20A Integrated Power Stage "DrMOS" with Current and Temperature Monitoring
Data Sheets OBS (Obsolete)


Information 20A Integrated Power Stage "DrMOS" with Current and Temperature Monitoring
# of Outputs 1
IOUT/Ch (A) 20
VIN MIN (V) 4.5
VIN MAX (V) 17
VOUT MAX (V) 3.3
Switching Frequency (kHz) 1500
Efficiency (%) 84
X-Y Dimension (mm) 4x5
Package QFN
Junction Temp Range (°C) -40 to 125
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The XR78021 is an integrated power stage containing a synchronous buck gate driver which is packaged with both half bridge MOSFETs designed to provide output currents up to 20Amps. Also known as “DrMOS” (Driver plus MOSFETs), the package design provides very low thermal impedance and excellent EMI performance by minimizing parasitic inductances. The ratio of the MOSFET RDS(ON) is optimized for conversions from 12V rails to the low output voltages required for the latest processor and chipsets of computing systems.
Computing systems are demanding more and more telemetry of the power system. The XR78021 monitors internal temperature (TOUT pin) and uses that temperature information to provide a temperature corrected current output (IOUT pin) derived from the inductor DCR. The output current information has minimal phase delay and is suitable for use with current mode PWM and valley current mode constant on-time control.
TOUT serves the secondary function of a fault flag for VCC UVLO and Over-Temp fault. The XR78021 is offered in a 4x5x0.9mm QFN package.

  • 20A Integrated Power Stage
  • Input Voltage Range: 4.5V to 17V
  • Output Voltage Range: 0.6V to 3.3V
    • 0.6V to 5.5V without current sense
  • IMON output 5mV/A (DCR=0.29mohm) with temperature compensation
    • Suitable for current mode control loops
  • TOUT output 8mV/°C with fault flags for VCC UVLO and temperature
  • Designed for 3.3V tristate PWM outputs
  • Boost pin refresh
  • 4x5x0.9mm Lead free RoHS compliant package

  • Servers
  • Networking Equipment
  • Industrial PC

Documentation & Design Tools

Type Title Version Date File Size
Data Sheets XR78021 20A Integrated Power Stage “DrMOS” with Current and Temperature Monitoring July 2019 1.5 MB
Product Briefs XR78021 Product Brief October 2017 209.8 KB
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Quality & RoHS

Part Number RoHS | Exempt RoHS Halogen Free REACH TSCA MSL Rating / Peak Reflow Package
XR78021ELTR-F Y | 7a N Y Y Y QFN27 5x4 L2 / 260ᵒC

Click on the links above to download the Certificate of Non-Use of Hazardous Substances.

Additional Quality Documentation may be available, please Contact Support.

Parts & Purchasing

Part Number Pkg Code Min Temp Max Temp Status Suggested Replacement PDN
XR78021ELTR-F QFN27 5x4 -40 125 OBS
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Part Status Legend
Active - the part is released for sale, standard product.
EOL (End of Life) - the part is no longer being manufactured, there may or may not be inventory still in stock.
CF (Contact Factory) - the part is still active but customers should check with the factory for availability. Longer lead-times may apply.
PRE (Pre-introduction) - the part has not been introduced or the part number is an early version available for sample only.
OBS (Obsolete) - the part is no longer being manufactured and may not be ordered.
NRND (Not Recommended for New Designs) - the part is not recommended for new designs.


Pkg Code Details Quantities Dimensions
QFN27 5x4
  • JEDEC Reference: MO-220
  • MSL Pb-Free: L2 @ 260ᵒC
  • MSL SnPb Eutectic:
  • ThetaJA: 52.48ᵒC/W
  • Bulk Pack Style: Tray
  • Quantity per Bulk Pack: 490
  • Quantity per Reel: 3000
  • Quantity per Tube: N/A
  • Quantity per Tray: 490
  • Reel Size (Dia. x Width x Pitch): 330 x 12
  • Tape & Reel Unit Orientation: Pin 1 at quadrant 1
  • Dimensions: mm
  • Length: 5
  • Width: 4
  • Thickness: 1
  • Lead Pitch: 0.5


Distribution Date Description File
10/28/2022 Product Discontinuation Notice
12/12/2018 Product Discontinuation Notice

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