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      參數(shù)資料
      型號: MAX1630EAI
      廠商: MAXIM INTEGRATED PRODUCTS INC
      元件分類: 穩(wěn)壓器
      英文描述: Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers
      中文描述: SWITCHING CONTROLLER, 300 kHz SWITCHING FREQ-MAX, PDSO28
      封裝: 5.30 MM, 0.65 MM PITCH, SSOP-28
      文件頁數(shù): 18/28頁
      文件大?。?/td> 237K
      代理商: MAX1630EAI
      M
      Multi-Output, Low-Noise Power-S upply
      Controllers for Notebook Computers
      18
      ______________________________________________________________________________________
      Kool-Mu is a registered trademark of Magnetics Div., Spang & Co.
      sistor can be added. Figure 6’s circuit delivers more
      than 200mA. Total output current is constrained by the
      V+ input voltage and the transformer primary load (see
      Maximum 15V V
      DD
      Output Current vs. Supply Voltage
      graphs in the Typical Operating Characteristics).
      __________________Design Proc edure
      The three predesigned 3V/5V standard application cir-
      cuits (Figure 1 and Table 1) contain ready-to-use solu-
      tions for common application needs. Also, two standard
      flyback transformer circuits support the 12OUT linear
      regulator in the Applications Information section. Use
      the following design procedure to optimize these basic
      schematics for different voltage or current require-
      ments. But before beginning a design, firmly establish
      the following:
      Maximum input (battery) voltage, V
      IN(MAX)
      . This
      value should include the worst-case conditions, such
      as no-load operation when a battery charger or AC
      adapter is connected but no battery is installed.
      V
      IN(MAX)
      must not exceed 30V.
      Minimum input (battery) voltage, V
      IN(MIN)
      . This
      should be taken at full load under the lowest battery
      conditions. If V
      IN(MIN)
      is less than 4.2V, use an external
      circuit to externally hold VL above the VL undervoltage
      lockout threshold. If the minimum input-output differ-
      ence is less than 1.5V, the filter capacitance required to
      maintain good AC load regulation increases (see Low-
      Voltage Operationsection).
      Induc tor V alue
      The exact inductor value isn’t critical and can be freely
      adjusted to make trade-offs between size, cost, and
      efficiency. Lower inductor values minimize size and
      cost, but reduce efficiency due to higher peak-current
      levels. The smallest inductor is achieved by lowering
      the inductance until the circuit operates at the border
      between continuous and discontinuous mode. Further
      reducing the inductor value below this crossover point
      results in discontinuous-conduction operation even at
      full load. This helps lower output filter capacitance
      requirements, but efficiency suffers due to high I
      2
      R
      losses. On the other hand, higher inductor values mean
      greater efficiency, but resistive losses due to extra wire
      turns will eventually exceed the benefit gained from
      lower peak-current levels. Also, high inductor values
      can affect load-transient response (see the V
      SAG
      equa-
      tion in the Low-Voltage Operation section). The equa-
      tions that follow are for continuous-conduction
      operation, since the MAX1630 family is intended mainly
      for high-efficiency, battery-powered applications. See
      Appendix A in Maxim’s Battery Management and DC-
      DC Converter Circuit Collection for crossover-point and
      discontinuous-mode equations. Discontinuous conduc-
      tion doesn’t affect normal Idle Mode operation.
      Three key inductor parameters must be specified:
      inductance value (L), peak current (I
      PEAK
      ), and DC
      resistance (R
      DC
      ). The following equation includes a
      constant, LIR, which is the ratio of inductor peak-to-
      peak AC current to DC load current. A higher LIR value
      allows smaller inductance, but results in higher losses
      and higher ripple. A good compromise between size
      and losses is found at a 30% ripple-current to load-
      current ratio (LIR = 0.3), which corresponds to a peak
      inductor current 1.15 times higher than the DC load
      current.
      V
      V
      OUT
      IN(MAX)
      (
      where: f = switching frequency, normally 200kHz or
      300kHz
      I
      OUT
      = maximum DC load current
      LIR = ratio of AC to DC inductor current, typi-
      cally 0.3; should be selected for >0.15
      The nominal peak inductor current at full load is 1.15 x
      I
      OUT
      if the above equation is used; otherwise, the peak
      current can be calculated by:
      V
      PEAK
      LOAD
      The inductor’s DC resistance should be low enough that
      R
      DC
      x I
      PEAK
      < 100mV, as it is a key parameter for effi-
      ciency performance. If a standard off-the-shelf inductor
      is not available, choose a core with an LI
      2
      rating greater
      than L x I
      PEAK
      2 and wind it with the largest-diameter
      wire that fits the winding area. For 300kHz applications,
      ferrite core material is strongly preferred; for 200kHz
      applications, Kool-Mu
      (aluminum alloy) or even pow-
      dered iron is acceptable. If light-load efficiency is unim-
      portant (in desktop PC applications, for example), then
      low-permeability iron-powder cores, such as the
      Micrometals type found in Pulse Engineering’s 2.1μH
      PE-53680, may be acceptable even at 300kHz. For
      high-current applications, shielded-core geometries,
      such as toroidal or pot core, help keep noise, EMI, and
      switching-waveform jitter low.
      I
      = I
      +
      (V
      - V
      2 x f x L x V
      OUT
      IN(MAX)
      OUT
      IN(MAX)
      )
      L =
      - V
      V
      x f x I
      x LIR
      OUT
      IN(MAX)
      OUT
      )
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      相關(guān)代理商/技術(shù)參數(shù)
      參數(shù)描述
      MAX1630EAI-T 功能描述:DC/DC 開關(guān)控制器 RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
      MAX1630EVKIT-SO 功能描述:DC/DC 開關(guān)控制器 Evaluation Kit for the MAX1630 MAX1631 MAX1632 RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
      MAX1631AEAI 功能描述:DC/DC 開關(guān)控制器 RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
      MAX1631AEAI+ 功能描述:DC/DC 開關(guān)控制器 Multi-Out Low-Noise Power-Supply Ctlr RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
      MAX1631AEAI+T 功能描述:DC/DC 開關(guān)控制器 Multi-Out Low-Noise Power-Supply Ctlr RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK