Add to Signal Chain Designer

ADP1821:  Step-Down DC-to-DC Controller

Product Details


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

FEATURES and BENEFITS

  • 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

Circuit Diagram for ADP1821

Documentation

Title Content Type File Type
ADP1821: Step-Down DC-to-DC Controller Data Sheet (Rev C, 04/2007) (pdf, 808 kB) Data Sheets PDF
AN-911: A Detailed Guide to Powering the TigerSHARC Processors  (pdf, 239 kB) Application Notes PDF
ADP1823, ADP2106, ADP1821 Reference Design  (pdf, 189 kB)
Six Output Voltages: 1.2 V, 1.8 V, 2.5 V, 3.3 V, 5 V, 12 V; Output Current: 1 A to 4.5 A; Input voltage: 14.4-20.0 V; Ripple 2% ppk of Output Voltage; Transient step ±5%, 50% max load
Power Reference Designs PDF
ADP1821 Reference Design  (pdf, 1251 kB)
Two Output Voltages: 1.5 V, 1.2 V; Output Current: each 20 A; Input voltage: 12 V; DC plus Ripple <±2% of Output Voltage; Transient step ±5%, 50% max load
Power Reference Designs PDF
ADP1829 & ADP1821 Reference Design  (pdf, 309 kB)
Five Output Voltages: 1.2 V, 1.8 V, 3.3 V, 5 V, 12 V; Output Current: 1 A to 4.5 A; Input voltage: 15.2-16.8 V; Ripple 50 mV ppk; Transient step ±5%, 50% max load
Power Reference Designs PDF
ADP1821 Reference Design  (pdf, 0)
Single Output Voltage: 5.0 V; Output Current: 1.4 A; Input voltage: 9 V to 20 V; Ripple <1% ppk of Output Voltage; Transient step ±5%, 50% max load
Power Reference Designs PDF
ADP1821 Reference Design  (pdf, 103 kB)
One Output Voltage: 5 V; Output Current: 4 A; Input voltage: 12.0-44.0 V; Ripple 2% ppk of Output Voltage; Transient step ±5%, 50% max load
Power Reference Designs PDF
DC-to-DC Switching Regulator IC Solutions (10/06)  (pdf, 3205 kB) Overview PDF
RAQs index Rarely Asked Questions HTML
Glossary of EE Terms Glossary HTML

Design Tools,Models,Drivers & Software

Title Content Type File Type
ADP182x Buck Designer Tool  (zip, 0)
Microsoft Excel download tool from ADIsimPower to generate a power supply design complete with a schematic, bill of materials, and performance specifications.
ADIsim Design/Simulation Tools ZIP
Download files for ADIsimPower™ Voltage Regulator Design Tool
The individual Excel-based voltage regulator design tools used in ADIsimPower™.
ADIsim Design/Simulation Tools HTML
Launch of ADIsimPower Voltage Regulator Selection Vin (min) V Vout V   Find Solutions
Vin (max) V Iout A

Evaluation Kits & Symbols & Footprints

Evaluation Boards & KitsView the Evaluation Boards and Kits page for documentation and purchasing

Symbols and Footprints— Analog Devices offers Symbols & Footprints which are compatible with a large set of today’s CAD systems for broader and easier support.

SampleSample & Buy

Price, packaging, availability

Price Table Help

The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.

ADP1821 Evaluation Board for 20 A Step-Down
Model Description Price RoHS View PCN/ PDN Check Inventory/
Purchase/Sample
ADP1821-EVALZ Status: Production Evaluation Board $60.72 Yes -

Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.

Check Inventory & Purchase

View Sales and Distribution Offices

沪ICP备09046653号
content here.
content here.

Review this Product

Close