Battery powered applications that have a signifi cantamount of time in standby mode, require electrical circuitsto operate with a low quiescent current to preserve batterylife. The LTC3835 synchronous step-down controlleris an excellent solution with its ultralow quiescent current(80μA). Other features make it uniquely qualifi ed tosatisfy the needs of automotive applications. A wide 4Vto 36V input voltage range protects the supply againsthigh input voltage transients and is compatible with lowvoltage cold crank conditions. The constant frequencycurrent-mode architecture with high-side inductor current
上傳時間: 2013-11-20
上傳用戶:stewart·
Traditionally, an Electronic Circuit Breaker (ECB) comprisesa MOSFET, a MOSFET controller and a current senseresistor. The LTC®4213 does away with the sense resistorby using the RDS(ON) of the external MOSFET. The resultis a simple, small solution that offers a signifi cant lowinsertion loss advantage at low operating load voltage.The LTC4213 features two circuit breaking responses tovarying overload conditions with three selectable tripthresholds and a high side drive for an external N-channelMOSFET switch.
上傳時間: 2014-03-02
上傳用戶:lixinxiang
Automotive batteries, industrial power supplies, distributedsupplies and wall transformers are all sources ofwide-ranging high voltage inputs. The easiest way to stepdown these sources is with a high voltage monolithicstep-down regulator that can directly accept a wide inputrange and produce a well-regulated output. The LT®3493accepts inputs from 3.6V to 36V and LT3481 acceptsinputs from 3.6V to 34V. Both provide excellent lineand load regulation and dynamic response. The LT3481offers a high effi ciency solution over a wide load range andkeeps the output ripple low during Burst Mode® operationwhile the LT3493 provides a tiny solution with minimalexternal components. The LT3493 operates at 750kHzand the LT3481 has adjustable frequency from 300kHzto 2.8MHz. High frequency operation enables the use ofsmall, low cost inductors and ceramic capacitors.
上傳時間: 2014-12-24
上傳用戶:Pzj
The LTC®3562 quad output step-down regulator is designedfor multicore handheld microprocessor applications thatoperate from a single Li-Ion battery. Its four monolithic, higheffi ciency buck regulators support Intel’s mobile CPU P-Stateand C-State energy saving operating modes. The outputvoltages are independently controllable via I2C, and eachoutput can be independently started and shut down. Designerscan choose from power saving pulse-skipping mode orBurst Mode® operation, or select low noise LDO mode. Thespace-saving LTC3562 is available in a 3mm × 3mm QFNpackage and requires few external components.
上傳時間: 2013-10-07
上傳用戶:1583060504
The LTC®3569 is a compact power solution for handhelddevices. Its tiny 3mm × 3mm QFN package includesthree buck regulators with individually programmableoutput voltages. One regulator supports load currentsup to 1200mA, while the other two support currents to600mA. Two regulators can be paralleled for increasedload capability. Each current-mode regulator is internallycompensated with excellent load and line regulation. Acomplete 2- or 3-output solution requires a minimumof external passive components.
上傳時間: 2013-10-11
上傳用戶:yxgi5
The LTC3546 is a dual output current mode buck regulatorwith fl exible output current partitioning. Beyondthe advantages normally associated with dual outputregulators (reduced size, cost, EMI and part count, withimproved effi ciency), the LTC3546’s outputs can bepartitioned for either 3A and 1A outputs, or two 2A outputs.This increases its application range and simplifi esmultiple supply rail designs. A confi gurable Burst Mode®clamp for each output sets the current transition levelbetween Burst Mode operation and forced continuousconduction mode to optimize effi ciency over the entireoutput range. An adjustable switching frequency up to4MHz and internal power MOSFET switches allow forsmall and compact footprints.
上傳時間: 2013-11-04
上傳用戶:yxgi5
The LTC®3610 is a high power monolithic synchronousstep-down DC/DC regulator that can deliver up to 12Aof continuous output current from a 4V to 24V (28Vmaximum) input supply. It is a member of a high currentmonolithic regulator family (see Table 1) that featuresintegrated low RDS(ON) N-channel top and bottomMOSFETs. This results in a high effi ciency and highpower density solution with few external components.This regulator family uses a constant on-time valleycurrent mode architecture that is capable of operatingat very low duty cycles at high frequency and with veryfast transient response. All are available in low profi le(0.9mm max) QFN packages.
上傳時間: 2013-11-07
上傳用戶:moerwang
為了改變目前電網現場作業管理的變電巡檢、變電檢修試驗、輸電線路巡檢檢修等管理系統各自獨立運行,信息不能共享,功能、效率受限,建設和維護成本高的現狀,提出了采用B/S+C/S構架模式,將各現場作業管理模塊和生產MIS(管理系統)集成為一體的現場作業管理系統的設計方案,做到各子系統和生產MIS軟硬資源共享,做到同一數據唯一入口、一處錄入多處使用。各子系統設備人員等基礎信息來源于生產管理系統,各子系統又是生產管理系統的作業數據、缺陷信息的重要來源。經過研究試用成功和推廣應用,目前該系統已在江西電網220 kV及以上變電站全面應用。 Abstract: In order to improve the status that the substation field inspection system, substation equipments maintenance and testing system, power-line inspection and maintenance system are running independent with each other. They can?蒺t share the resource information which accordingly constrains their functions and efficiency, and their construction and maintenance costs are high. This paper introduces a field standardized work management system based on B/S+C/S mode, integrating all field work management systems based on MIS and share the equipments and employee?蒺s data of MIS,the field work data of the sub systems are the source information of MIS, by which the same single data resouce with one-time input can be utilized in multiple places. After the research and testing, this system is triumphantly using in all 220kV and above substations in Jiangxi grid.
上傳時間: 2013-11-15
上傳用戶:han_zh
光伏發電是未來新能源發電重要方向之一,而光伏變流器是光伏發電系統的核心。介紹一種基于微網理念的光伏變流器設計。以該變流器為核心的光伏發電系統可以看做一個小型的微網系統。該系統能根據外部電網情況,工作于并網模式和離網模式。介紹了該系統的各個組成部件的設計以及變流器主電路部分器件的選型。最后,由實驗樣機進行測試。試驗結果驗證了電路拓撲結構及控制方案的可行性,也說明了系統參數設計方法的正確性。 Abstract: Solar Photovoltaic generation is an important direction of new energy power generation in the future,while photovoltaic converter is the core of photovoltaic generation system. This paper deals with a study on photovoltaic inverter based on the concept of microgrid. This paper describes a system whose core component is the photovoltaic inverter,can work on grid-connected mode or run independently according to the external situation. The paper simply describes the main components of the system. At last,the prototype was produced and tested. Test result has proved feasibility of circuit topology structure and controlling scheme and shown correctness of system parameters.Key words: PV inverter; microgrid; off-grid; storage battery
上傳時間: 2014-12-24
上傳用戶:Shaikh
鎖定放大是微弱信號檢測的重要手段。基于相關檢測理論,利用開關電容的開關實現鎖定放大器中乘法器的功能,提出開關電容和積分器相結合以實現相關檢測的方法,并設計出一種鎖定放大器。該鎖定放大器將微弱信號轉化為與之相關的方波,通過后續電路得到正比于被測信號的直流電平,為后續采集處理提供方便。測量數據表明鎖定放大器前級可將10-6 A的電流轉換為10-1 V的電壓,后級通過帶通濾波器級聯可將信號放大1×105倍。該方法在降低噪聲的同時,可對微弱信號進行放大,線性度較高、穩定性較好。 Abstract: Lock-in Amplifying(LIA)is one of important means for weak signal detection. Based on cross-correlation detection theory, switch in the swithched capacitor was used as multiplier of LIA, and a new method of correlation detection was proposed combining swithched capacitor with integrator. A kind of LIA was designed which can convert the weak signal to square-wave, then DC proportional to measured signal was obtained through follow-up conditioning circuit, providing convenience for signal acquisition and processing. The measured data shows that the electric current(10-6 A) can be changed into voltage(10-1 V) by LIA, and the signal is magnified 1×105 times by cascade band-pass filter. The noise is suppressed and the weak signal is amplified. It has the advantages of good linearity and stability.
上傳時間: 2013-11-29
上傳用戶:黑漆漆