The KTU1121A provides four conducting paths with overvoltage protection (OVP) for Type-C’s CC, SBU signals. Once an overvoltage event is detected, it will shut down all paths to protect circuits in system side, like PD controller from damage.

All the SBU and CC switches have very low oncapacitance for broad bandwidth to allow high-speed signal passing through without loss. The CC1/2 switches have low on-resistance for passing VCONN power up to 1.25A.

During dead battery conditions, internal 5.1kΩ resistors automatically pull-down on CC1/2 to ensure that the upstream source provides 5V on VBUS.

The KTU1121A is packaged in RoHS and Green compliant 16-bump WLCSP 1.7mm x 1.7mm package or 20 pin 3mm x 3mm TQFN package.


  • Thunderbolt™ compatible
  • Overvoltage Protection
    • 24VDC Tolerance on CC 1/2, SBU 1/2
    • CC 1/2 OVP = 5.8V
    • SBU 1/2 OVP = 4.8V
    • Fast 70ns Response Time
  • IEC61000-4-5 Surge Protection
    • ±40V Surge Tolerance on CC 1/2
    • ±30V Surge Tolerance on SBU 1/2
  • IEC61000-4-2 ESD Protection
    • ±15kV air gap on CC 1/2, SBU 1/2
    • ±8kV contact on CC 1/2, SBU 1/2
    • ±2kV HBM on all pins (JEDEC JS-001-2017)
  • CC Switches:
    • 1.25A, 270mΩ, 40pF, 140MHz
    • Automatic 5.1kΩ dead battery pull-down
  • SBU Switches:
    • 3Ω, 11pF, 800MHz
  • 2.5V to 5.5V Operating Supply Voltage Range
  • -40°C to 85°C Operating Temperature Range
  • 16-bump WLCSP 1.7mm x 1.7mm (0.4mm pitch)
  • 20 pin TQFN 3mm x 3mm (0.4mm pitch)
  • RoHS and Green Compliant


  • Notebooks, PCs, Netbooks, Tablets, Monitors, TVs
  • Gaming Devices, Set-top Boxes, Networking

Packaging Information

Package Dimensions Bumps Package Code
WLCSP44-16 1.700mm x 1.700mm x 0.620mm 16 GAB
TQFN33-20 3.00mm x 3.00mm x 0.75mm 16 UAJ


Vin (min)  Vin (max)  IQ (µA) ON Resistance (mΩ) Switch Con (pF) Surge Rating (V) OVP Turn Off Response Time (ns) Package Package Alt.
2.5V 5.5V 40 270 11/40 CCx = ±40
SBUx = ±30
70 WLCSP44-16
1.70 x 1.70

Technical Documentation

Description Documents Type
Package Outline DrawingTQFN33-20 UAJ PODPDF

Evaluation Tools

Documents Type
User ManualPDF
Quick Start GuidePDF
Bill of MaterialsXLSX
3D BoardPDF


Part Number Marking Operating Temperature Package
KTU1121AEUAJ-TD RPYWZ2 -40°C to +85°C TQFN33-20
Purchase Options
Buy from Digi-Key
Buy from Mouser