Synchronous rectifier controller With Ultra-Low Standby current


Product details


Frequency (Max) (kHz) 130 UVLO thresholds on/off (V) 4/3.6 Features USB Type-C Compatible Operating temperature range (C) -40 to 125 open-in-new Find other Synchronous rectifier (SR) controllers

Package | Pins | Size

SOT-23 (DBV) 6 5 mm² 2.9 x 1.6 open-in-new Find other Synchronous rectifier (SR) controllers


  • Secondary-Side SR Controller Optimized for
    5-V to 24-V Output Discontinuous/Transition Mode
    Only Flyback Converters
  • Volt-Second Balance Control Enables Highest
    Rectifier Efficiency
  • Compatible with PSR and SSR Flyback
  • Ultra Low 110-µA Standby Current Consumption
  • Auto-Detect Standby Mode Disables SR Switching
    for Lower No-Load
    Power Consumption
  • SR Turn-Off Independent of RDSON and Parasitic
  • Operating Frequency Up to 130 kHz
  • Wide VDD Range from 3.6 V to 28 V
  • Adaptive Gate Drive Clamp
  • Open and Short Pin Fault Protection
open-in-new Find other Synchronous rectifier (SR) controllers


The UCC24636 SR is a compact, 6-pin secondary-side synchronous rectifier MOSFET controller and driver for high efficiency Flyback converters operating in Discontinuous (DCM) and Transition mode (TM). Unlike traditional SR controllers which measure the SR MOSFET drain voltage, UCC24636 implements a volt-second balance control method to determine the turn off transition of the SR MOSFET; hence, SR conduction time is independent of the MOSFET RDSON, parasitic inductance or ringing allowing flexibility to designers in component slelction and PCB layout. This control method enables maximum SR conduction time and highest rectifier efficiency for a given MOSFET.

The controller has built in intelligence to detect converter no load operation and automatically enters standby mode. While in standby mode, it disables the SR MOSFET and lowers its bias supply current to 110µA to further reduce overall system standby power consumption. The wide VDD operating range for the controller allows direct bias from the converter output for fixed or variable output voltage designs. This eliminates the need for an auxilliary winding on the main transformer, which simplifies the circuit design and reduces the cost.

open-in-new Find other Synchronous rectifier (SR) controllers

Technical documentation

star = Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 7
Type Title Date
* Datasheet UCC24636 Synchronous Rectifier (SR) Controller With Ultra-Low Standby Current datasheet (Rev. A) Mar. 11, 2016
Application note UCC24630 and UCC24636 SR-Control Configurations Guide Dec. 18, 2017
Application note Design UCC28704 With UCC24636 (PSR+SR) Jan. 12, 2017
Technical article Biasing an SR controller IC in USB smartphone charging applications Dec. 08, 2016
Technical article USB chargers then and now: Type-C meets energy efficiency standards Sep. 23, 2016
Application note Agency requirements for stand-by power consumption w/ offline and PoL converters Jan. 26, 2016
User guide Using the UCC24636EVM Jan. 08, 2016

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Hardware development

document-generic User guide
The UCC24636EVM is a demonstration daughter board that allows quick installation into an existing DCM Flyback power supply to convert an output diode rectifier into a synchronous rectifier to improve efficiency. The board is programmed by the user and may be wired directly into the output stage (...)
  • Board includes UCC24636 and SR MOSFET
  • Retrofit in 5V or 12V DCM Flyback converter designs
  • SR MOSFET CSD19531 100V/5.3mΩ
  • User-programmable for 5-V to 12-V outputs

Design tools & simulation

SLUC604A.ZIP (55 KB)

Reference designs

Many TI reference designs include the UCC24636 Use our reference design selection tool to review and identify designs that best match your application and parameters.

CAD/CAE symbols

Package Pins Download
SOT-23 (DBV) 6 View options

Ordering & quality

Information included:
  • RoHS
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring

Recommended products may have parameters, evaluation modules or reference designs related to this TI product.

Support & training

TI E2E™ forums with technical support from TI engineers

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​​​​​​​