SRK2000A:Synchronous rectifier smart driver for LLC resonant converters

The SRK2000A smart driver implements a control scheme specific to secondary side synchronous rectification in LLC resonant converters that use a transformer with center tap secondary winding for full wave rectification.

It provides two high current gate drive outputs, each capable of driving one or more N-channel Power MOSFETs. Each gate driver is controlled separately and an interlocking logic circuit prevents the two synchronous rectifier MOSFETs from conducting simultaneously.

The control scheme in this IC allows for each synchronous rectifier to be switched on as the corresponding half-winding starts conducting and switched off as its current goes to zero. The SRK2000A device implements matched turn-off MOSFET thresholds. A unique feature of this IC is its intelligent automatic sleep mode. It allows the detection of a low-power operating condition for the converter and puts the IC into a low consumption sleep mode where gate driving is stopped and quiescent consumption is reduced. In this way, converter efficiency improves at light load, where synchronous rectification is no longer beneficial. The IC automatically exits sleep mode and restarts switching as it recognizes that the load for the converter has increased.

A noticeable feature is the very low external component count required.

Key Features

  • Secondary side synchronous rectifier controller optimized for LLC resonant converters
  • Protection against current reversal
  • Safe management of load transient, light load and startup condition
  • Matched turn-off thresholds
  • Intelligent automatic sleep mode at light load
  • Dual gate driver for N-channel MOSFETs with 1 A source and 3.5 A sink drive current
  • Operating voltage range 4.5 to 32 V
  • Programmable UVLO with hysteresis
  • 250 μA quiescent consumption
  • Operating frequency up to 500 kHz
  • Available in SO-8 package
Product Specifications
DescriptionVersionSize
DS9993: Synchronous rectifier smart driver for LLC resonant converters2.0370 KB
Application Notes
DescriptionVersionSize
AN4027: 12 V - 150 W resonant converter with synchronous rectification using the L6563H, L6699 and SRK2000A3.02 MB
Presentations
DescriptionVersionSize
Secondary regulation Synchronous rectification controllers2 MB
Brochures
DescriptionVersionSize
Brochure Power management guide05.20164 MB
Solution Evaluation Tools
Part NumberManufacturerDescription
EVL400W-ADP/ATX12V - 400W SMPS for Adapter, Desktop and AIO using L4984D, L6699 and SRK2000A
Sample & Buy
Part NumberPackagePacking TypeUnit Price (US$) *QuantityECCN (EU)ECCN (US)Country of Origin
SRK2000ASO-8Tube0.731000NECEAR99MOROCCO
SRK2000ATRSO-8Tape And Reel0.731000NECEAR99MOROCCO
Quality & Reliability
Part NumberPackageGradeRoHS Compliance GradeMaterial Declaration**
SRK2000ASO-8IndustrialEcopack2md_o7-wspc-so-wspc-08-wspc-.15-wspc-jedec_cbo7-wspc-u1b6ab5.pdf
md_o7-wspc-so-wspc-08-wspc-.xml
SRK2000ATRSO-8IndustrialEcopack2md_o7-wspc-so-wspc-08-wspc-.15-wspc-jedec_cbo7-wspc-u1b6ab5.pdf
md_o7-wspc-so-wspc-08-wspc-.xml
Synchronous rectifier smart driver for LLC resonant converters SRK2000A
12 V - 150 W resonant converter with synchronous rectification using the L6563H, L6699 and SRK2000A L6699
Secondary-side rectification for an LLC resonant converter featuring the SRK2000 SRK2000
Very low drop voltage regulators with inhibit KFXX
md_o7-wspc-so-wspc-08-wspc-.15-wspc-jedec_cbo7-wspc-u1b6ab5.pdf SRK2000A
md_o7-wspc-so-wspc-08-wspc-.xml TS4871