ADP1821:  Step-Down DC-to-DC Controller

The ADP1821 is a versatile and inexpensive, synchronous, pulse-width-modulated (PWM), voltage-mode, step-down controller. It drives an all N-channel power stage to regulate an output voltage as low as ...More

ADP1821:  Step-Down DC-to-DC Controller

Product Description

The ADP1821 is a versatile and inexpensive, synchronous, pulse-width-modulated (PWM), voltage-mode, step-down controller. It drives an all N-channel power stage to regulate an output voltage as low as 0.6 V. The ADP1821 can be configured to provide output voltages from 0.6 V to 85% of the input voltage and is sized to handle large MOSFETs for point-of-load regulators.

The ADP1821 is well suited for a wide range of high power applications, such as DSP and processor core power in telecommunications, medical imaging, high performance servers, and industrial applications. It operates from a 3.7 V to 5.5 V supply with a power input voltage ranging from 1.0 V to 24 V.

The ADP1821 operates at a pin-selectable, fixed switching frequency of either 300 kHz or 600 kHz, minimizing external component size and cost. For noise sensitive applications, it can be synchronized to an external clock to achieve switching frequencies between 300 kHz and 1.2 MHz. The ADP1821 includes soft start protection to limit the inrush current from the input supply during startup, reverse current protection during soft start for precharged outputs, as well as a unique adjustable lossless current-limit scheme utilizing external MOSFET sensing.

The ADP1821 operates over the –40°C to +125°C junction temperature range and is available in a 16-lead QSOP.

Applications

  • Telecommunications and networking systems
  • Set-top boxes
  • Printers
  • Servers
  • Medical imaging systems
  • Microprocessor and DSP core power supplies
  • Mobile communication base stations

    • Data Sheet, Rev. C, 4/07

    Features

    • Wide power-input voltage range: 1 V to 24 V
    • Chip supply voltage range: 3.7 V to 5.5 V
    • Wide output voltage range: 0.6 V to 85% of input voltage
    • 1% accuracy, 0.6 V reference voltage
    • All N-channel MOSFET design for low cost
    • Fixed-frequency operation 300 kHz, 600 kHz, or synchronized operation up to 1.2 MHz
    • No current sense resistor required
    • Power-good output
    • Programmable soft start with reverse current protection
    • Soft start, thermal overload, current-limit protection
    • Undervoltage lockout
    • 10 μA shutdown supply current

    Diagrams

    ADP1821 Diagram
    Circuit Diagram for ADP1821

    技术指标

    Vin Range 3.7V-5.5V
    Vout Adj
    Step Up No
    Shutdown Y
    Pkg QSOP-16

    浏览其他的产品

    ADP1043 - 适合隔离电源应用的数字控制器

    订阅新产品资料
    Part# Vin Range Pwr Stage Vin Vout Adj Options Multi-Output Shutdown Current Supply Current (max) Switching Frequency Iout (max) Synchronous Step Down Step Up Pkg Product Description Price* (1000-4999)
    ADP1621 2.9V-5.5V As Low As 1V Lossless ISens@<30V Vout, Resistor ISens@>30V No 10µA 3mA 100 KHz - 1.5 MHz - No No Yes MSOP-10 Constant-Frequency, Current-Mode, Step-Up DC/DC Controller $1.32
    ADP1821 3.7V-5.5V 1V-24V 0.6V to 85% PwrStgVin No 10µA 2mA 300 kHz -600 kHz, Sync up to 1 MHz 20A Yes Yes No QSOP-16 20 A Step-Down DC-DC Controller $1.37
    ADP1822 3.7V-5.5V 1V-24V 0.6V to 85% PwrStgVin No 10µA 2mA 300 kHz-600 kHz; Sync up to 1 MHz 20A Yes Yes No QSOP-24 20 A, PWM, Step-Down DC-DC Controller with Margining and Tracking $1.42
    ADP1823 3.7V-20V 1V-24V 0.6V to 85% PwrStgVin Yes 20µA 3mA 300 kHz-600 kHz, Sync up to 1 MHz 20A Yes Yes No LFCSP-32 Versatile Dual, Interleaved Synchronous PWM Buck Controller w/ Tracking $2.13
    ADP1828 3.0V-18V 1V-24V 0.6V to 85% PwrStgVin No 15µA 3mA 300 kHz to 600 kHz - Yes Yes No QSOP-20 Synchronous Buck PWM, Step-Down, DC-to-DC Controller $1.52
    ADP1829 3.0V-18V 1V-24V 0.6V to 85% PwrStgVin Yes 20µA 3mA 300 kHz-600 kHz, Sync up to 1 MHz 20A Yes Yes - LFCSP-32 Dual, Interleaved, Step-Down DC-to-DC Controller w/ Tracking $2.13
    ADP1864 3.15V-14V 3.15V-14V 0.8V to Vin No 15µA 350µA 580 kHz 5A No Yes No TSOT-6 5A, Constant Frequency, Current-Mode Step-Down DC/DC Controller in TSOT $1.06

    * The pricing listed here is provided only for budgetary purposes as recommended list price in U.S. Dollars in the United States ex factor per unit for the stated volume. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.
    ** Pricing is currently unavailable. Click on the product number to see the Product Page for additional information.

    价格、封装以及购买

    Help

    产品型号
    产品型号是指能够购买或者索取样片的某类产品的具体型号。

    产品状态
    产品状态指该产品当前的生存周期。它指下面四个阶段之一：
    • 预发布：该产品型号尚未投入正式生产，但是可以提供样片。
    • 生产：该产品型号目前已在生产，可以购买和索取样片。
    • 停产前限时购买：该型号已经计划停产，但仍然可以在限定的时间内购买。
    • 停产：该型号产品已经停产，不再提供。本表格中列出的其它型号产品仍可以供货（如果这些型号不处于停产状态）。
    封装说明
    这种集成电路（IC）的封装说明，例如：DIP，SOIC和BGA封装。评估板是一块用来演示器件性能的试验板，该器件也包含在该评估板上。

    欲详细了解封装图和化学成份请访问：  封装网页

    引脚数
    引脚数是指该器件的引脚、球状焊点或焊盘的数量。产品技术资料中提供引脚排列图和引脚功能描述。

    温度范围
    这是指该器件允许的工作温度范围。以下为所规定的三种温度范围：
    • 民用温度范围：0 ºC～＋70 ºC
    • 军用温度范围：－55ºC ～＋125ºC
    • 工业用温度范围：不同型号的产品的温度范围可能不同。欲了解更多信息，请查阅产品技术资料。
    • 汽车工作温度范围：-40 ℃～ +125 ℃
    报价
    这里所列出的美国报价单仅供预算参考，指美元报价（规定订量的每片美元，美国离岸价），如有修改不再另行通知。由于地区关税、商业税、汇率及手续费原因，国际报价可能不同。对于特殊批量报价，请与您当地的ADI公司办事处或代理商联络。对于评估板和套件的报价是指一个单位价格。

    Production Availability
    This is the date Analog Devices, Inc. anticipates that the product will ship from the warehouse. Most orders ship within 48 hours of this date.Once an order has been placed,