR,simple circuit structure and excellent matching performance by using a negative-feedback loop and reducing the coupling capacitance.The correctness of the circuit design is verified through the simulation in Hspice.The circuit can be widely used in the integrated circuits working under harsh power environment

2007年厦门市湖里区伤害监测结果分析

[目的]了解厦门市湖里区伤害病例发生的情况,为制订干预措施提供科学依据。[方法]用分层随机抽样方法,抽取二级、三级医院各1所为哨点监测医院。[结果]全年共监测病例36 845例,男∶女为2.3∶1;导致伤害前3位依次为钝器伤(32.6%)、刀/锐器伤(24.9%)和跌倒/坠落(22.3%);主要为生产运输设备操作及有关人员(35.2%)、商业服务业人员(15.3%)和办事和有关人员(12.2%);伤害主要发生在5～10月(56.9%);日发生的高峰时间为7～12时和17～20时(61.0%)。[结论]青壮年是伤害防治的重点人群,预防和控制职业伤害是干预的重点,加强生产安全保护措施和创造安全的环境是主要的预防措施

Iodine nutrition status of pregnant women in Xiamen City after adjusting iodized salt concentration

目的掌握gb 26878-2011《食用盐碘含量》标准执行后,厦门市妊娠期妇女碘营养状况,为卫生策略的制定提供依据。方法选择厦门市翔安区新店镇为调查点,调查妊娠期妇女食用新标准碘盐前后家中的碘盐覆盖率、合格碘盐食用率、尿碘、尿比重水平。结果基线调查及新标准实施后第1到第5次评估,妊娠期妇女家庭碘盐覆盖率均达到100%,盐碘中位数分别为27.8、25.7、24.3、23.7、24.3和25.8 Mg/kg,5次评估的碘盐含量均比基线调查明显减少(均P0.05);基线调查及5次评估测得尿比重均数分别为1.0123、1.0153、1.0180、1.0143、1.0141和1.0132。第1、2、3次评估的尿比重水平均高于基线调查尿比重水平(均P0.05)。结论新标准实施后,妊娠期妇女家中食盐含碘量显著减少,新标准实施前后妊娠期妇女均处于碘营养不足状态,需加强该人群碘营养,保障下一代健康。[Objective]To understand the iodine nutrition status of pregnant women after implementation of‘Edible Salt Iodine Content'( GB26878-2011),and provide evidence for developing health policy.[Methods]The coverage rate of iodized salt,proportion of households using adequately iodized salt,urine-iodine and specific gravity of urine in pregnant women were investigated in Xindian Town of Xiang'an District in Xiamen City which was chosen as the research spot.[Results]In the baseline investigation and during the first-fifth self-assessment stage after carrying out the new standards,the coverage rates of iodized salt were all 100% and the iodine median value in pregnant women was 27.8 mg / kg,25.7 mg / kg,24.3 mg / kg,23.7 mg / kg,24.3 mg / kg and25.8 mg / kg,respectively.The iodine contents in the first-fifth selfassessment stage were all less than that in the baseline survey( all P 0.05).The proportion of urine in pregnant women in the baseline investigation and the first- fifth self-assessment stage was 1.012 3,1.015 3,1.018 0,1.014 3,1.014 1 and 1.013 2 respectively.The proportions of urine in the first-third self-assessment stage were all higher than the baseline survey( all P 0.05).[Conclusion]After the implementation of the new standard,the iodinated content in salt in pregnant households has been reduced significantly.But the pregnant women are in iodine malnutrition before and after implementation of the new standard.It is necessary to strengthen the iodine nutrition for the health of the fetus.福建省科技厅自然基金面上项目(项目编号:2012D046); 厦门市科技局科技计划项目(项目编号:3502Z20124057

Investigation on the iodine status among the population in rural and urban areas of Xiamen in 2013

目的了解碘盐新标准实施后农村和城市人群的碘营养现况,为有效落实科学补碘防控策略提供依据。方法在农村和城市调查点各抽取1个镇的1个村,在每个村采集自来水厂出厂水和末梢水各2份;抽取30户以上居民,采集各户家庭食用盐,用3日称量法测算各户居民人均食盐摄入量;抽取18-45岁成人50名以上,采集尿样。在抽中的镇随机选择8-10岁儿童(男女各半)、孕妇和哺乳期妇女各50名以上,采集尿样。测定盐碘、尿碘和水碘含量。结果农村和城市自来水末梢水水碘含量均值分别为4.5μg/L和6.0μg/L;居民人均每日食用盐摄入量中位数分别为7.0和5.6g;8~10岁儿童尿碘中位数分别为152.0和181.2μg/L;哺乳妇尿碘中位数分别为108.3和107.7μg/L;18-45岁成人尿碘中位数分别为121.1和147.4μg/L;孕妇尿碘中位数分别为116.0和112.2μg/L,尿碘含量低于150μg/L的比例分别达67.9%和64%;除农村人均每日食用盐摄入量高于城市,农村18-45岁成人尿碘水平低于城市外,其他指标农村和城市间差异无显著性。结论厦门市仍是缺碘地区,在现有碘盐标准下,8-10岁儿童、18-45岁成人、哺乳期妇女的碘营养处于适宜水平,但孕妇的碘营养不足,要开展针对孕期人群的碘营养监测和指导,杜绝碘缺乏所造成的危害。Objective To gain knowledge of the iodine status among the population in rural and urban areas after the implement of new standard for edible salt and to provide scientific evidence for the initiative of the iodine supplement strategy. Method 1 village / community was selected randomly from rural and urban area as research site respectively. 2 samples of treated water and tap water were collected respectively in both sites, 30 + houses were enrolled randomly and edible salt samples were collected. 3days weighed record was employed to estimate average salt daily intake. Urine sample was collected from 50 + adults aged from 18 to 45. Identical sample was also collected from 50 + children aged from 8 to 10( same amount of subjects in both genders),pregnant women, and lactating women respectively. Iodine level of water, salt, and urine was determined by laboratory assay.Results The iodine concentration of tap water in rural and urban areas was 4. 5 μg / L and 6. 0 μg / L,respectively. The median of average iodine intake in rural and urban areas was 7. 0 g and 5. 6 g, respectively. The median in urine iodine was 152. 0 μg / L and 181. 2 μg / L,respectively. This measurement in lactating women was 108. 3 μg / L and 107. 7 μg / L,respectively. And it was121. 1 μg / L and 147. 4 μg / L in adults aged 18 to 45, respectively. As for the pregnant women, the iodine level reached 116. 0μg /L and 112. 2 μg /L,respectively. The proportion of subjects has urine iodine level less than 150 μg /L reached 67. 9 % and 64 %, respectively. The average salt intake in rural area was higher than urban significantly, and the urine iodine level in adults aged 18 to 45 from rural area was significantly lower than urban. No significance was found in other comparison. Conclusion Through our investigation,Xiamen is still an iodine deficiency area. Under the implement of new edible salt standard, the iodine status in children aged 8 to 10, adults aged 18 to 45 and lactating women was adequate, however, we found that pregnant women enrolled in our study have iodine deficiency in some degrees. Therefore the iodine surveillance and dietary guidance should be performed among pregnant women to eliminate the harm caused by iodine deficiency

沿海产盐区与非产盐区8～10岁儿童碘营养与智力水平分析

目的了解和比较沿海产盐区和非产盐区8~10岁儿童碘营养状况与智力水平,为采取针对性防治措施提供依据。方法选择产盐区翔安区和非产盐区集美区的小学为调查点,8~10岁儿童为调查对象,调查其家中碘盐食用情况、尿碘含量、甲状腺肿大情况和智商水平。结果产盐区和非产盐区儿童合格碘盐食用率分别为81.5%和98.6%;甲状腺肿大率分别为3.0%和0.7%,尿碘中位数分别为202.8μg/L和238.4μg/L,<50μg/L的比例分别为3.5%和1.0%。产盐区8~10岁儿童智商均明显低于非产盐区儿童;产盐区8岁儿童智商明显高于9岁和10岁儿童;非产盐区8岁儿童智商明显高于9岁和10岁儿童,9岁儿童智商明显高于10岁儿童。结论补碘能提高儿童智商,降低智力损害。要坚持食用碘盐,开展对孕妇、哺乳妇的碘营养监测

厦门市碘缺乏病防治现状与对策

[目的]了解碘缺乏病防治现状,探讨今后防治措施与策略。[方法]采用容量比例概率法抽查学生甲状腺大小、尿碘、盐碘,开展加工厂盐、居民户盐及盐民自用盐的盐碘含量监测。[结果]查2525名8～10岁学生,甲状腺肿大率为3.72%(触诊法),自1995年以来呈逐年下降趋势,合格碘盐食用率89.66%,碘盐覆盖率90.72%,尿碘中位数为246.40μg/L;加工厂盐合格率为99.15%,居民户碘盐覆盖率为95.25%、合格碘盐食用率为94.10%,盐民自供盐10月份后合格碘盐食用率已达到90%以上。[结论]我市继续保持在实现消除碘缺乏病阶段目标,但今后应坚持开展病情监测和坚持防制措施不松懈

沿海产盐区与非产盐区妊娠期妇女碘营养状况及甲状腺功能水平分析

目的了解福建沿海产盐区与非产盐区妊娠期妇女碘营养状况及其甲状腺功能水平,为防治碘缺乏病提供科学依据。方法选择产盐区翔安区和非产盐区集美区为调查点,每个点随机抽取60名以上妊娠期妇女作为调查对象,采集孕妇的家中盐样、尿样及血样,分别测定盐碘、尿碘及血清甲状腺激素。结果产盐区与非产盐区孕妇合格碘盐食用率分别为81.69%和100.00%;产盐区与非产盐区孕妇尿碘的中位数分别为120.55μg/L和153.35μg/L,尿碘孕中期>孕晚期;产盐区与非产盐区孕妇的甲状腺过氧化物酶抗体(thyroid peroxidase antibody,TPOAb),抗甲状腺球蛋白抗体(antithyroid glubulin antibody,TgAb),总三碘甲状腺原氨酸(total-triiodothyronine,TT3),总甲状腺素(total thyroxine,TT4),游离三碘甲状腺原氨酸(free triiodothyronine,FT3),游离甲状腺素(free thyroxine,FT4),促甲状腺激素(thyroid stimulating hormone,TSH),甲状腺球蛋白(tryroglobulin,Tg)中位数均在正常范围,产盐区与非产盐区孕妇的FT3、FT4、TSH之间差异均有统计学意义,产盐区孕妇的FT3、FT4均低于非产盐区,而产盐区孕妇的TSH则高于非产盐区。结论孕妇是易缺碘人群,产盐区孕妇相对非产盐区碘缺乏更为严重。应对孕妇开展常规碘营养和甲状腺功能监测,进一步做好碘营养知识的宣传教育工作,控制碘缺乏病的发生

沿海产盐区与非产盐区18～45岁人群碘营养状况及甲状腺功能水平研究

目的掌握厦门市沿海产盐区与非产盐区居民盐碘、18～45岁人群碘营养和甲状腺功能水平状况,为采取针对性的防治措施提供依据。方法选择沿海产盐区翔安区和非产盐区集美区为调查点,调查居民合格碘盐食用率、18～45岁育龄期妇女和男性尿碘水平、甲状腺激素水平和海带、紫菜的摄入习惯。结果产盐区和非产盐区盐碘中位数均为27.21 mg/kg,合格碘盐食用率分别为95.33%和96.33%;18～45岁男性尿碘中位数分别为206.55μg/L和232.95μg/L,尿碘<100μg/L的比例分别为20.97%和10%;18～45岁育龄期妇女尿碘中位数分别为176.95μg/L和227.70μg/L,尿碘<100μg/L的比例分别为21.67%和25%;产盐区和非产盐区18～45岁男性和育龄期妇女的甲状腺激素TSH、Tg、FT3、FT4、TPOAb、TT3、TT4中位数均在正常值范围内;产盐区18～45岁男性的甲状腺功能亢进阳性率为3.4%、育龄期妇女的甲状腺功能减退和亚临床甲状腺减退症的阳性率均为1.67%,而非产盐区均为0。产盐区和非产盐区18～45岁男性和育龄期妇女中均有一定比例易患甲状腺免疫性疾病的人群。每月食用海带、紫菜的次数≥4次、1～3次和<1次的人尿碘组间比较无统计学差异。结论产盐区和非产盐区18～45岁男性和育龄期妇女碘营养总体处于适宜状态,应坚持食盐加碘措施,对育龄期妇女在婚前体检时开展常规碘营养水平和甲状腺功能检测