Add to Signal Chain Designer

ADP1621:  Constant-Frequency, Current-Mode Step-Up DC/DC Controller

Product Details


The ADP1621 is a fixed-frequency, pulse-width modulation (PWM), current-mode, step-up converter controller. It drives an external n-channel MOSFET to convert the input voltage to a higher output voltage. The ADP1621 can also be used to drive flyback, SEPIC, and forward converter topologies, either isolated or nonisolated.

The ADP1621 eliminates the use of a current-sense power resistor by measuring the voltage drop across the on resistance of the n-channel MOSFET. This technique, allowed up to a maximum voltage of 30 V at the switch node, maximizes efficiency and reduces cost. For switch-node voltages higher than 30 V or for more accurate current limiting, the CS pin can be connected to a current-sense resistor in the source of the MOSFET. The slope compensation is implemented by an external resistor, allowing a wide range of external components (inductors and MOSFETs), and can be chosen for various switching frequencies and input and output voltages.

The ADP1621 supply input voltage range is 2.9 V to 5.5 V, although higher input voltages are possible with the use of a small-signal NPN pass transistor or a single resistor. The voltage of the power input can be as low as 1 V for fuel cell applications. The switching frequency is set by an external resistor over a range of 100 kHz to 1.5 MHz and can be synchronized to an external clock by using the SDSN pin. The shutdown quiescent current is less than 10 μA. The ADP1621 has a thermal shutdown feature that shuts down the gate driver when the junction temperature reaches approximately 150°C. The internal soft start circuit limits inrush current at startup. The ADP1621 is available in the 10-lead MSOP lead-free package and is specified over the −40°C to +125°C junction temperature range.

Applications

  • APD bias
  • Portable electronic equipment
  • Isolated dc/dc converter
  • Step-up/step-down dc/dc converter
  • LED driver for laptop computer and navigation system
  • LCD backlighting

FEATURES and BENEFITS

  • 92% efficiency (no sense resistor required)
  • ±1.0% initial accuracy
  • IC supply voltage range: 2.9 V to 5.5 V
  • Power-input voltage as low as 1.0 V
  • Capable of high supply input voltage (>5.5 V) with an external NPN or a resistor
  • VIN UVLO and 35 mA shunt regulator
  • External slope compensation with 1 resistor
  • Programmable operating frequency (100 kHz to 1.5 MHz) with 1 resistor
  • Lossless current sensing for switch-node voltage <30 V
  • Resistor current sensing for switch-node voltage >30 V
  • Synchronizable to external clock
  • Current-mode operation for excellent line and load transient responses

Functional Block Diagram for ADP1621

Documentation

Title Content Type File Type
ADP1621: Constant-Frequency, Current-Mode Step-Up DC/DC Controller Data Sheet (Rev B, 06/2012) (pdf, 813 kB) Data Sheets PDF
AN-1126: More Boost with Less Stress: the SEPIC Multiplied Boost Converter  (pdf, 330 kB) Application Notes PDF
Introduction to ADIsimPower
ADIsimPower is a smart selector and a collection of downloadable tools that produce complete and optimized power designs. Schematic, bill of materials, and performance data are customized to your specific needs in minutes.
Videos HTML
ADP1621 ±15V Dual-Output SEPIC-Cuk  (pdf, 1239 kB) Power Reference Designs PDF
ADP1621 28V Boost  (pdf, 168 kB)
Iout of at least 0.5 amps (will do more). Simulation results showing stability and transient response.
Power Reference Designs PDF
PRD1205: Quasi-Isolated Flyback  (pdf, 0)
This is a 10V - 14 input isolated flyback converter which uses the ADP1621 controller and an AD8691 operational amplifier. The target application of this converter is for powering a portable media player from the accessory power outlet of an automobile.
Power Reference Designs PDF
RAQs index Rarely Asked Questions HTML
Glossary of EE Terms Glossary HTML

Design Tools,Models,Drivers & Software

Title Content Type File Type
ADP1621 Coupled-SEPIC Design 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
ADP1621 Cuk Design 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
ADP1621 Boost Regulator Design 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.

ADP1621 Evaluation Board
Model Description Price RoHS View PCN/ PDN Check Inventory/
Purchase/Sample
ADP1621-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