19V, 2A, 40µA IQ, High-Efficiency, Constant-On-Time, Step-Down Converter in a QFN (2mmx3mm) Package

Learn about our Evaluation Kit
Talk to an Engineer or get a Quote

Product Description

The MP2321 is a fully-integrated, high-efficiency, synchronous, step-down, switch-mode converter with 40μA of quiescent current. The MP2321 achieves 2A of continuous output current over a wide input supply range with excellent load and line regulation and can operate with high efficiency over a wide output current load range. The MP2321 is optimized for battery-operated applications and applications requiring high light-load efficiency. 
With constant-on-time (COT) control, the MP2321 provides very fast transient response, easy loop design, and very tight output regulation.
Full protection features include short-circuit protection (SCP), over-current protection (OCP), under-voltage protection (UVP), and thermal shutdown.
The MP2321 requires a minimal number of readily available, standard, external components and is available in a space-saving QFN-14 (2mmx3mm) package.


Product Features

  • 4V to 19V Operating Input Range
  • 2A Output Current
  • 40μA Quiescent Current
  • Output Adjustable from 0.6V
  • 110mΩ/40mΩ High-Side/Low-Side RDS(ON) for Internal Power MOSFETs
  • Power Good Indicator
  • Programmable Soft-Start Time
  • Forced PWM or Auto PFM/PWM Mode Selectable
  • Programmable Switching Frequency
  • Thermal Shutdown
  • Short-Circuit Protection: Hiccup Mode
  • Available in a QFN-14 (2mmx3mm) Package


  • fsw (max) (kHz)0
  • Vin (min) (V)4
  • Vin (max) (V)19
  • Iout (max) (A)2
  • Isw Limit (typ) (A)4
  • Max Duty Cycle (%)1
  • Vfb (V)0.6
  • Iq (typ) (mA)0.04
  • Regulated Outputs1
  • Vout (min) (V)0.6
  • GradeCatalog
  • PackageQFN-14 (2x3)
  • Control ModeCOT
  • Common FeaturesExternal Soft Start, Light-Load Efficiency, Power Good, Synchronous Rectification
  • Special FeaturesProgrammable Frequency

2A, 19V, Constant-On-Time Step-Down Switcher Evaluation Board

The EV2321-D-00A is used for demonstrating the performance of MP2321, a fully-integrated, high efficiency, synchronous step-down switch mode converter with the feathered 40uA quiescent current. MP2321 provides up to 2A continuous output current over a wide input supply range with constant-on-time control for fast loop response.

High power efficiency over a wide load range is achieved by scaling down the switching frequency at light load to reduce the switching related loss by constant on time control. Short circuit and thermal shutdown provides reliable, fault-tolerant operation.

MP2321 is available in 2mmx3mm 14-pin QFN package.

$25.00 + tax

Quality Policy, Certificates & Reliability Reports
All MPS parts are lead-free, halogen-free and adhere to the RoHS directive. See Environmental section for details.