40V Quad Channel Digital PWM/PFM Programmable Power Management System
Data Sheets OBS (Obsolete)


Information 40V Quad Channel Digital PWM/PFM Programmable Power Management System
# of Outputs 4
VIN MAX (V) 40
VOUT MIN (V) 0.6
VOUT MAX (V) 0.9*Vin
Set Point Resolution (mV) 2.5
Controller/ Regulator Controller
Gate Drive Pull Up/Down 4ohm / 2ohm
Internal MOSFETs No
IQ (mA) 4
Programmable Frequency Range (MHz) 0.1 to 1.2
Control Technology 17 bit DPWM/DPFM
NVM Technology Flash
Junction Temp Range (°C) -40 to 125
Package TQFN44
Special Features External 5V bias support, Exapanded GPIO Options
PowerArchitect Version# 5
Additional Features
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The XR77129 is a quad channel Digital Pulse Width Modulated (DPWM) step-down (buck) controller. An extremely wide 6V to 40V input voltage range allows for single supply operation from standard power rails.

With integrated FET gate drivers, two LDOs for standby power and a 105kHz to 1.23MHz independent channel to channel programmable constant operating frequency, the XR77129 reduces overall component count and solution footprint and optimizes conversion efficiencies. A selectable Digital Pulse Frequency Mode (DPFM) capable of better than 80% efficiency at light current load and low operating current allow for portable and Energy Star compliant applications. Each XR77129 output channel is individually programmable as low as 0.6V with a resolution as fine as 2.5mV, and configurable for precise soft-start and soft-stop sequencing, including delay and ramp control.

The XR77129 operation is fully controlled via a SMBus-compliant I2C interface allowing for advanced local and/or remote reconfiguration, full performance monitoring and reporting as well as fault handling.

Built-in independent output overvoltage, over temperature, overcurrent and undervoltage lockout protections insure safe operation under abnormal operating conditions.

The XR77129 is offered in a RoHS compliant, "green"/halogen free 44-pin TQFN package.

  • Quad channel step-down controller
    • Digital PWM 105kHz to 1.23MHz operation
    • Individual channel frequency selection
    • Patented digital PFM with ultrasonic mode
    • Patented over sampling feedback
  • Pin compatible to XRP7724 with added features
    • Additional GPIO configurability
    • Current limit fault options
    • Additional conditional fault options
    • Improved output voltage accuracy
  • 6V to 40V input voltage
  • 0.6V to 5.5V native output voltage
  • SMBus compliant - I<sup>2</sup>C interface
    • Full monitoring and reporting
  • 3 x 15V capable PSIO + 2 x GPIOs
  • Full start/stop sequencing support
  • Built-in thermal, overcurrent, UVLO and Output overvoltage protections
  • On board 5V and 3.3V standby LDOs
  • On board non-volatile memory
  • Evaluation Board, Demo Kit and Configuration Module (XCM) are available for evaluation and development purposes only
  • Supported by PowerArchitect™ Design and Configuration Software updated to support output voltage dividers for higher output voltages
  • Third-Party Programming Support

  • Automotive infotainment
  • Industrial control systems
  • Audio systems
  • Automatic test equipment
  • Video surveillance systems

Documentation & Design Tools

Type Title Version Date File Size
Data Sheets XR77129 40V Quad Output Digital PWM/PFM Universal PMIC 1C January 2021 4.8 MB
Application Notes AN200, Downloading and Installing CAD Symbols and Footprints with Ultra Librarian April 2019 1.2 MB
User Guides & Manuals XRP77xxEVB-XCM-V62 (Configuration Module) 1.0.1 October 2017 880.5 KB
User Guides & Manuals XR77129 Evaluation Board Manual 1.0.0 December 2014 1.8 MB
Product Flyers Universal PMICs April 2019 2 MB
Product Brochures Power Management Brochure October 2020 2.4 MB
Symbols & Footprints XR77129ELB-F CAD File (.bxl) September 2018 209.1 KB
PowerArchitect PowerArchitect
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Quality & RoHS

Part Number RoHS | Exempt RoHS Halogen Free REACH TSCA MSL Rating / Peak Reflow Package
XR77129ELB-F N Y Y Y Y L3 / 260ᵒC TQFN44 7x7

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
XR77129ELB-F TQFN44 7x7 -40 125 OBS XRP7714ILBTR-F together with XR76205ELTR-F
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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 PDF
TQFN44 7x7
  • JEDEC Reference: MO-220
  • MSL Pb-Free: L3 @ 260ºC
  • MSL SnPb Eutectic: n/a
  • ThetaJA: 30.2ºC/W
  • Bulk Pack Style: Tray
  • Quantity per Bulk Pack: 260
  • Quantity per Reel: 3000
  • Quantity per Tube: n/a
  • Quantity per Tray: 260
  • Reel Size (Dia. x Width x Pitch): 330 x 16 x 12
  • Tape & Reel Unit Orientation: Quadrant 1
  • Dimensions: mm
  • Length: 7.00
  • Width: 7.00
  • Thickness: 0.8
  • Lead Pitch: 0.50


Distribution Date Description File
03/05/2021 Product Discontinuation Notice
07/04/2018 Product Discontinuation Notice
07/21/2017 Qualification of alternate assembly subcon, ANST.
07/11/2017 Product Discontinuation Notification

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The -F suffix indicates ROHS / Green compliance: